Dams Safety Committee Annual Report 2018 / 2019 · NSW Dams Safety Committee Annual Report 2016 /...

ANNUAL REPORT

Dams Safety Committee

Annual Report

2018 / 2019

ANNUAL REPORT

NSW DAMS SAFETY COMMITTEE FLOOR 11, MACQUARIE TOWER, 10 VALENTINE AVENUE,

PARRAMATTA NSW 2150 (LOCKED BAG 5123, PARRAMATTA NSW 2124)

OFFICE PHONE: (02) 9842 8073 EXECUTIVE ENGINEER: (02) 9842 8070

Website: http://www.damsafety.nsw.gov.au

Email: [email protected]

BUSINESS AND SERVICE HOURS ARE NORMALLY 9.30 am to 4.00 pm MONDAY to FRIDAY

Please note that the NSW Dams Safety Committee (DSC) only has a small number of technical staff who are often away from the office on inspections. Accordingly, technical questions may not be able to be answered immediately, although every effort will be made to pass on messages to ensure a prompt response.

Cover Picture: Lake Parramatta Dam, a 15m high masonry arch dam, situated just to the north of Parramatta was originally built for water supply but now provides public recreational use and some flood mitigation to Parramatta. It is Australia’s oldest dam, being built in 1855, but it still meets modern dam safety standards and is managed to those standards. NOTE: In accordance with Premier & Cabinet’s Memorandum M2013-09, the Committee has only printed in-house a

limited number of hard copies (in black and white). Report distribution will be substantially electronic.

ISSN 0816-2727

Index

AActivities, nature and range ................................................... 9 Address .................................................................................. 1 Assets ............................................................................. 10, 54

BBusiness and Service Hours ................................................... 1

CCode of conduct ................................................................... 50 Committee, purpose, origin ................................................... 9 Contacting the Committee ..................................................... 1

DDams, prescribed, statistics .................................................. 67

EEmergencies ................................................................... 10, 38 Equal Employment Opportunity (EEO) .............................. 50 Ethnic Affairs ....................................................................... 50

GGovernment Information Public Access .............................. 50 Guidance Sheets ................................................................... 23

IIndependent Auditor's Report .............................................. 52

LLegislation ............................................................................. 8

MManagement Improvement Plans and Achievements ...... 3, 17 Meetings, attendance at ........................................................ 11 Members, appointment of members, name, position, qualifications ........................................................................ 12 Mining .................................................................................. 16

OObjectives .............................................................................. 3 Organisational Chart ............................................................ 10

PPerformance Measures ......................................................... 17

SStaff, name, position, qualifications .................................... 14 Sub-committees ................................................................... 11

TTelephone of Office ............................................................... 1

ANNUAL REPORT 1

ABN 55 079 703 705 The Hon Melinda Pavey, MP Minister for Water Property & Housing Locked Bag 5123 52 Martin Place PARRAMATTA NSW 2124 SYDNEY NSW 2000 Phone: (02) 9842 8073 Fax: (02) 9843 8071 Our Ref: 10.102.007 Dear Minister Pavey,

We have pleasure in submitting to you, for presentation to Parliament, the NSW Dams Safety Committee's Annual Report for the year ended 30 June 2019. This Annual Report has been prepared in accordance with the Annual Reports (Statutory Bodies) Act 1984 and the Annual Reports (Statutory Bodies) Regulation 2015.

Yours sincerely,

Sam Banzi Chair

Jeffrey Gleeson Deputy Chair

NSW Dams Safety Committee Annual Report 2018 / 2019

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CONTENTS

Index ............................................. Inside Front Cover

Index ........................................................................... 1

CONTENTS ................................................................. 2

Overview by Chair ..................................................... 3Our Objectives ............................................................. 3Targets ......................................................................... 3Highlights ..................................................................... 3Our People ................................................................... 4Our Stakeholders ......................................................... 5The Future ................................................................... 5

1. Charter ................................................................ 71.1. Why do we have a Dams Safety Committee

(DSC) in NSW? ................................................... 71.2. What Legislation defines our Functions? ............ 71.3. What are the Functions of the DSC? ................... 7

2. Access and Contact ........................................... 8

3. Aims, Objectives and Values ............................ 83.1. Mission and Objectives ....................................... 83.2. Our Values .......................................................... 8

4. Management and Structure ............................... 94.1. DSC Structure and Organisation Chart ............... 94.2. Sub-committees ................................................ 114.3. Meetings ............................................................ 114.4. Committee Members ......................................... 124.5. Committee Staff ................................................. 13

5. Summary Review of Operations ..................... 155.1. Major Achievements for 2018/19 ....................... 155.2. Budget Highlights .............................................. 15

5.3. Performance Indicators ..................................... 15

6. The Future ........................................................ 186.1. Dams Safety Management ................................ 186.2. Mining Management near Dams ....................... 206.3. Administration and Information Systems ........... 206.4. NSW Dams Safety Review ............................... 20

7. Review of Operations ...................................... 217.1. Dams Safety Management ................................ 217.2. Regulation of Mining near Dams ....................... 367.3. Information Systems ......................................... 39

8. Stakeholders .................................................... 408.1. Liaison with Stakeholders ................................. 418.2. Education and Training of Members and Staff

and Associated Matters ..................................... 43

9. Administration and Human Resources ......... 44

10. Finance ............................................................. 4510.1.Independent Auditor’s Report ........................... 4510.2Audited Financial Statements ........................... 4810.3 Internal Audit and Risk Management

Attestation for the 2018/19 Financial Year ........ 64

Appendix A – Dam Owner and Consequence Category Summary - 30 June 2019 ................ 65

Appendix B – Current Prescribed Dams in NSW – 30 June 2019 .................................................... 66

Map - NSW Dams Safety Committee - Prescribed Dams in NSW as at July 2019 ............. last page

LIST OF TABLES Table 5.1 – 2018/19 Budget Highlights .............. 15

Table 5.2 - DSC Performance Indicators ........... 16

Table 7.1 - Interation of DSC over Dam Life Cycle ............................................... 23

Table 7.2 – Amendments to DSC Information ... 21

Table 7.3 - Guidance Sheets for Dams Safety .............................................. 22

Table 7.4 - Dams Modified for Safety Upgrading since 2001 (not including tailings dams) .................. 27

Table 7.5 - Status of Upgrading Activities for Dams and Basins under DSC Particular Review ............................ 31

Table 7.6 - Status of Activities on Dams issued with S18 Show Cause Notices ............................................ 30

Table 7.7 - Dams issued with S15 Notices outstanding at 30th June 2019 ......... 30

Table 7.8 – Guidance Sheets for Mining near Dams ............................................... 37

Table 7.9 - Mining in Notification Areas .............. 38

Table 7.10 - Monitored Approved Mining 2018/19 ........................................... 38


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Overview by Chair

Our Objectives The mission of the NSW Dams Safety Committee (DSC), an independent statutory body constituted under the Dams Safety Act 1978, is to ensure the safety of prescribed dams in NSW. Under its Act, the DSC has roles to: � Protect community safety and interests from dam failure by ensuring that prescribed dams risks are tolerable;

� Ensure that DSC safety requirements are met, that risks are properly managed, regularly reviewed, and reduced to a level as low as reasonably practicable; and

� Ensure the risks to dams and their stored waters from the effects of mining are properly managed and tolerable.

The DSC is also empowered with various enabling functions under the Mining Act 1992 in its role of regulating mining under stored waters to fulfil the above last-noted role.

To achieve its roles, the DSC follows a goals-based approach to dam safety regulation wherein the means of achieving compliance is not specified but instead goals are set that allow alternatives for achieving compliance. Dam safety responsibility lies principally with the dam owner, while the DSC has a challenge/audit role. The dams of interest to the DSC are the currently 410 prescribed dams whose failure would threaten lives or have significant community impacts.

Water and tailings dams have failed in a number of countries during the year. Some of these international dam incidents resulted in loss of life and all had damaging consequences. In January 2019 there was the catastrophic failure of a major tailings dam in Brazil, namely Brumadinho Tailings Dam, resulting in the deaths of over 300 people, causing significant environmental damage and resulting in the arrest of several of the owner’s personnel and consultants. In addition, in March 2018, at Cadia Mine near Orange, a large section of the embankment of its Northern Tailings Dam suddenly collapsed and, after a year of site investigations, the failure is now being attributed to a localised weakness undetected in the dam’s foundation. These, and other, serious incidents and their widespread media coverage have served to highlight the major risks posed by dams and the potential catastrophic consequences of their failure.

It is recognised internationally that well organised, and regulated, dam safety management programs are essential to maintain the requisite levels of safety of dams and that best practice regulatory systems involve risk based dam safety management. NSW and Australia in general have been in the international forefront of adopting not only risk based dam safety management practices but also associated risk based regulatory frameworks.

For over 4 decades the DSC has required that mine owners develop a comprehensive engineering understanding of the effects of mining on stored waters and dams through detailed monitoring, analysis and research. This combination of an extensive local knowledge base, in conjunction with greater sophistication in monitoring technology, has resulted in the DSC’s having improved confidence to support the continued safe extraction of coal from under NSW storages.

Targets

The DSC’s targets are presented in Section 5.3 and in the associated Table 5.2 of this report. The main focus is on the maintenance of the programs for Surveillance Reports, dam inspections and Dam Safety Emergency Plans (DSEPs). Another main focus is on dam owners having schedules agreed with the DSC for activities leading to necessary safety improvements on dams and to follow up issues in a timely manner. The criteria targets in the DSC’s most recent Strategic Plan were substantially met, whilst maintaining DSC expenditure within budget.

Highlights

WaterNSW is the owner of the greatest portfolio number of large dams in this State. During 2018/19 the DSC continued to liaise closely with WaterNSW as it finalised its detailed portfolio risk assessment of its metropolitan dams which has highlighted some dams that may require safety upgrading. WaterNSW also continued construction of the second stage of its upgrading of Keepit Dam involving the complex post-tensioning strengthening of the dam’s gated concrete spillway section. The DSC thanks WaterNSW for the cooperation it has given to the DSC in proceeding with its dams safety review and upgrading programs.

Snowy Hydro Limited (SHL) continued to keep the DSC updated on SHL’s current five year dam safety management program, presented to the DSC initially in late 2015, for its portfolio of large dams (the second greatest portfolio number of large dams in NSW), with emphasis on several safety reviews, risk assessments, an ensuing PRA and associated investigations.

NSW Dams Safety Committee Annual Report 2016 / 2017 / 2019

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There are currently around 150 prescribed dams and basins owned by local government councils and other local water utilities (LWUs). Work continued during the year on a prioritised program to improve the safety of various LWU dams. Some of this programmed development is currently done through the auspices and assistance of DPI Water. The buttressing and flood security upgrading works at Tenterfield dam was completed in mid-2018 and the dam removed from the highest risk status group of dams. Detailed design studies are underway on Dumaresq Dam and construction of upgrading works at Winburndale Dam is programmed for completion by mid-2020.

In June 2016 the NSW State Government announced a decision to build a pipeline from the Murray River to Broken Hill to guarantee the town’s water security. The Premier Mike Baird, Minister Niall Blair and others were involved in the announcements of this major project. The DSC has since endorsed Essential Water’s subsequent request to decommission Imperial Lake Dam, part of Broken Hill’s water supply, after completion of pipeline in early 2019. The DSC continues to be updated on these matters by Essential Energy personnel.

In August 2012, 27 prescribed dams and basins were under particular review by the DSC due to their being in the highest risk status group. During 2017/18, Tenterfield Dam, Suma Park Dam and Kensington Centennial Pond Dam were removed, and one structure (Cadia North Tailings Dam) was added, to the highest risk list. At 1st July 2019, the number of dams and basins in this highest risk status group had been significantly lowered to 17 (see Table 7.5). Furthermore, it is likely that another 3 of the dams & basins also will have been removed from the highest risk status group by the end of the financial year 2019/20. Through the extensive continuing DSC liaison with the dam owners and the co-operation and committed work of the owners, a significant number of other dams and basins in the highest risk status group have definite upgrade programs in place. Investigations are also in place or well-progressed for the remaining dams in this group.

Mining continued around and under stored waters at a high rate throughout the year. Further Notification Areas (NAs) around dams were established due to the additional numbers of mining applications made. It should be noted that there had been an approximate doubling in total annual coal tonnage extracted from the NAs over the past ten years.

During 2018/19 approximately 35 million tonnes of coal were extracted from near, and under, storages (water and waste storages) within the NAs. With coal production royalties to the state government proportional to extraction volume, this 2017/18 extraction volume was similar to the substantial volumes produced in the three previous financial years.

Our People

The DSC members and staff kept their knowledge up-to-date through various professional technical activities external to the DSC. Various DSC members and staff continue to be involved in Australian National Committee on Large Dams (ANCOLD) and International Commission on Large Dams (ICOLD) matters. Some DSC members (including the DSC Chair and the other Engineers Australia nominated DSC member) and the DSC Executive Engineer are involved in various ANCOLD Working Groups.

Several DSC members and the DSC Executive Engineer attended the 2018 annual ANCOLD Conference & Workshop on Dams in October 2018 in Melbourne, Victoria. These annual ANCOLD Conferences provide valuable forums for exchange of information and updating on dam safety issues as well as providing the annual opportunity for dam safety regulators nationwide to meet and review pertinent issues.

The DSC is concerned in ensuring it is maintaining best practice. To this end, as well as its full organisation membership of ANCOLD, the DSC is also a member of the USA’s Association of State Dam Safety Officials (ASDSO), the Canadian Dam Association (CDA) and the New Zealand Society on Large Dams (NZSOLD). All of the above mentioned points concerning ANCOLD, ICOLD and various overseas authorities have helped greatly to supply highly valuable information and networking on national and international dam safety practices.

The DSC invests in staff training as it is very reliant on its staff to provide the reviews of the many submitted reports on dams and also the mining applications and associated report submissions for the respective Sub-committees to endorse. Staff reviews of technical documentation have been carried out in an extremely competent and professional manner and this makes the Committee’s work considerably simpler.

Once again the Committee wishes to record its appreciation of the competence, loyalty and dedication of its staff in meeting the DSC’s heavy workload and providing substantial services with few people. During 2018/19 the dam surveillance statistics achieved were again very good overall. The Committee commends its Surveillance and support staff for the very large workload completed in the last 12 months, including all reviews and audits of submitted reports completed in a timely manner. The Committee also commends its Mining and support staff for the substantial workload completed, including applications processed and conditioned, in the last year.


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Our Stakeholders

The DSC values a good working relationship with dam owners, mining companies, and their consultants. The DSC can thus communicate its goals and requirements and, once they understand the DSC’s safety benchmarks, dam owners and mining companies come to recognise their responsibilities and develop an ongoing commitment to dam safety.

Close contact is maintained by the DSC with owners of prescribed dams through meetings held during the year to discuss specific dam requirements, general procedures, and to ensure owners are able to communicate their concerns to the DSC. For example, during 2018/19 the DSC inspected 37 dams and basins, and held on-site meetings with owners’ personnel. DSC mining staff also inspected mine sites and held on-site meetings with personnel from those mines.

The DSC believes there is very good value in training the operators of NSW prescribed dams in dam safety and surveillance matters. During 2018/19 the DSC was involved in organising and running four dam safety training courses. Three 4-day dam safety/surveillance courses for water dam operators and other dam staff was held at Port Macquarie in late 2018 and early 2019, and one 3-day program for tailings dam operators was held at Port Stephens in early 2019. These courses each attracted the fully subscribed 25-30 participants.

Since the inception of the standard training program a number of years ago, and enhancement since then with the creation of a TAFE certificate course, these training courses have resulted in a noticeable improvement in the general standard of dam owners’ dam safety management. This training course work is seen as an important part of the DSC’s education role for dam owners. Also, the increasing emphasis over a number of years by the DSC on owner education in NSW has been reflected in numerous requests from dam owners within and outside NSW for educational assistance in similar training courses for dam operators and this has continued throughout the year.

The DSC’s main requirements are outlined in its Guidance Sheets. All the DSC’s Guidance Sheets and also its standard forms are readily available for its stakeholders, through easy accessibility on the DSC’s website.

The Future

The DSC’s development and advocacy of a “Risk Management Policy Framework for Dam Safety” from 2000 onwards led to the NSW Government’s endorsement in 2006 of this risk management policy framework. This significant regulatory policy framework was then progressively implemented by the DSC, especially through substantial redevelopment of its Guidance Sheets. The risk regulatory framework allows prescribed dam owners to formally adopt risk assessment and management approaches. The DSC has effectively incorporated the main principles of its risk based regulatory policy into its Guidance Sheets. As one of the leaders of NSW regulators in implementing a risk based framework, the DSC considers it current approach accords well with the government’s general risk regulatory policies.

Improvements and expansions to the DSC’s databases continued during 2018/19 and also will do so into the future. Extensive DSC consultation with its stakeholders will continue. The DSC will continue to engage with other NSW safety, environmental and economic regulators to ensure that its Guidance Sheets fit in a consistent regulatory approach. The DSC will continue its information exchange program with other state dam safety regulators on their dams for which failure could adversely affect NSW communities, and on allied regulatory matters. The DSC’s Chair, another DSC member and the Executive Engineer attended the state dam safety regulators’ annual meeting that was held in conjunction with the ANCOLD Conference in Melbourne in October 2018. This annual meeting of the nation’s dam safety regulators is a very worthwhile forum in which NSW should continue to actively participate.

With the developed detailed safety benchmarks and guidance that are encompassed within the DSC policy framework, the DSC feels that New South Wales continues as one of the world leaders in dam safety management. Indeed, through the risk based regulatory approaches adopted by several Australian States (including NSW) and the influence of ANCOLD and its Guidelines in this important subject, Australia is recognised internationally as at the strategic forefront of this modern dam safety management approach of incorporating a risk based framework.

The risk imposed by NSW dams will continue to be steadily reduced. Dam safety management programs are well established for all prescribed structures and will be further improved. Dam Safety Emergency Plans (DSEPs) are in place for a large majority of them. The DSC will continue to work with owners to ensure that all dams requiring DSEPs have them and are regularly updated and periodically tested. As consequences of failure for some dams would be catastrophic, the likelihood of their failure needs to be very low.


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It is the dam owner’s responsibility to determine and implement measures to lower dam safety risks to a tolerable level. The owner’s choice of investigating and implementing structural and/or non-structural options for risk reduction is a significant part of the DSC’s well established and largely goals based regulatory requirements in which the dam owner is responsible for demonstrating compliance in achieving sufficient risk reduction. This existing policy also accords with the new Dams Safety Act 2015 (see below), with various statements reaffirming that dam owners should have flexibility to explore a broad array of options and strategies to deliver the required level of public safety.

A substantial passage of time has elapsed since the Dams Safety Act 1978 and the associated DSC were established. In 2013 the government embarked on a review of NSW dam’s safety in general and its regulatory process. That work culminated with the passage of the Dams Safety Bill 2015 through the NSW parliament during September 2015 and the ensuing Bill’s assent. Notably the Minister’s associated media releases about the Dams Safety Bill 2015 stated that it will remain business as usual for the DSC until the new Act is fully implemented and that dam owners must continue to comply with any requests from the DSC, under the Dams Safety Act 1978 until the new Act is fully implemented.

On behalf of the government, DPI Water initiated the implementation of the new Act with the formation of an interim advisory committee in October 2016. While the DSC continues with its work and role under the Dams Safety Act 1978, the interim advisory committee continues to work separately on developing the redefined dam safety standards and undertaking other regulatory and policy development in relation to dams safety. It is expected that the advisory body will continue to liaise and consult at various intervals with the DSC about the current dams safety standards and requirements and regulatory approach whilst working towards implementation of the new Act later in 2019.

The DSC looks forward to continuing in close partnership with the government during the next year in the necessary and extensive work required to fully implement the new Act. With an already extensively developed risk based regulatory approach to dam safety management, dam safety in NSW compares very favourably with the best dam safety programs world-wide. The DSC expects that the full implementation of the new Act will further develop and enhance the current risk based dams safety regulatory system. The DSC’s and NSW Government’s ultimate aim is that the risks from NSW dams to the community and the environment will be tolerably low for all prescribed dams. As myself and Deputy Chairman, Jeff Gleeson will be retiring in mid-2019, after many years on the DSC, we would like to thank members and staff for their invaluable assistance during our time on the Committee and wish members and staff all the best in their transitioning to the new dam safety regime in NSW over the coming year

Brian Cooper, DSC Chair

Cadia North Tailings Dam. A slide failure occurred in a section of the dam in March 2018 due to a local weakness in the foundation undetected during site investigations. A containment bund has been built downstream to contain any subsequent tailings flow and investigations are continuing to determine appropriate remedial options


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1. Charter

1.1. Why do we have a Dams Safety Committee (DSC) in NSW?

In the 1970’s, international concern over several major overseas dam failures led to the Australian National Committee on Large Dams (ANCOLD) raising the need for dam safety regulation across Australia. There was also significant consideration by the NSW Government as to the extent of mining that should be permitted adjacent to Sydney’s major water storages. Against this background, the NSW Government constituted the NSW Dams Safety Committee (DSC) under the NSW Dams Safety Act, 1978.

Similar legislation has been progressively implemented interstate and overseas on a basis best summed up by Jenny Bacon (UK Health and Safety Executive Director General, 1999) who noted that “It is the nature of risk that, frequently, those who create the risk do not bear its consequences or the wider costs. Therefore, the market does not function properly as a distributive mechanism. The State must intervene to regulate risk”.

1.2. What Legislation defines our Functions?

The DSC has statutory functions under the Dams Safety Act 1978 and Mining Act 1992. This will continue to be the case throughout the next year until the new Act arising out of the passage through parliament in September 2015 of the Dams Safety Bill 2015 is fully implemented. It will remain business as usual for the DSC until the new Act is so implemented.

1.3. What are the Functions of the DSC?

Amongst other things, the DSC is required to maintain a surveillance of prescribed dams, to examine and investigate the location, design, construction, reconstruction, extension, modification, operation and maintenance of prescribed dams, to obtain information and keep records on dams and to formulate measures to ensure the safety of dams in NSW. It "prescribes" those dams which if failed have a potential to threaten downstream life, cause extensive property or environmental damage, or have a severe impact on the public welfare.

At 30th June 2019 there were 410 prescribed dams-see Appendix B and also the included map following Appendix B. For prescribed dams, the DSC adopts a monitoring role to ensure the dam owners and organisations (e.g. mining companies) undertaking significant activities near their storages, conform to appropriate safety benchmarks throughout each dam’s life.

The DSC’s aim is that risks from dams to the community and the environment will be tolerably low for all prescribed dams. In this context, a "safe" dam, or associated activity, is one that complies with the DSC's safety benchmarks.

Woodlawn Tailings Storage Facility 4. This 25m high, 2500ML capacity earthen dam was completed in 2018 to provide capacity for the new mining venture at Woodlawn mine to the north east of Canberra. The dam is requires to store tailings from workings of new ore deposits and reworked tailings from existing dams at the site.


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2. Access and Contact The DSC’s access and contact details are outlined in the inside front cover of this report.

3. Aims, Objectives and Values

3.1. Mission and Objectives

In interpreting its legislative charter, the DSC has adopted as its mission “to ensure the safety of dams”.

Relevant to this mission statement, the objectives of the DSC are to: � Protect the safety, welfare and interests of the community from dam failure by formulating measures to ensure

that risks from prescribed dams remain tolerable over the long-term, that the risks are regularly reviewed, and further reduced if reasonably practicable;

� Maintain an ongoing surveillance of prescribed dams and their safety throughout each dam’s life; � Keep up-to-date on all relevant aspects of dam safety management; � Protect the security of dams and their stored waters from the effects of mining or other activities; � Inspire confidence in our stakeholders and be recognised for our technical excellence; and � Promote dam safety awareness through the direction, education and training of stakeholders.

3.2. Our Values

To achieve its aims, the DSC is guided by its core values of: � Safety – we integrate safety into everything we do (e.g. people, dams); � Integrity – impartial, honest, open and straightforward; � Service to stakeholders – we seek solutions and build relationships with teamwork and mutual respect; � Accountability – we take responsibility for our actions; and � Development – we strive for improvement.


ANNUAL REPORT 9

Medlow Bath Dam. DSC members and staff inspected this 20m high arch dam in November 2018 in association with a Committee meeting at Penrith. The dam was built in 1907 but still plays a part in the water supply for the Blue Mountains area 4. Management and Structure

4.1. DSC Structure and Organisation Chart

The DSC is a small independent statutory body which reports directly to the Minister for Water, Property and Housing. It has negligible assets or property. It uses staff seconded from the NSW Department of Industry and hires contract staff as required. The DSC operates through two Standing Sub-committees (Dam Surveillance and Mining), along with ad hoc Advisory Sub-committees (Policy, Hydrology and Emergency Management). The following chart outlines its organisation. Most business is dealt with initially by its Sub-committees, which report to Committee meetings.

Dams Safety Committee Organisation Chart (As at 30th June 2019)

Dams Safety Committee Review / set DSC policies

Review / oversight DSC operations Approve DSC actions / procedures

Chair Brian Cooper Deputy Chair

Jeffrey Gleeson Members

Sam Banzi, Norm Himsley, George Samios, John Sukkar, Michael Thornton

DSC Executive DSC Policy Subcommittee Acts for the Committee between Committee meetings on critical matters or emergencies & meets regularly with the Minister’s Office

Advises on policy development

Brian Cooper, Jeffrey Gleeson, Chris Salkovic

Brian Cooper, Jeffrey Gleeson, Norm Himsley, Chris Salkovic

Chris Salkovic

Executive Engineer (and Secretary for DSC meetings)


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Surveillance Sub-committee Mining Sub-

committee Hydrology Sub-committee

Emergency Management

Sub-committee Information

Systems Administration

Maintains a surveillance of dams. Recommends relevant policies and actions.

Oversights mining near dams. Recommends relevant policies and actions.

Advises on hydrological matters. Recommends relevant policies and actions.

Advises on emergency matters relating to dams. Recommends relevant policies and actions.

Recommend / oversight / implement DSC Information System matters.

Recommend / oversight / implement DSC Administration matters.

Chair Norm Himsley

Members Tom Reed

John Sukkar Jeffrey Gleeson Chris Salkovic Daniel Turnbull

Secretary Jason Porter

Chair Norm Himsley

Members Ian Landon-Jones

Chris Salkovic Peter Dupen

Secretary Bill Ziegler

Chair Norm Himsley

Members Peter Cloke Ian Cordery

Janice Green Nanda Nandakumar

Secretary

Chris Salkovic

Chair Sam Banzi Members

Belinda Davies Martin Dwyer

Secretary

Chris Salkovic

Chris Salkovic Chris Salkovic

Uma Maheswari Uma Maheswari Renee McDonald

Engin Hizbas

Heather Middleton Heather Middleton

In routine matters, the Executive Engineer and standing Sub-committees act for the DSC, while its Executive (Chair, Deputy Chair and Executive Engineer) deals with urgent business or emergencies between DSC meetings. Policy initiatives originate at any level, but are developed by the Policy Sub-committee before submission for DSC endorsement.


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4.2. Sub-committees

There are two standing Sub-committees, one on dam Surveillance and one on Mining. There are three ad-hoc Sub-committees, on Policy, Emergency Management and Hydrology, which meet as required. Membership of the Sub-committees is outlined in the DSC’s organisation chart.

The Executive Engineer, Mr Salkovic has been appointed to each of the Sub-committees for his technical input, and to provide effective liaison between the Sub-committees and the Committee. He also provides an important role of main liaison with dam owner personnel and other principal stakeholders, with routine liaison delegated to the relevant DSC engineering / technical staff.

4.3. Meetings The Committee held eight normal meetings during the year, of which seven were at Parramatta and one at Penrith, in association with dam inspections. Attendance at Committee meetings was as follows:-

� Mr B. Cooper (Chair) attended 8 out of 8 � Mr J. Gleeson (Deputy Chair) attended 8 out of 8 � Mr S. Banzi attended 7 out of 8 � Mr Bill Barraclough attended 2 out of 4 (retired at end of 2018) � Mr N. Himsley attended 7 out of 8 � Mr M. Thornton attended 6 out of 8 � Mr G. Samios attended 7 out of 8 � Mr J. Sukkar attended 8 out of 8

There were 8 Surveillance, 8 Mining, 1 Emergency Management and no Policy or Hydrology Sub-committee meetings during 2018/19.

Wentworth Falls Lake Dam. This 10m high embankment dam, owned by Blue Mountains Council, was inspected by DSC members and staff during a country meeting in November 2018, The dam was built in 1906 and upgraded in 1991 and 2003 to meet upgraded design standards to continue its use as a recreational facility


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4.4. Committee Members

As at 30 June 2019, the DSC had seven part-time members (with two other vacant positions). All are appointed by the Minister, with all but one of the members nominated for their experience in dams engineering (as required under the Dams Safety Act 1978) and one other member typically for experience in coal mining.

Committee membership during 2018/19, with brief member biographies, was as follows:

Brian Cooper, BE (Hons), MEngSc, GradDipEngMgt, MIEAust, CPEng (appointed to July 2019). Chair from 1 April 2009, Nominee of Engineers Australia. Initially appointed in 1997. In 2006 Brian retired from his position as Principal Engineer, Dam Safety, with the then Department of Commerce and now practices as a private dam safety consultant with over 40 years water industry experience including extensive dam design works with the Department of Public Works and Services and the Water Resources Commission.

Jeffrey Gleeson, BE Civil, FIEAust, CPEng (appointed to July 2019). Deputy Chair (re-elected in February 2019), Nominee of Hunter Water Corporation. Initially appointed in 1990. Jeff is Senior Consultant with hunterh2o. He has over 35 years’ experience in the water and waste-water field with involvement in various aspects of dam engineering and structural design. Jeff is a long serving member of the DSC's Surveillance Sub-committee. He also lectures part-time in engineering at the University of Newcastle.

Sam Banzi, BEngT (Civil), MEng, MIAM (appointed to July 2019). Nominee of WaterNSW. Initially appointed in 2016. Sam is currently the Manager Asset Engineering and Dam Safety within WaterNSW and has more than 20 years of experience in engineering, investigation, surveillance, construction and whole of life planning of dam structures. Sam's recent experience as a senior dams practitioner has been obtained from large businesses including Snowy Hydro Limited, Hydro Tasmania Ltd and SA Water Corporation. Sam is responsible for the overall management of dam safety within WaterNSW and was previously a member of the DSC's Surveillance Sub-Committee from 2007 to 2012.

Bill Barraclough, BE (Mining) (appointed to July 2019). Nominee of Minister administering the Mining Act. Initially appointed 2014. Bill has 20 years operational experience in coal mines, predominantly in the southern coalfields of NSW. For the last 15 years he has worked with the Mine Safety Resource Regulator and currently holds the position of Principal Inspector Coal and Petroleum. He was the Chair of the DSC’s Mining Sub-Committee until his retirement at the end of 2018.

Norm Himsley, BE (Hons), MEngSc, GradDipMgt, MIEAust, CPEng (appointed to July 2019). Nominee of Engineers Australia. Initially appointed in 2009. In 2009, Norm retired as Executive Engineer of the DSC and now practices as a private dam safety consultant. He has over 45 years’ experience in the water and construction industry and extensive involvement in the investigation, design and construction of dams. He is Chair of the DSC’s Surveillance Sub-committee and Mining Sub-Committee. Norm also sits on two current ANCOLD working group committees, and previously chaired its Professional Development Working Group.


ANNUAL REPORT 13

George Samios, BE (Hons), MEngSc, MIEAust, CPEng (appointed to July 2019). Nominee of Minister for Finance, Services and Property, (administering the Public Works Act) George has over forty years of expertise in investigation and the design of major dams, weirs and water supply. He has vast experience in all phases of design processes from concept and feasibility studies through to final design and contract documentation to technical liaison during construction and commissioning. George has also particular expertise in dam safety management, reviews and procedures including the preparation of compliance documentation such as surveillance reports, O&M Manuals and Dam Safety Emergency Plans. He is currently the designated dam safety engineer for a number of NSW Local Government authorities.

John Sukkar, BE (Civil), MIEAust, CPEng (appointed to July 2019). Nominee of WaterNSW. Initially appointed in December 2014. John is the Manager Dam Safety (and Acting Manager Technical Services) with WaterNSW. He is currently responsible for the safety management of dams owned by WaterNSW, a state owned corporation. He has over 25 years’ experience in the investigation, design, construction and dam safety management of dams, weirs, hydraulic regulations structures, fishways and other civil works. John has been a member of the DSC Surveillance Sub-committee since 2011.

Michael Thornton, BE (Civil), MBA (appointed to July 2019). Nominee of Snowy Hydro. Initially appointed in October 2017. Michael is the Manager Engineering at Snowy Hydro Limited. His role includes dam safety management of SHL's fleet of dams. Michael has 20 years’ experience in project/construction management as well as asset and engineering management.

4.5. Committee Staff

The Committee is assisted by a full-time equivalent staff of seven, with most employed through NSW Dept. of Industry and with temporary contract staff assistance as required. Given the extensive workload of the DSC’s activities, this staff group provides an effective and efficient service to the DSC’s functions. During the year the DSC staff comprised:

Executive Engineer: Chris Salkovic BE (Civil), (started January 2017). Chris has close to 25 years of Water Industry experience including extensive involvement in asset management, operations and maintenance management, project and program management.

Surveillance Engineer: Jason Porter BE (Civil), GradCertEngMgt, MIEAust Jason is a professional engineer who started working life in the Metropolitan Water Sewerage and Drainage Board (now the Sydney Water Corporation). He has a background in science-based non-destructive testing research, development of instrumentation, software and analysis techniques, and application of these in industry. Prior to joining the NSW DSC in 2016, Jason spent 11 years as a Dam Surveillance Engineer in State Water and WaterNSW.


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Information Systems Officer: Uma Maheswari BSc (Seconded 2001) Uma has over 15 years of experience on data and information relating to NSW Dams

Tailings Dam Engineer: Engin Hizbas BE, BE, MIEAust, CPEng (seconded 2003). Engin has over 30 years of experience in investigation, design, construction and project management in civil engineering and dams.

Manager, Mining Impacts: Bill Ziegler BE (started April 2008). Bill is a mining engineer and has over 30 years of experience in the NSW coal industry.

Mining Regulation Officer: Heather Middleton BSc, MSc (Hons) (started May 2009). Heather has over 25 years’ experience in petroleum and mining industries specialising in geochemistry and hydrogeology.

Administration Assistant: Renee McDonald (Started February 2018).


ANNUAL REPORT 15

5. Summary Review of Operations

5.1. Major Achievements for 2018/19

During the year the following milestones and deliverables were attained:

� Good progress in reducing the risks posed by dams in NSW, including amongst other projects and matters: o Completion of upgrading works at Bethungra and Tenterfield Dams ; o For other local water utility (LWU) dams, detail design studies are underway on Dumaresq Dam and upgrade

construction programmed for completion in 2020 on Winburndale Dam; o Continuation by WaterNSW of the detailed portfolio risk assessment (PRA) of its substantial portfolio of

metropolitan large dams; o Completion of the Stage 2 upgrade construction for Keepit Dam involving the post-tensioning strengthening

of the gated concrete spillway section; and o Continued progress by Snowy Hydro Limited in investigations for the PRA of its portfolio of dams.

� Good compliance with core business activities (see Table 5.2); � Successful rearrangement of the DSC’s office and associated digital scanning and storing of DSC information to

suit the new office area;

� Development of risk based investigations and approvals for a number of technically challenging applications for coal mining near dam storages, all of which assisted in allowing 35 million tonnes of coal to be extracted from Notification Areas around prescribed dams (the same as the previous year’s substantial, recent record tonnage);

� Provision and running of four DSC training courses for dam operators in dams safety and surveillance matters at Port Macquarie (3) and at Port Stephens.

� Provision of principal training assistance for three other dam safety and surveillance courses, each of 2-3 days duration, for SunWater Limited in north Queensland , and BHP at one of its large mines in central QLD;

� Review of 90 Surveillance Reports;

� Inspection by DSC members and staff of 37prescribed dams and basins and several non-prescribed ones (usually only done as part of investigations for consideration of whether prescription might be required);

� Auditing of submitted design documentation for a significant number of water and tailings dam projects;

� Auditing of a significant number of submitted dambreak and potential loss of life (PLL) studies;

� Dealing with over 1,700 pieces of formally documented correspondence.

5.2. Budget Highlights

A summary of the DSC’s financial performance is shown in Table 5.1 with full details given in Section 10 of the report. Budgeted expenditure is used as the performance yardstick.

Table 5.1 – 2018/19 Budget Highlights

Item $000

Budget (Expenditure & Revenue) 1,599

Actual Expenditure 1,753

Actual Revenue 1,840

5.3. Performance Indicators

During the year the DSC monitored performance indicators, which gauge the achievement of its objectives, as shown in the following Table 5.2 and Figure 5.1. These indicators illustrate how the DSC has effectively managed a substantial workload within its modest budgetary program. Due to the nature of the DSC’s work, and the relatively small size of its organisation, quantitative indicators are often not entirely appropriate and some of its significant indicators are therefore qualitative.


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Table 5.2 - DSC Performance Indicators

# PERFORMANCE TARGET PERFORMANCE INDICATOR RATING

1 Owners programs, agreed by DSC, for safety

improvements to significantly high risk dams

Percentage of significantly high risk dams with

agreed programs 94% (Good)

2 Follow up action taken within 3 months Percentage performance 90% (Good)

3 Reports/programs review & respond < 3 mths Percentage performance 70% (Satisfactory)

4 Yearly inspections of high risk dams Number inspected this year 7 (Satisfactory)

5 5-yearly inspections of lower risk dams Number inspected this year 30 (Satisfactory)

6 Update DSC information material every 2 yrs Time since last update issued Website updated

(Very Good)

7 Provide at least one dam safety education

course in NSW each year Number of courses arranged and run this year 4 (Very good)

8 Compliance with approved DSC budget Degree of deviation to budgeted expenditure (under

or over)

9.6% over (includes

in-kind

contributions)

(good)

9 Surveillance Sub-committee Based on policy progression, reports reviewed and

follow ups

90 Surveillance

Reports (Good)

10 Mining Sub-committee Subjective based on monitoring compliance, matters

followed up and mining impacts as predicted 90% (Good)

! Process all Applications received Percentage of applications received finalised 100% (Excellent)

! Review all monitoring data received Percentage performance 90% (Good)

! Process all SMP / Part 3A / Titles Percentage performance 95% (Very good)

11 Emergency Management Sub-committee

Subjective based on policy progression, coordination

of matters and emergency plans implementation and

updating.

Unsatisfactory due

to internal

rearrangements in

SES

12 Compliance with Records Management

Standards

Subjective based on progression in updating

procedures and systems, and programs achieved Good

13 Administration Subjective, based on meeting HR, accounting and

logistical needs of the DSC Satisfactory


ANNUAL REPORT 17

Figure 5.1-DSC Summary Statistics

26502950

23002000 2000

1710 1830 1888

$0

$500

$1,000

$1,500

$2,000

$2,500

0500

100015002000250030003500

11/12 12/13 13/14 14/15 15/16 16/17 17/18 18/19

$,000

Num

bers

Correspondence Expenditure

0

5

10

15

20

25

30

35

40

0

5

10

15

20

25

11/12 12/13 13/14 14/15 15/16 16/17 17/18 18/19

Tonn

esofcoa

l(millions)

MiningAp

plica:

onsP

rocessed

Mining Applica5ons Processed Tonnes of coal

346

360372 376

383 378 380390

400408 410

310320330340350360370380390400410420430

08/0909/1010/1111/1212/1313/1414/1515/1616/1717/1818/19

PrescribedDams

Dam

Num

bers

2018/19 Expenditure includes In-Kind Contribution and Crown Assumed Liability Expenses


18 ANNUAL REPORT

6. The Future

6.1. Dams Safety Management

The DSC expects the number of prescribed dams, detention basins and retarding basins in NSW to generally grow in the long term (especially basins) and that existing dams and basins will continue to require safety improvements to meet community expectations. The DSC’s main objective is to ensure that all prescribed dams and basins present a tolerably low risk to downstream residents, property, the environment and associated community interests.

Gosling Creek Dam. Orange Council has undertaken a dambreak study during the year for this old 8m high concrete gravity dam to see if downstream creek realignment works can prevent this dam from posing a dambreak threat. With the passage of the Dams Safety Bill 2015 through the NSW Parliament in September 2015, the DSC will continue working in close partnership with the NSW Government during the next year in the necessary and extensive work required to implement the new Act. Notably the Minister’s media releases about the passage of the Bill stated that it will remain business as usual for the DSC until the new Act is fully implemented and that dam owners must continue to comply with any requests from the DSC until the new Act is so fully implemented. Regarding other activities and functions, the DSC will in particular:

� Continue to implement and use its risk based dam safety policy, incorporating currently 22 Guidance Sheets on dam safety requirements;

� Continue to liaise with other NSW Government safety, environmental and economic regulators, to ensure that DSC requirements not only fit within a consistent regulatory framework (and one which incorporates risk management) but also keep in touch with national and international practices;

� Continue close liaison with dam safety regulators in other States including contributing to the annual Australian dam safety regulators’ meeting;


ANNUAL REPORT 19

� Continue to monitor activity programs for safety improvements to NSW dams identified as not meeting DSC safety requirements (see Tables7.5 & 7.6);

� Continue to work with dam owners in assessing the priority and urgency of safety improvements and activities, in order to achieve the optimum risk reduction with available resources and within the DSC’s required time frames;

� Continue to support research into dam safety risks and associated matters;

� Work with NSW dam owners to ensure appropriate dam emergency and security arrangements are in place, with Dam Safety Emergency Plans regularly updated and exercised. Liaise with the State Emergency Service (SES) to facilitate these arrangements;

� Continue to ensure dam owners have in place current Operation and Maintenance (O&M) Manuals for their dams and in particular for gated spillway dams and tailings dams;

� Maintain liaison with NSW dam owners and continue the emphasis on education, including providing training courses for dam owners’ personnel. The DSC will also arrange and/or facilitate presentations by staff and members at meetings and conferences on dam matters as deemed required, and provide input to ANCOLD Guidelines;

� Continue to advise dam owners of the value of installing rainfall and flow monitoring equipment to enhance flood warning, and to assist in flood analysis and design;

� Review and update DSC internal management procedures and also its databases;

� Continue to investigate the vast number of non-prescribed dams and retarding basins to determine if any of these dams present a risk to the community and thus need to be prescribed;

� Continue corporate (organisational) membership of ANCOLD and continue memberships and subscriptions to journals of various international dam safety organisations to ensure the DSC remains up to date and conversant with the latest relevant national and world practices in dam engineering.

Woodford Creek Dam. DSC members and staff inspected this 16m high concrete arch dam in November 2018 in conjunction with a DSC country meeting. The dam was built in 1928 and still forms an integral part of the water supply system in the Blue Mountains area.


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6.2. Mining Management near Dams

The number of applications to mine within Notification Areas has reduced from the historical high of 2012/13 to a more stable number over the last three years. During 2018/19 approximately 35 million tonnes of coal were extracted from Notification Areas around prescribed dams. This was notably similar to the previous several years very large tonnages.

The DSC’s objective is to advise on mining regulation so as not to unnecessarily restrict extraction of NSW mineral resources. It continues to ensure that mine owners develop a comprehensive scientific understanding of the effects of mining on stored waters and dams in order that mining within Notification Areas occurs with negligible impact to existing infrastructure. Through time, DSC staff members have been developing more sophisticated risk analysis tools as an aid to managing the impacts of mining. In addition, an expanding knowledge base and advances in technology have resulted over time in the DSC having improved confidence to support the extraction of extra coal from under and near NSW storages, in situations where mining would not have been approved in earlier years.

The DSC’s ongoing initiatives to achieve its objective are to:

� Investigate and progressively implement applications of risk management to various aspects of mining developments, and monitor practice and update guidelines accordingly;

� Ensure adequate protection of dam walls and stored waters by reviewing the maximum extent of ground movements induced by coal mining and, if necessary, increasing the size of Notification Areas;

� Promote compliance within the mining industry, and understanding within other Government agencies, of the DSC’s mining management requirements through involvement in planning processes, and ongoing interaction with stakeholders.

6.3. Administration and Information Systems

As it did in 2018/19, the DSC will maintain a commitment in the coming financial year to ongoing implementation of strategic planning within its business planning process, with procedures and practices formalised and updated as necessary. The DSC will continue necessary regular upgrading of desktop hardware and software within its information systems to meet increasing demands. As occurred in 2018/19, new and updated features will continue to be added to the DSC databases and existing parts (e.g. GIS, Notification Areas, overdue reports) will be expanded and consolidated. Training programs will continue to be conducted for staff and members to facilitate effective and safe work practices (e.g. various computer program courses, finance processes, audit courses and/or other work/health/safety matters). Progressive updating of the new DSC’s office will continue to maximise effective use of the resource. Out-dated documents will continue to be scanned and archived to maximise usable storage space within the DSC’s office.

6.4. NSW Dams Safety Review

A substantial passage of time has elapsed since the Dams Safety Act 1978 and the associated Dams Safety Committee (DSC) were established. In 2013 the NSW State Government embarked on a review of NSW dams safety in general and its regulatory process. That work culminated with the passage of the Dams Safety Bill 2015 through the NSW parliament during September 2015 and the ensuing Bill’s assent. Notably the Minister’s associated media releases stated that it will remain business as usual for the DSC until the new Act is fully implemented, that the new Act’s implementation will take some considerable time and that dam owners will continue to be regulated by the DSC until the new Act is fully implemented.

On behalf of the government, DPI Water initiated the implementation process for the new Act with the formation of an interim advisory committee in October 2016 which will work separately to the DSC on developing the redefined dam safety standards and undertaking other regulatory and policy development in relation to dam’s safety under the new Act. It is expected that the advisory body will liaise at various intervals with the DSC about the current dam’s safety standards and requirements and regulatory approach. The DSC looks forward to continuing in partnership with the government in the necessary and extensive work required to fully implement the new Act over the coming year.


ANNUAL REPORT 21

7. Review of Operations

7.1. Dams Safety Management

7.1.1. What Dams are under Surveillance? The DSC is required to maintain a surveillance of prescribed dams; to examine and investigate the location, design, construction, reconstruction, extension, modification, operation and maintenance of prescribed dams; to obtain information and keep records on dams and to formulate measures to ensure the safety of dams in NSW. Although the state has tens of thousands of dams, predominantly farm dams, the DSC interprets its charter as being to protect life and significant property, environmental and other community interests. Therefore, the DSC only “prescribes” and maintains surveillance of the safety of those dams with potential for significant failure consequences, as listed and detailed in Appendix B (410 dams as at 30th June 2019).

7.1.2. Policies and Procedures that Apply to Dams Safety Management After being informed of a proposed dam, the initial DSC decision is on the need, or otherwise, for prescription of the dam. This will normally be based on the Consequence Category of the dam, which in turn is based predominantly on the estimated potential loss of life in the event of the dam’s failure. These matters are outlined in DSC Guidance Sheet DSC1A DSC Background, Functions and Operations. Then for prescribed dams, as shown in Table 7.1 below, the DSC has a range of policies and procedures that facilitate its interactions with dam owners and other affected organisations at all stages of the life of that dam. This is outlined further in DSC’s Guidance Sheet DSC2B Documentation and Information Flow over Dam Life Cycle.

Table 7.1 - Interaction of DSC over Dam Life Cycle

Phase Interaction

Investigation Owners provide proposed dam details DSC decides on prescription and provides ongoing requirements (see DSC2B)

Design DSC reviews suitability of design team DSC requires design report and reviews major design standards (does not review details)

Construction DSC requires designer involvement during construction in particular to approve any changes DSC requires Construction Report and Construction Completion Certificate, certifying the designer’s agreement with changes during construction

Commissioning DSC requires Surveillance Report one year after construction DSC requires Operation & Maintenance Manual DSC requires Dam Safety Emergency Plan if downstream lives at risk

Operation

DSC requires regular surveillance and reporting by the owner DSC conducts random checks of compliance DSC requires submission of Surveillance Reports at regular intervals (usually 5 yearly) DSC requires Safety Reviews at regular intervals (usually 15 to 20 year intervals)

Modifications DSC requirements similar to that for new dam

Decommissioning DSC reviews proposal DSC requires decommissioning report

For further information on DSC dam safety regulation policies, refer to the DSC’s Guidance Sheets listed on the following page in Table 7.3 and available on our website www.damsafety.nsw.gov.au for downloading.

Table 7.2 – Amendments to DSC Information

Information Source Amendment Updated

Database Advisory letters April 2019


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Table 7.3 - Guidance Sheets for Dams Safety

Document Description Update Date

DSC1A DSC Background, Functions and Operations June 2010

DSC1B Background to DSC Risk Policy Context June 2010

DSC2A Dam Safety Management System (SMS) June 2010

DSC2B Documentation and Information Flow over Dam Life Cycle June 2017

DSC2C Surveillance Reports for Dams June 2010

DSC2D Demonstration of Safety for Dams June 2010

DSC2E Some Legal Considerations for Dam Owners June 2010

DSC2F Operation and Maintenance for Dams June 2010

DSC2G Emergency Management for Dams Dec. 2010

DSC2H Dam Security June 2010

DSC2I Community Consultation and Communication (CC&C) June 2010

DSC3A Consequence Categories for Dams November 2015

DSC3B Acceptable Flood Capacity for Dams June 2010

DSC3C Acceptable Earthquake Capacity for Dams June 2010

DSC3D Reliability of Spillway Flow Control Systems June 2010

DSC3E Flood Retarding Basins June 2010

DSC3F Tailings Dams June 2012

DSC3G General Dam Safety Considerations June 2010

DSC4A Mining Near Prescribed Dams – Administrative Procedures March 2011

DSC4B Mining Near Prescribed Dams – Mining Applications June 2010

DSC4C Mining Near Prescribed Dams – Management and Monitoring Matters June 2010

DSC4D Mining Near Prescribed Dams – Contingency Plans June 2010

7.1.3. 2018/19 Dams Surveillance Matters

The DSC continually reviews its list of prescribed dams in the light of new proposals, changed conditions, staff inspections and information supplied, to ensure that only dams with the potential for significant or higher failure consequences are prescribed. During 2018/19 there was a net increase of 2 prescribed dams, giving a total of 410 prescribed dams at June 2019 (see Appendix A Summary, Appendix B list and the map following Appendix B).

For proposed prescribed dams and dam modifications, the DSC requires dam owners to provide design information for its review before construction. A significant number of such submissions were processed during 2018/19. The DSC usually confines its review to assurance that major safety criteria (e.g. flood capacity, embankment zoning, filter provisions) are satisfied, and that the designers are competent, though the DSC may challenge any design aspect that is of concern. The DSC also requires the submission of copies of design reports and it also requires independent expert peer reviews for designs, upgrades and safety reviews of High and Extreme Consequence Category Dams.

The DSC requires the designers’ involvement in the dam construction process, including approving design changes so that the “as-built” design is sound. DSC staff members also liaise with dam owners’ personnel and carry out construction inspections.


ANNUAL REPORT 23

Upon completion of construction, the DSC requires dam owners to submit work-as-executed (WAE) drawings and the “construction completion certificate” (certifying the designer’s approval of any changes) for the DSC's records.

At a reasonable time after completion of construction, the DSC requires dam owners to submit a Construction Report for future reference.

The DSC then requires Surveillance Reports summarising the behaviour of the dam since construction, to be submitted. The first report is to be submitted after first filling of the dam, which is a critical phase in dam safety, but no later than one year after construction. Thereafter, Surveillance Reports are required at not more than five-yearly intervals. Annual update reports are required for mine tailings dams in the cases where substantial changes to the structure of the dam can occur, and at two and a half yearly intervals for tailings dams where no significant changes to the dam are occurring.

These Surveillance Reports provide information on dam safety status and are checked by DSC staff and the Surveillance Sub-committee who provide summary advice to the Committee for discussion and/or endorsement. The reports enable the DSC to continually monitor whether dam owners are responsibly managing their dams at all stages of the lives of those dams. The reporting extent varies, with comprehensive reporting required for Extreme Consequence Category dams; down to brief pro-forma reports for Low Consequence Category dams (see Guidance Sheet DSC2C).

During 2018/19, the DSC received and reviewed 90 dam Surveillance Reports (see Appendix A). This is close to the average targeted number to be reviewed and has thus helped to minimise the risks that a dam problem may go undetected. However, difficulty still lies with timely submission of reports by some dam owners. To prevent a serious backlog from developing, the Committee can and does issue notices under Section 15 of the Dams Safety Act to those owners where Surveillance Reports or other required investigation reports are more than two years overdue without a valid reason. Surveillance Reports are stored in the DSC’s record system and progressively incorporated into the DSC database. Provision of electronic copies of each report is now a standing requirement. The DSC considers that the content and presentation of Surveillance Reports is of a reasonably high standard and that the majority of owners are responding in a positive and responsible manner to the DSC’s requirements.

Redbank Village Dam. DSC members and staff inspected various new dams and retarding basins in the north Richmond area in association with a Committee meeting at Penrith in November 2018


24 ANNUAL REPORT

The DSC continued with and strengthened its regular programmed staff and Committee member inspections of dams and discussions with owners, throughout the State. Inspections by DSC members in conjunction with the country meetings of the DSC also continued. A country meeting was held in Penrith with associated inspections in the lower Blue Mountains area. Thirty-seven prescribed dams were inspected during 2018/19, which was just over 9% of the total number of prescribed structures. The DSC inspected seven of the current top 15 high-risk dams during 2018/19. Continued emphasis will be placed on inspections of prescribed dams by DSC staff and members every year to assist in checking that recommendations within Surveillance Reports are being carried out, and that mining activities within and near dams are not having adverse effects on the dams. These inspections and country meetings are also essential in the long-term to check the general safety standard of each dam, its consequence category, and the actual performance of each dam owner in complying with DSC requirements. Any non-compliance with requirements or deficiencies in programs detected is brought to the attention of the owner's representative(s), and any concerns discussed on site. The inspections also provide useful background knowledge against which Surveillance Reports can be evaluated and assessed by the DSC.

During 2018/19 the dam surveillance statistics achieved were good overall. The Committee acknowledges here its high commendation of the DSC’s Surveillance and support staff for the very large workload completed in the last 12 months, including all reviews and audits of submitted reports completed in a timely manner.

7.1.4. Examination and Investigation of Dams Safety

Dam owners are legally responsible for the safety of their dams and to ensure the risks from their dams are tolerable. The role of the DSC is to ensure that dam owners discharge this responsibility and that community interests are adequately protected.

The DSC views the risk assessment approach of the ANCOLD Guidelines on Risk Assessment 2003, in conjunction with the national standard AS/NZS ISO 31000:2009 Risk Management Principles & Guidelines, as providing a good framework for comprehensive examination and investigation of dam safety over the whole range of potential failure situations and a better understanding of relative risks and consequences. Accordingly, the Government endorsed in August 2006 a revised dam safety regulatory policy framework, the Risk Management Policy Framework for Dam Safety, which integrates the traditional engineering standards based approach to safety with risk assessment methods in determining the safety status of dams in a more rational manner.

The process of risk assessment assists in evaluating the relative safety of each dam, to assess risk reduction options and to assign priority and urgency to any remedial actions required. Risk assessment can better clarify safety and thus provide for more informed decision-making as well as providing upgrading options based logically on risk, consequences and costs. Risk assessment requires that the analysis team work with the decision-maker, and communicate appropriately with the affected community, to arrive at an informed overall judgement of the safety requirements for a dam. Several risk assessments were submitted during the year. Two substantial portfolio risk assessments (PRAs) are currently in progress, one by WaterNSW for its metropolitan dams and one by Snowy Hydro Limited.

Various other assessments and reports were also submitted to the DSC for auditing, including design documentation for a number of dams (mostly pertaining to augmentations). To assist staff with their reviews of those reports a report review checklist has been previously developed to ensure that the reviews have covered all the DSC’s requirements, including the need for independent peer review of reports for all High and Extreme Consequence Category dams.

The DSC furthermore will continue its general policy of judging each case on its merits by considering any dam safety proposal that is soundly based, aligned with accepted practice, and would result in a demonstration of tolerable risks.

Guidance Sheet DSC1B Background to DSC Risk Policy Context requires dam owners to keep dam risks under review. The safety of a dam is to be reviewed whenever the DSC determines that a review is needed or at a minimum every 15 years (for Extreme and High Consequence Category dams) or 20 years (for Significant Consequence Category dams).

An owner is to submit its conclusions on a dam’s safety, or proposals for dam safety improvements to the DSC for review. For all supporting data interpretations, analyses, calculations, judgements and conclusions, the DSC relies on the knowledge, skill and diligence of the owner’s professional advisors. This policy will not prevent the DSC challenging the owner to justify any aspect of a proposal if considered necessary.


ANNUAL REPORT 25

A dam owner is to bring risks into compliance with the DSC’s safety requirements as soon as reasonably practicable and is to keep the residual risks under review and is to maintain risks as low as reasonably practicable over time. However, safety improvements required by the DSC may be implemented progressively where that would promote more effective risk reduction for the community as regards risks from dams. Short term dam safety improvements are generally required within 2 years, medium term improvements within 10 years and long term improvements are required within 20 years (see Guidance Sheet DSC1B).

Also, when required to do so, a dam owner is to demonstrate that risk to public and other interests of the community are tolerable. To be tolerable, a risk must be below the limit of tolerability and as low as reasonably practicable (ALARP). For public safety risks, risk boundaries – the limit of tolerability and the negligible level of risk – are relevant in applying the ALARP test. See Figure 7.1 below (adapted from Fig. 1 in DSC1B).

For a risk to be ALARP, the sacrifice (generally in terms of cost) required in its reduction must be grossly disproportionate to the risk reduction that is achieved and may partially be based on CSSL (Cost to Save a Statistical Life). Note that CSSL is a cost benefit analysis approach. Other criteria also need to be considered

Figure 7.1 – DSC Societal Risk Requirements: Existing Dams


26 ANNUAL REPORT

To provide background data needed for safety assessment studies, the DSC has continued to encourage dam owners and Government agencies to install and maintain rainfall/runoff and seismic monitoring equipment, and to support research into the estimation of piping risks, the derivation of extreme rainfall estimates, and the risk assessment of dam slopes and other important stability criteria.

A Dam Safety Emergency Plan (DSEP) is required by the DSC for any dam where lives are at risk from dam failure, to provide a contribution to aiding risk management. These plans apply from construction throughout the life of each dam and are aligned to SES planning for river and flash flooding. The DSC liaises with the SES and provides data and information on the highest risk and other significant risk dams, particular through the DSC’s Emergency Management Sub-committee. These developed protocols allow the SES to effectively prioritise its emergency planning for dams (see Section 7.1.9). From information received, the DSC identifies those dams with the highest risks and those with possible risks. The DSC then reaches agreements with owners on needed safety improvements, or the activities needed to clarify safety, and a timetable for actions. Once a significant safety shortfall is confirmed, the owner is to submit a program for safety improvement. The DSC regularly updates its provisional risk group indexing of dams and the SES is informed to guide it with interim flood planning downstream of various dams. However, the DSC listing is not exhaustive as there may be dams with undetected shortfalls on safety to date. The DSC requires dam owners to undertake regular safety reviews to minimise the risk of safety shortfalls going undetected. With most attention on the dams in Tables 7.5 and 7.6, the DSC then monitors activities against the safety improvement program, which can necessarily extend over many years to allow for detailed investigations and community consultation, financing and implementation. Once again, this process continued throughout the year. About 80 dams have been modified for safety improvement following the DSC’s establishment, with some 50 in the last 18 years since 2001 as shown in Table 7.4. For some of these dams, there have been staged improvements made (including some stages before 2001, as indicated). These numbers and the table do not include any staged raisings of tailings dams.


ANNUAL REPORT 27

Table 7.4 - Dams Modified for Safety Upgrading since 2001(except tailings dams) Dam Main Safety Issue Year Completed Nature Of Upgrading

Bethungra Flood 2018 Dam buttressed with rockfill

Blowering Flood 2010 Parapet wall on dam, spillway walls raised

Bulli Upper R’way Basin Flood 2010 Embankment removed (and basin de-prescribed)

Burrendong Flood 2011 Dam & saddle dams raised

Cecil Park Basin 3A Flood/Stability 2008 Spillway enlarged, embankment stabilised

Chaffey Flood 2011; 2016 Dam raised and auxiliary spillway constructed

Chichester Flood/Stability 1995; 2004 Dam post-tensioned, abutment stabilised

Chifley Flood 2001 Dam raised and spillway post-tensioned

Clarrie Hall Flood 2014 Spillway modification works

Company Flood 2006 Spillway enlarged, embankment raised

Copeton Flood 2013 Auxiliary spillway constructed

Daintree Drive Lower Flood 2013 Spillway capacity increased (and dam de-prescribed)

Daintree Drive Upper Flood 2013 Spillway capacity increased (and dam de-prescribed)

Emigrant Creek Flood 2002 Dam post-tensioned, abutments raised

Googong Flood 1992; 2011 Dam raised, spillway stabilised

Grahamstown Flood 2001; 2005 Dam core raised, face armoured, spillway upgraded

Green Meadows Basin Flood 2003 Embankment & crest stabilised, new spillway

Hamilton Valley 5A Flood 2009 Embankment stabilised

Hume Stability/Earthquake 1997-2017(staged) Embankment / south training wall stabilised, associated works

Jerrara Creek Flood 2015 Dam decommissioned (and de-prescribed)

Jindabyne Flood 2006; 2010 New spillway and outlets

Kalingo Flood 2012 Spillway upgraded

Keepit Flood 2011 Right abutment spillway &subsidiary wall spillway

Kensington Pond Flood 2018 Dam augmented/strengthened

Lake Pambulong Basin Flood 2014 Extra spillway capacity provided (basin de-prescribed)

Mardi Earthquake/Flood 1991; 2011 Embankment stabilised; spillway & outlet augmented

Moore Creek Flood 2007 Dam buttressed

Muirfield Golf Club Flood 2013 Spillway enlarged

Pacific Palms Flood 2013 Spillway enlarged (and dam de-prescribed)

Petrochilos Flood 1989; 2006 Spillway upgraded

Prospect Earthquake 1997; 2014 Upstream dam embankment stabilised

Quipolly Dam Flood 2013 Dam raised, spillway augmented

Redbank Creek Flood 2011; 2014 Outlet conduit for minor flood load; dam wall lowered

Rocky Creek Flood/Piping 2010 Embankment upgrade to resist piping

Rylstone Flood 2003 Auxiliary embankments removed

Sooley Flood 2005; 2010 Dam raised & buttressed, new spillways

Split Rock Flood 2012 Parapet wall modification works completed

Spring Creek Flood 2011 Bank strengthened and raised, spillway augmented

St Joseph Sch. R Basin Flood 2001 Bank stabilisation and new spillway

Suma Park Flood 2016 Auxiliary spillway, dam strengthened / raised, storage raised

Tenterfield Stability / flood 2018 Dam buttressed

Tilba Flood/Stability 1997; 2003 Dam wall raised; toe drained

Warragamba Flood 1990; 2002; 2011 Dam tensioned & raised, auxiliary spillway, gate upgrade

Wentworth Falls Flood 1993; 2003 Dam raised, spillway augmented

Widemere Det. Basin Flood 2009 Basin raised, spillway enlarged

Winding Ck 5 Basin Flood 2011 Parapet wall on embankment

Wingecarribee Piping, Flood 2012 Piping upgrade, peat barrier flood protection

Wyangala Flood 2011 Spillway walls raised

Yellow Pinch Piping 2013 Downstream filter extension in upper crest section


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Based on current information available to the DSC, the dams and basins identified as having the highest risks pertaining to safety (or requiring some particular and important safety status checking) are listed in Table 7.5. This table also includes the year in which the apparent or possible shortfall in safety requirements was determined, and the status of the safety improvement program for each dam. Dam owners have commenced safety review studies, improvement options studies or design of improvement works for all of these dams, and the DSC monitors their progress. If owners fail to achieve satisfactory progress, the DSC works with the owners to ensure an improved outcome. Should owners not respond positively, the DSC could and has previously issued notices under Section 18 of the Dams Safety Act 1978. WaterNSW is the portfolio owner of the greatest number of large dams in this State and the DSC continued to liaise closely with WaterNSW on further reduction of risks at several of the organisation’s dams. With respect to some of its dams and projects during 2018/19, WaterNSW:

� Completed the second stage of its upgrading program for Keepit Dam involving the extensive and complex post tensioning of the gated concrete spillway section of the dam

� Continued with safety review and flood attenuation upgrading investigations for Warragamba Dam and has embarked on a priority safety review investigation work for Fitzroy Falls Dam.

� Commenced the detailed portfolio risk assessment (PRA) of its substantial portfolio of metropolitan large dams (following on from the completion in 2014 of a detailed PRA of its other large dams).

The DSC thanks WaterNSW for the cooperation it has given to the DSC in proceeding with its dams safety review and upgrading programs. There are currently 154 prescribed dams and basins owned by local government councils and other local water utilities (LWUs). Work continued during the year on a prioritised program to improve the safety of various LWU dams. Some of this programmed development is currently done through the auspices and assistance of DPI Water. Some notable examples of programmed work on LWU dams and basins during 2018/19 included the following:

� Detail design studies are continuing on Dumaresq Dam.

� Construction of the post-tensioning upgrade of Winburndale Dam is programmed for 2019/2020.

� Bethungra Dam was buttressed with stabilising downstream rockfill in late 2018;

� Construction of the buttressing upgrade of Tenterfield Dam was completed in mid-2018. In addition, the DSC continues to monitor the progress of dam owners in developing action programs for dams with minor shortfalls in safety aspects and owners’ investigations of several other dams to confirm their safety status. In mid-2015 the DSC accepted Essential Water’s submission to delay the upgrade works for its Imperial Lake Dam while alternative Broken Hill water supply security options were decided upon, as any adopted alternative water supply security option could lead to the dam’s decommissioning. In June 2016 the NSW State Government announced a decision to build a pipeline from the Murray River to Broken Hill to guarantee the town’s water security. The DSC has now endorsed Essential Water’s decision to commence decommissioning Imperial Lake Dam now the new pipeline project has been completed.

Tenterfield Dam This 15m high concrete dam was successfully buttressed by downstream concrete placement in 2018 to meet acceptable flood and seismic standards,


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Table 7.5 - Status of Upgrading Activities for Dams and Basins under DSC Particular Review (i.e. highest risk or particular circumstances as at 30th June 2019).

Dam/Basin (Note 2)

Safety Issue 2018/19 Upgrading Progress

Type Identified

Barina Park Detention Basin F 2013 Investigation/design studies and then ensuing upgrading works planned for 2019.

Cadia North TSF S 2018 Investigation continuing on remedial options

Dumaresq Dam F, S 2001 Design of upgrading being finalised.

Fairfield Golf Course Basin F 2014 Upgrade construction nearing completion.

Fitzroy Falls Dam E, S 2016 Investigations are being suitably prioritised within the owner’s current PRA program.

Floraville Road Detention Basin F 2015 Dambreak assessment undertaken. Construction of embankment toughening for flood

overtopping programmed for late 2019.

Gosling Ck Dam F 2013 Program of flood diversion and foundation evaluation investigation scheduled in 2018.

Imperial Lake Dam F, S 2000 Designs for decommissioning dam are being reviewed. (FWA)

King Park Basin F 2014 Investigation & design work for flood security upgrade scheduled during 2019/20, with the upgrade construction assumed completion in 2020.

Mimosa Rd Basin F 2014 Investigation & design work for flood security upgrade scheduled continuing with the upgrade construction to follow and assumed completion in 2020.

Nepean Dam S 2007 Awaiting finalisation of stability analysis reassessment with an expectation that a lower risk position then will likely be demonstrated. (FWA)

Palm Tree Grove Detention Basin F 2017 Flood deficiency identified at June 2017 meeting Upgrading construction planned for

2019/2020.

Stockdale Basin F 2014 Investigation & design work for flood security upgrade scheduled during 2019, with the upgrade construction assumed completion in 2020.

Warragamba Dam E 2008 Series of complex investigations and safety updating reviews close to completion and programmed for submission by the end of 2019. (FWA)

Winburndale Dam F 1995 Detailed design of chosen upgrade option completed in Sep. 2015. Programmed completion of safety upgrading scheduled in 2020. (FWA)

F - Inadequate Flood Capacity

S - Potential Structural Inadequacy

E - Potential inadequate Earthquake Resistance

FWA - Flood Warning Arrangements in place

Suma Park Dam. This 31m high arch dam, owned by Orange Council, was raised 2m for extra water supply

and strengthened to meet safety standards in 2017


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Table 7.6 - Status of Activities on Dams issued with S18 Show Cause Notices

Dam Safety Issues

Upgrading Progress Type Identified

Nil Nil Nil Nil

Table 7.7 - Dams issued with S15 Notices outstanding at 21st February 2019

Dam Owner Report required Due since

Fountaindale Kiama Municipal Council Dambreak study requested 2016

7.1.5. Flood Capacity and Hydrology

Various floods over the last few years in NSW and Australia have focussed dam owners’ attention on the security and operation of their dams. Some of these floods have caused rapid storage rises in various prescribed dams, and even resulted in the overtopping failure of Oaky River Dam in northern NSW in February 2013 (exacerbated by problems with gated spillway operation). The dam had been correctly assessed as a Low Consequence Category structure and, as expected, there was no threat to any lives and only minor environmental damage occurred. However, that incident still indicates the importance of providing adequate spillway capacity (and effective gate operation) for dam structures, even for Low Consequence Category dams where the decision for upgrading is effectively the owner’s.

World-wide inadequate flood is still one of the leading causes of dam failure or the main contributing reason for upgrades of existing dams. The main reason for the many dams world-wide having inadequate flood capacity is the steady advance in the understanding of extreme events by meteorologists and hydrologists. It is now recognised that flood estimates made some decades ago were generally too low, and analyses using current day flood estimating methods have shown numerous dams in NSW as having inadequate flood capacity. The DSC requires NSW dam owners to undertake periodic reviews of the flood capacity of their dams to see if safety improvements are needed. In NSW a number of prescribed dams are under particular review by the DSC (see Table 7.5 for example).

Floraville Road Detention Basin. This 4m retarding basin, owned by Lake Macquarie Council is programmed to have reinforced grass installed on the crest and downstream face, later in 2019, to provide suitable flood overtopping protection.

Initially, Probable Maximum Precipitation (PMP) estimates are required to define extreme storm rainfalls for each dam. These PMP events, while very rare, are plausible and several near PMP events have occurred (e.g. a record storm at Dapto in 1984 dumped 515mm of rain in 6 hours – a near PMP event). Generalised procedures from the Bureau of Meteorology (BoM) are now available in NSW for PMP storms over any catchment area and for any duration.


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The BoM also provides estimates of rainfall for more frequent storms (i.e. 1 in 1year AEP up to 1 in 2000 year AEP storms). Rainfall estimates are then converted to flood predictions by the dam owner’s hydrologists, using approaches outlined in Australian Rainfall and Runoff, produced by Engineers Australia and updated in late 2016.

DSC Guidance Sheet DSC3B Acceptable Flood Capacity for Dams provides information on the provision of acceptable flood capacity for dams. It takes into account the latest requirements and developments in the Australian National Committee on Large Dams (ANCOLD) guidelines on dam safety, including greater incorporation of risk assessment. DSC3B is limited to guidance on the means by which dam owners are to demonstrate to the DSC that the flood risks posed by their dams to community interests are tolerable or will be made tolerable following safety improvements.

In setting its requirements, the DSC has been guided by the advice of its Hydrology Sub-committee, which maintains a close liaison with ANCOLD, Engineers Australia and hydrologists from Authorities and academia throughout Australia.

7.1.6. Earthquake Capacity

Historically, earthquakes up to Magnitude 6.9 have occurred in Australia and the 1989 Newcastle earthquake (M 5.4) showed that large damaging earthquakes can occur. Seismologists indicate that major earthquakes up to M7.3 could occur anywhere in NSW and such an earthquake has about 1,000 times the power of the Newcastle earthquake.

Many overseas dams have survived nearby earthquakes up to Magnitude 8 as evidenced in the 2008 Sichuan Chinese earthquake. More recently Fujinuma Dam in Japan failed due to liquefaction induced by the March 2011 M 9 earthquake. Experience however has shown that well-constructed concrete and earth/rockfill dams on good foundations are reasonably stable during earthquake events. Fortunately, these types form the bulk of NSW prescribed dams.

Whilst it is expected that few dams are vulnerable, earthquake stability reviews are required in the regular safety reviews of prescribed dams. To provide guidance for designers and reviewers, the DSC issued its Guidance Sheet DSC3C Acceptable Earthquake Capacity for Dams. The DSC’s goal regarding seismic safety is to ensure dams are appropriately designed for seismic stability and also managed so as to achieve tolerable risks to community interests. It is for the dam owner to determine how this goal (including DSC requirements) will be achieved and to demonstrate to the DSC that the goal is achieved, or will be achieved following safety improvements.

In 2018/19 the largest seismic event in NSW was a Magnitude 3.8 earthquake located near Orange, on 22nd July 2018. No damage to nearby dams was reported. The maximum recorded seismic event in Australia in 2018/2019 was a Magnitude 5.9 earthquake located NW of Carnarvon in Western Australia on 16th December 2018.

Scarcity of long-term seismic data to use as a basis for determining earthquake design loadings for dams, along with a thinning of NSW dam seismic stations, remain a concern for the DSC. The seismic monitoring network installed on WaterNSW’s metropolitan group of dams in the early 1990’s has recorded minor seismicity in the area and has provided beneficial data for future design use on dams and other structures in the Sydney area. WaterNSW’s network complements the Newcastle network installed after the 1989 earthquake, along with some seismic stations at WaterNSW’s other dams and Snowy Hydro Limited’s dams, and the national grid installations of Geoscience Australia.

7.1.7. Safety under Non-flooding Conditions

Dams are long life structures, with the oldest dams in the world over three thousand years old, and the oldest prescribed dam in NSW, Lake Parramatta Dam, being over 150 years old. Given that the average age of major NSW dams is over 40 years; their structural safety under normal operating conditions is mostly satisfactory by current methodology. Where apparent shortfalls in structural adequacy or acceptable flood capacity have been revealed, the DSC has required owners to undertake safety reviews and to implement any consequently determined improvement action.

Particular areas of concern to the DSC include but are not limited to:

� Older earth dams, without intercepting filters to control piping and seepage. Piping causes almost as many dam failures as inadequate flood capacity with the following examples of upgrades of NSW dams to reduce the risks from piping failure:

o The upgrading of Prospect Dam, completed in 2014, involved filter works to control piping and seepage.

o Some previous examples of upgrading in regard to piping protection include Hume, Mardi, Tilba, Rydal, Grahamstown, Yellow Pinch and Rocky Creek Dams, and Cecil Park Basin 3A. Research funded partly by the DSC is helping to provide developing international practice on piping safety for old dams without modern filters. The DSC has a Guidance Sheet DSC3G General Dam Safety Conditions that provides some information and references. Analysis of a dam’s safety for this aspect is largely based on risk assessment.

o The deterioration, with time, of un-encased pressure conduits through embankments could lead to uncontrolled high-pressure leakage through the embankment and dam failure. A number of large dams have failed from this cause overseas, as have a few small dams in Australia. The DSC requires dam owners to investigate and monitor their conduits (e.g. Tumbarumba and Petrochilos Dams). This is also covered in Guidance Sheet DSC3G.


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o The need to better understand piping and slope instability risks of embankment dams. A research program initiated some years ago by the University of NSW and part sponsored by the DSC has developed valuable new understanding in this area. A procedure was developed from this research (the tool-box method) by the US Army Corps of Engineers and the US Bureau of Reclamation. This piping tool-box method has recently been modified.

o The reliability of spillway control systems, given several serious incidents and dam failures world-wide involving gate failures. There are about 20 gated prescribed dams in NSW and the DSC requires their owners to regularly review their gates’ safety and to ensure high reliability through systems upgrades, back-ups, proper operation and maintenance procedures. A DSC Guidance Sheet DSC3D Reliability of Spillway Flow Control Systems on this aspect of dam safety is available and outlines how gate reliability is to be generally considered in the assessment of a dam’s discharge control and capacity. Note that:

o Snowy Hydro Limited is currently undertaking a substantial gate reliability study on its gated dams. o WaterNSW has previously completed a gate reliability study for Warragamba Dam.

The safety of mine tailings and ash dams is usually associated with their operation, location, foundation conditions and construction methodology, which in turn are directly affected by the mine site layout and tailings placement operations. A major slide failure occurred at Cadia Mine’s Northern Tailings Storage Facility in March 2018 but the consequences mainly related to the owner’s onsite business risks. However, one recent notable overseas example was a major tailings dam failure in Brazil in January 2109 that resulted in over 300 deaths, substantial environmental and societal damages, and also major financial costs and negative repercussions on the economy. Brazilian courts and authorities have declared the mine owner as responsible for the clean-up costs and associated compensation for environmental damage from the dam failure. These costs will be substantial and, along with fines and liability claims, will run into billions of dollars, along with several mine employees, consultants and Government regulators facing manslaughter charges.

This serious incident and the widespread media coverage on it, highlight the major risks posed by dams and the special vulnerability of tailings dams, the failure of which usually has very significant environmental consequences, and sometimes loss of life. The DSC Guidance Sheet DSC3F Tailings Dams covers safety policies and management practices specific to tailings dams and references the associated ANCOLD Guidelines on Tailings Dams (2012).

7.1.8. Operation, Maintenance and Surveillance

Dams require care throughout their lives to keep them in a safe condition because materials, components and machinery deteriorate with time. Ongoing operation, maintenance and surveillance are essential and cost-effective; otherwise reduced life expectancy or failure could result (e.g. a near piping failure of a Hunter Valley tailings dam in 2003 was averted by timely intervention). In particular, proper operation is an essential component to ensure the safety of upstream-raised tailings dam. The rehabilitation works or decommissioning, as found necessary for some older NSW dams (e.g. Wellington Dam), illustrate the deterioration that can occur as dams age. Concepts developed in other industries, such as Failure Modes and Effects Analysis (FMEA), are now being introduced to dams to provide a more rational and better targeted basis for maintenance and replacement programs.

Dam safety specialists throughout the world recognise the necessity for systematic and documented operation and maintenance procedures. The ANCOLD Guidelines on Dam Safety Management (2003) set out contemporary requirements in this area, based on industry best practice, and this document provides a basis for a uniform national approach to proper operation and maintenance. The DSC has adopted these Guidelines generally (with some refinements) as its requirements, as outlined in its Guidance Sheet DSC2F Operation and Maintenance for Dams.

Shannon Creek Dam

This 51m high earthfill water supply dam was constructed for .Clarence valley Council in 2008. There have been ongoing problems with surface tunnel erosion on the downstream face of the dam requiring regular maintenance.


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DSC2F requires dam owners to develop and maintain operation and maintenance (O&M) manuals, based on organised programs and systematic inspections. The DSC maintains an active education program in this area and audits performance through the owners’ Surveillance Reports and by regular inspections of dams by DSC members and staff. O&M Manuals should be prepared by appropriately qualified and experienced personnel including specialists such as civil, mechanical, and electrical engineers as required by the type and complexity of the dam and its equipment. Owners of prescribed dams are to ensure that there are appropriately trained and experienced personnel available to operate and maintain their dams in accordance with their O&M Manuals. The DSC also places great emphasis on dam owners properly recording and documenting their dams’ O&M activities.

Typical maintenance issues that often need to be addressed by dam owners include removal of trees from embankments, maintaining a short uniform grass cover on the downstream slopes of earthfill dams, keeping spillways clear and maintaining adequate wave protection on the upstream slopes of embankments.

A very important aspect is the proper operation and reading of a dam’s instrumentation systems. Most of the large dams in NSW have various forms of instrumentation, the most common being seepage measurement, piezometers and external surveys. The DSC is therefore concerned to see that all instrumentation is read regularly and correctly recorded, as well as maintained, operated and analysed such that the resulting readings are as reliable and accurate as possible. In this way the instrumentation readings can be used to help determine the safety of a dam.

Another important issue is the operation of dams with gated spillways which was marked as a significant outcome of the floods at Wivenhoe Dam in Queensland in January 2011. As a result, the DSC issued a letter to all owners of such dams advising them to review their spillway flood handling procedures. The DSC issued similar letters in 2013 following the Oaky River Dam failure in NSW in February 2013. The DSC reviews gate reliability studies upon their submission by dam owners.

“Dams require care throughout their lives to keep them in a safe condition”

7.1.9. Dams Safety Emergency Management

The DSC’s primary objective is to protect the public from dambreak floods and other uncontrolled releases from dam storages during normal operations, flooding and at times of increased risk while construction work is underway. Therefore it requires dam owners to prepare Dam Safety Emergency Plans (DSEPs) for dams posing a risk to downstream residents (ie Significant and Higher Consequence Category dams). The DSC has produced its Guidance Sheet DSC2G Emergency Management for Dams to aid owners in the preparation of DSEPs. The DSC is working with dam owners to ensure that there is a current updated DSEP in place for each dam posing a risk to downstream residents. DSEPs cover monitoring procedures, actions to be taken by the owner's personnel, pertinent advice to emergency agencies, information concerning the nature of dambreak flooding and communication protocols. These plans take into account the general increase in security world-wide required for strategic assets such as dams. (In 2008 a dam was destroyed by terrorists in Sri Lanka, and more recently special security precautions have had to be taken at dams in Iraq). The DSC has also prepared Guidance Sheet DSC2H Dam Security to assist dam owners in this regard.

To enable the DSEPs to function effectively, the DSC Guidance Sheet DSC3G General Dam Safety Considerations requires that all High and Extreme Consequence Category dams have telemetered storage level recorders and where practical, alarms on the downstream seepage measurement weirs to give warning of potential non-flood related failures.

In the event of a dam emergency being reported to the DSC (compulsory for Amber and Red Alerts), the DSC has in place a policy document to guide staff and members on the correct procedures for handling such emergencies. Except in very unusual circumstances, the DSC normally will not provide dam owners with technical advice during emergencies. Such advice would normally be provided by the dam owners’ technical experts or specifically engaged consultants.

Responsibility for developing and maintaining flood plans in NSW rests with the State Emergency Service (SES). The DSC looks to dam owners to liaise with the SES in developing flood plans and DSEPs to protect residents against the impacts of major floods that pass through their dams, with a main focus on any potential dam failure. The value of these plans, even for dams that meet normal safety requirements, was demonstrated in 1999 with activation of the Lyell Dam DSEP. That DSEP activation facilitated the timely evacuation of campers after the unexpected failure of the dam’s inflatable spillway section. Further demonstration was also provided during the May 2009 Murwillumbah floods, with the timely evacuation of residents at Uki downstream of Clarrie Hall Dam. The DSC will continue to strongly encourage dam owners to test DSEPs regularly, particularly with regard to “sunny day” failure (i.e. from a non-flood induced mechanism), where failures could come with very little warning.


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Lithgow No.1 Dam. Lithgow Council is currently looking at converting the usage of their dam from acting as a retarding basin to having an additional use as a water storage dam In August 2015 a DSEP Red Alert was triggered at Jerrara Creek Dam, located in a rural catchment inland from Kiama. As a result of a severe storm, rising flood water in the storage had ironically discharged through an engineered wide slot in the embankment that was the main feature of the designed decommissioning works (and that were then well over halfway through the decommissioning construction program). Shortly after 9 am on 25th August 2015 the SES issued an evacuation order (i.e. a Red Alert) for residents downstream of the dam. The floodwaters were discharged appropriately and the storage level soon abated. From a dam safety perspective however, it is pertinent to note that the dam did not suffer any failure or even any partial failure. Inspections by experienced engineers during the afternoon of 25th August confirmed that the dam and the then current staged works had performed very well during the discharge event. The SES issued an All Clear Notice on 26th August. This incident highlights the importance of the DSC’s requirement for a specific construction phase DSEP to be in place during any dam upgrade or major remedial works and with such a construction DSEP to be clearly understood and rationally updated based on construction milestones.

After the clean-up works at the dam site, the decommissioning works were effectively completed about 2 months later. Following the completed decommissioning, the DSC later was also able to not only remove Jerrara Creek Dam from the highest risk dams status group, but was also able to de-prescribe the dam.

The SES has continued to prepare and update flood plans for communities downstream of various NSW dams during the year. An important aspect of flood planning is early and comprehensive public awareness campaigns to inform affected residents of the details of these flood emergency plans.

To mesh the responsibilities of dam owners and the SES, the DSC’s Emergency Management Sub-committee (EMSC) meets as necessary to review and monitor the procedures used by the agencies concerned. As a result, dam incident warning protocols have been implemented with all of the emergency agencies. The EMSC also provides a channel for information exchange between the DSC and the SES, giving the SES regular updates on the safety status of dams in NSW. One of the issues that have arisen is the timing of the alerts, as some dam owners have been concerned that some evacuations may have been occurring too early. The DSC is therefore encouraging dam owners, their DSEP consultants and the SES to carefully examine, develop and agree on specific alert level timing at individual dams and to look at other alert triggers than just storage levels (e.g. perhaps in conjunction with rates of storage rise).


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7.1.10. Flood Retarding and Detention Basins

Flood retarding basins can have great value in reducing urban flood magnitudes. Most are small, with embankments only a few metres high, but they are usually situated in densely populated areas with drainage channels and conduits of limited flow capacity downstream. However, there are some large structures. One very large structure is Loyalty Road Retarding Basin, upstream of Parramatta, which is formed by a roller compacted concrete dam 29m high.

During the short periods that these basins store water they act as dams, and their failure could be damaging to downstream areas. The DSC prescribes those basins that would pose a significant threat to downstream communities or the environment in the event of failure. The potential threat of retarding basins to a community can be as significant as that from a major dam, since houses are often located immediately downstream.

Because the embankments forming most basins are dry for long periods, their response to floods is the same as the “first-fill” of a dam’s life, a period known to be much more prone to dam failure. Accordingly, retarding basins need to be designed, constructed, maintained and monitored in accordance with good dam engineering practice.

Retarding basins traditionally have been treated as an element within an urban drainage scheme. For such schemes the focus has been on floods up to the 1 in 100 Annual Exceedance Probability (AEP) floods, which has been the typical design flood. In the past, few owners and stakeholders recognised that a greater flood could occur and would cause a sudden increase in discharge or, in the worst case, could fail the embankment and threaten lives downstream.

The community at risk generally does not appreciate the potential for larger floods to occur. Recent examples of events with a probability lower than a 1 in 100 AEP (and hence a size greater than such a design flood) were the storm events in Toowoomba (January 2011), Mudgee (February 2011), across eastern Australia in March 2012 and again in early 2013. The flood event which overtopped and failed Mannus Lake Dam near Tumbarumba in October 2010 (at that time a DSC prescribed dam of Low Flood Consequence Category) was estimated as likely about a 1 in 150 AEP event but possibly of a size up to a 1 in 300 AEP event.

In addition, there is also the risk of piping through basin embankments by flood waters seeping through cracks in the upper levels of embankments caused by drying out of the earthfill during the long dry periods between floods. The DSC has assisted in educating the community and key stakeholders of these dangers. These efforts are beginning to pay dividends in improved monitoring of the basins by their owners and the improved understanding and experience of engineering consultants.

ANCOLD is currently developing Guidelines on retarding basins, with one DSC member on the Working Group. It is anticipated that a first main draft of these Guidelines will be made available in late 2018. As there are several hundred basins in NSW, there is a strong possibility that some basins could be tested annually by an extreme storm. The DSC’s requirements aim to ensure that basins will withstand appropriately large floods, or that basin failure does not involve a significant risk to life. The design needs to allow for the effects of future development in the area and any possible “domino effect” of basin failure if there are multiple basins in a cascade arrangement. The DSC requires that prescribed retarding basins are subject to relevant procedures regarding surveillance, inspection, operation and maintenance but continues to be concerned with the poor maintenance some basins receive. Inspections still reveal basins with partially blocked outlets, which can significantly reduce the basin’s flood capacity. This reinforces the need for basins to be inspected at least monthly, as part of their maintenance schedule, as well as after significant flood events.

The DSC continues to maintain close liaison with basin owners during the design stage, particularly to oversight the designs and investigations of urban drainage designers whose experience of dams engineering is often limited to small structures. DSC staff carries out regular basin inspections and the DSC has a Guidance Sheet DSC3E Flood Retarding Basins to provide advice on retarding and detention basins.

Owners, or their consultants, should inform the DSC of proposals for new basins (or un-notified existing basins) so that the DSC can consider their need for prescription. The DSC prescribes all basins whose failure could cause loss of life. The DSC also requires assessment of the incremental consequences of failure of the basin. Owners of prescribed basins are also required to develop an appropriate DSEP in conjunction with the relevant emergency authorities.


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Diamond Circuit Detention Basin. This 3m high basin in Maitland was upgraded during in 2018 to improve its flood handling capability and protect downstream residents.

7.2. Regulation of Mining near Dams

7.2.1. Background

In NSW, legislation provides for the risks to dams, and their reservoirs, from mining to be independently assessed from a civil engineering perspective. Usually this is done under the Mining Act 1992, by the DSC advising the responsible Minister, but it may also be done directly by the DSC under the Dams Safety Act 1978. The DSC’s objective is to ensure that risks to dams, and their reservoirs, from mining are tolerable in terms of the community’s interests. The most common regulatory mechanism involves declaration of Notification Areas (NAs) around selected prescribed dams (see Prescribed Dams map). Mining within these areas requires Ministerial approval, acting on advice from the DSC, or the DSC may use its powers under the Dams Safety 2018/19 Overview

7.2.2. 2018/19 Overview

“During 2018/19 about 35 million tonnes of coal were extracted near prescribed dams in NSW” The mining projects considered by the DSC during the year were mainly for mining coal by underground or open-cut methods. Tonnages extracted around prescribed dams have remained around 30 million tonnes; however there has been a reduction in the number of applications in recent financial years reflecting a downturn in the market. 12 new applications were endorsed and another one was varied as below: Underground Mining Dendrobium (3), Integra (1), Metropolitan (4), Tomingley (1) Open Cut Mining Mt Arthur Nth (1), Mount Owen (1), Wambo (1), Walker Quarries (1)

During 2018/19, under the DSC's guidelines, about 35 million tonnes of coal were extracted from within Notification Areas around prescribed dams, without reducing safety of the dams or storages below tolerable levels. Summary details of these mining approvals are given in Tables 7.9 and 7.10. Prior to the formation of the DSC, some of these coal deposits would not have been mined due to the concerns of dam owners.


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7.2.3. Details of New Applications and Currently Monitored Mines

Ashton Underground Mine continued operations beside Ravensworth Void 5 Ash Dam.

Bengalla Mine continued open cut operations within three NAs around mine owned dams and adjoining mine dam.

Broula King Gold Mine provided monthly reports of dam monitoring while on care and maintenance.

Dendrobium Colliery continues extraction of a series of longwalls (currently mining Longwall 15 in Area 3B) adjacent to Avon Reservoir which supplies water to the Illawarra area.

Drayton Mine continues to conduct rehabilitation works within the Mt Arthur Notification Area and reporting on monitoring of the Liddell Ash Levee Dam.

Glennies Creek Colliery, having been purchased by Rixs Creek Colliery, continues to report on monitoring results for Camberwell TD2 and Possum Skin Dams.

Hera Gold Mine continues underground mining within the Hera NA around the Hera Tailings Storage Facility.

Integra Gold Mine commenced development of longwalls within the Mt Owen NA (neighbouring mine tails dam)

Mangoola Coal continues coal extraction by open cut methods adjacent to its own tailings dams and Raw Water Dam.

Maules Creek Coal continues extraction of coal from within the Maules Creek Notification Area.

Metropolitan Mine continues longwall coal extraction within the Woronora Notification Area without incident.

Mount Arthur Coal completed extracting coal within the NA of the Mt Arthur North Environmental Dam.

North Parkes Underground continues extracting gold within the North Parkes Notification Area by Block Caving methods. An open cut operation beside Rosedale Tailings dam is in the initial stages of production

Tomingley Gold Mine ceased open cut mining and commenced underground developments inside Notification Area.

Wambo Coal Mine commenced mining remnant strips of coal beneath North East Tailings dam by open cut methods.

Woodlawn Mine is hydraulically mining tailings and underground mining near its water dam,

7.2.4. Policies, Procedures and Organisational Updates

Resources employed during the year were reduced owing to the transitional stage with the new Dams Safety Bill 2015. However, no changes have been made to the existing policies as outlined in the Guidance Sheets listed in Table 7.8 and are available on-line on the DSC’s website. An internal system for checking compliance with mining conditions operates. This is used for workload management and for reminders to mining companies to deliver material on time

Table 7.8 – Guidance Sheets for Mining near Dams

Document Title Date

DSC4A Mining Near Prescribed Dams – Administrative Procedures March 2011

DSC4B Mining Near Prescribed Dams – Mining Applications June 2010

DSC4C Mining Near Prescribed Dams – Management and Monitoring Matters June 2010

DSC4D Mining Near Prescribed Dams – Contingency Plans June 2010


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7.2.5. Mining Statistics

Table 7.9 - Mining in Notification Areas Item 2015/16 2016/17 2017/18 2018/19

Coal Removed from Notification Areas (million tonnes) 28 28 26 35

Current Approvals: Actively Mining 31 15 19 16

Actively Monitoring 40 24 27 24

Applications Processed 7 12 8 12

Variations to Existing Approvals 6 4 8 1

Titles Processed 53 11 158 87

Provided comments on SMP / Part 3A applications 13 4 10 20

New Proposals Discussed 4 1 1 2

Table 7.10 - Monitored Approved Mining 2018/19 Possible Effect on

Approval Mine Dam Mining Type Active Mining

Dam Storage

Dam Structure

Currently Monitoring

Ashton - 5 Ashton Underground

Ravensworth Void 5 Ash Dam 1st Workings No No Yes Yes

Bengalla - 1 Bengalla Bengalla Staged Discharge Open-cut Yes No Yes Yes

Bengalla-2 Bengalla Bengalla CW1 Open-cut Yes No Yes Yes

Bengalla-3 Bengalla Mt Pleasant ED3 Open-cut Yes No Yes Yes

Broula King 1 Broula King Broula King Tails Open-cut No No Yes Yes

Dendrobium-1 to 3 Dendrobium Areas 1 & 2

Cordeaux & Upper Cordeaux #2 Longwall No Yes Yes Yes

Dendrobium-4 Dendrobium Area 3A Cordeaux Longwall No Yes Yes Yes

Dendrobium-5 to 12

Dendrobium Area 3B Avon Longwall Yes Yes No Yes

Drayton-2 Drayton Liddell Ash Dam Levee Open-cut No No Yes Yes

Glennies-5 Rixs Creek North

Camberwell TD2 & Possum Skin Open-cut No No Yes Yes

Hera-1 Hera Gold Hera TSF Underground Metal Mine Yes No Yes Yes

Integra-1 Integra Underground Mt Owen Tails (TP1) 1st workings Yes No Yes Yes

Mangoola-3 Mangoola Raw Water Dam & Tailings Dam Open-cut Yes No Yes Yes

Mangoola-4 Mangoola Pit Water Dam Open-cut Yes No Yes Yes

Mauls Creek-2 Maules Creek Maules Creek TSF Open-cut Yes No Yes Yes

Metropolitan-6 Metropolitan Woronora Reservoir 1st workings Yes Yes No Yes

Metropolitan-7&8 Metropolitan Woronora Reservoir Longwall Yes Yes No Yes

Mt. Arthur-1 Mt. Arthur Environmental Open-cut Yes No Yes Yes

Northparkes-2 Northparkes North Parkes TSFs Underground Block Caving Yes No Yes Yes

Northparkes-4 Northparkes North Parkes TSFs Open-cut Yes No Yes Yes

Tomingley-1&2 Tomingley OC Tomingley TSF Open-cut Yes No Yes Yes


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Table 7.10 - Monitored Approved Mining 2018/19 (continued) Possible Effect on

Approval Mine Dam Mining Type Active Mining

Dam Storage

Dam Structure

Currently Monitoring

7.3. Information Systems

2018/19 Overview

Various information technology support systems were maintained and updated. New features were added to the DSC Databases including the ability to track outstanding reports. The records were moved to electronic storage systems.

Work activities included the following:

� New DSC computers were leased via the Department.

� Significant work was carried out in terms of culling reports, scanning reports and archiving reports in preparation to move to another floor in the building.

� All Dams safety files have been created in electronic storage systems (HP Content Manager 9).

� The Prescribed Dams folders and DSEP’s were scanned and moved to the electronic storage systems due to limited physical storage in the current work area.

� Incoming/outgoing correspondence was processed and kept up to date in the databases. This included dealing with over 1,800 officially documented correspondence items.

� DSEP request letters were generated and sent to Dam Owners.

� Tailings Dams – Advisory letters were sent out to tailings dam owners � Electronic records, including GIS datasets, were captured and updated.

� Metadata information and reports were generated. � Surveillance Report request letters were generated and tracked.

� Dams Safety functional retention and disposal authority was created and approved by the Board of the State Archives and Records Authority of NSW in accordance with Section 21(3) of the Records Management Act

Wambo-8&9 Wambo North East Tailings Dam Open-cut Yes No Yes Yes

Woodlawn-1 Woodlawn Evaporation Dam Underground Yes No Yes Yes

Woodlawn-2 Woodlawn Tailings Dam Hydraulic Mining of Tailings

Yes No Yes Yes


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8. Stakeholders

8.1. Liaison with Stakeholders

8.1.1. Stakeholder Liaison Diagram

The DSC’s role in dam safety in NSW requires interaction with a wide range of stakeholders as summarised in the following diagram, Figure 8.1.

Figure 8.1 – Stakeholder Liaison Diagram

8.1.2. General

In line with modern principles of good regulation, the DSC has adopted a goal of a high degree of transparency and continues to work toward having all its safety policies accessible to all stakeholders, by their incorporation into the Guidance Sheets. These are all readily available and easily accessible on the DSC Internet site (www.damsafety.nsw.gov.au/DSC/infosheets.shtm). The DSC values a good working relationship with its key stakeholders, including affected communities, dam owners, mining companies and consultants. By this means the DSC can communicate its goals to engage co-operation in achieving dam safety. By understanding and recognising their responsibilities and liabilities, most dam owners and mining companies adopt a strong commitment to dam safety. The DSC maintains regular contacts with its key stakeholders to foster its dam safety roles and to give the DSC an opportunity to gauge their level of satisfaction. The DSC responds to specific public enquiries on relevant dam safety issues as they might arise.

The DSC provides its Annual Report to the Minister and to the NSW Parliament. The DSC provides the minutes of each of its regular meetings to the Minister and briefs the Minister’s office on any significant incident involving a prescribed dam, including for example any Red Alert that might be issued as part of a DSEP. In addition the DSC Executive meets periodically with the Minister and/or key ministerial staff members to discuss recent main issues as part of regular updating and liaison with government.

NSW Dams Safety Committee

NSW Parliament

and Government

Dam Owners outside NSW

NSW Public

DSC provides Annual Report. DSC updates and briefs Minister for Regional Water

DSC sets dam safety requirements & checks, provides information & assists training, liaises on

submissions and documentation

DSC sets mining requirements around dams & audits them

4. Resources and Energy (R&E) - Mining Regulation aspects 5. Dept. of Planning and Environment (DPE) - Involvement in mine planning 6. State Emergency Services (SES) - DSEPs and Emergency Mgt. Sub- Committee

Liaison & review - DSC inputs to ANCOLD Guidelines

Liaison - DSC provides information on dam safety matters

Liaison & review - DSC inputs to ICOLD Bulletins

NSW Departments and Agencies 1. Department. of Industry (the Dept.) - Finance, HR and IT System Services 2. Dept. of Primary Industries (DPI) DPI Water - Budget distribution/financial support - Liaison on Council/LWU dams 3. Auditor General (AG) - Undertakes annual audit of DSC finances

ANCOLD ICOLD

4. R&E 5. DPE 6. SES

1. Dept. 2. DPI 3. AG

NSW Mine Owners

NSW Dam Owners

Liaison & Information exchange


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8.1.3. Dam Owners

The DSC has a role to educate and inform dam owners on their responsibilities and on national and international standards, practices and technologies. It communicates its objectives and concerns to dam owners and their representatives through various avenues, such as seminars, presentations and its Internet site.

Close contact is maintained by the DSC with owners of prescribed dams through meetings held during the year to discuss specific dam requirements, general procedures, and to ensure owners are able to communicate their concerns to the DSC. For example, during 2018/19 the DSC inspected 37 prescribed dams and basins and held on-site meetings with owners’ personnel. DSC mining staff also inspected many mine sites and held on-site meetings with personnel from those mines.

The dam safety education of local government authorities, mining companies and private dam owners is of particular interest to the DSC, because their staffs do not usually have specialist engineering knowledge of dams. Education of these owners is assisted by regular site visits by the DSC and/or its staff to meet owners' representatives to discuss relevant issues. Such meetings are invaluable in reaching a common understanding of the problems facing these owners in regard to asset management and responsibilities to the community, and obtaining feedback for enhancing the DSC's education role. To this end, DSC members and staff had individual meetings during 2018/19 with a number of dam owners to discuss various dam related activities – i.e. upgrades, investigations, incidents and submissions (either actual or intended). Several other dams were discussed in detail during specific presentations made by owners and/or their consultants to the DSC.

At the DSC’s May 2018 meeting, Snowy Hydro Limited (SHL) personnel made a presentation on SHL’s dam safety management program, with emphasis on the safety reviews, risk assessments, investigations and the associated portfolio risk assessment (PRA) of its large dams. In addition, WaterNSW personnel updated the DSC on their recent review of practices following the failure of Oroville Dam spillway in 2017. This was very useful information for the Committee, and the DSC thanks SHL for the presentation and the supporting documents provided.

.

8.1.4. Dam Safety/Surveillance Training Courses

The DSC ran its first dam safety training course in 1991 with the assistance of the then Department of Public Works. Since then regular training courses for dam operators were set up and run by Public Works and later by the then Department of Water and Energy’s Water Utilities Performance (WUP) Dams Safety Management group with the assistance of DSC staff. Since 2009 following changes to the structure of WUP, and with a then new DSC Executive Engineer, the DSC has taken over the organisation and running of these courses of typically 3 or 4 days duration. The principal trainers for these courses are currently DSC member (and Surveillance Sub-committee Chair) Norm Himsley and Surveillance Engineer, Jason Porter, with assistance from Graham Hinds, recently retired from Water NSW.

Cowarra Creek Dam This 41m high embankment dam, owned by Hastings District Council was used for inspection purposes as part of a dam safety training course run by the DSC in May 2019


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During 2018/19 the DSC was involved in organising and running two types of dam safety training courses for NSW dam operators. Four day dam safety/surveillance courses for water dam operators and other dam staff were held at Port Macquarie in November 2018, February 2019 and May 2019 and a shorter 3-day course for mine dam personnel held at Port Stephens in March 2019. These four courses each attracted close to the fully subscribed 30 participants.

Over several years, the DSC trainers were very heavily involved in the development of the syllabus for a TAFE course that provides 5 dam units of competency within the Certificate III in the National Water Industry Operation Training Package NWPO7. This DSC initiative and development of an agreement with TAFE NSW (initially in 2013) provides a training course to give dam operators and other relevant dam personnel full accreditation through more detail and specific applicability of the course modules included. The Water Operators Certificate III Training package undertaken thus assists in the continuing educational development of the staff of particular dam owners that require such accreditation qualifications. To date the DSC have run four courses under its TAFE agreement. In addition during the year Norm Himsley updated his training credentials in line with TAFE requirements for all its teachers.

Since the inception of the standard training program a number of years ago and enhancement since then, these training courses have resulted in a noticeable improvement in the general standard of dam owners’ dam safety management. This training course work is seen as an important part of the DSC’s education role for dam owners. All 2017/18 training courses were well attended. Since 1991 about 1,800 operators in NSW have been trained or retrained in dam safety inspection, resulting in very notable improvements in the dam owners’ routine and other inspection regimes.

The increasing emphasis over a number of years by the DSC on owner education in NSW has been reflected in numerous requests from portfolio dam owners within and outside NSW for educational assistance in similar training courses for dam operators. In 2018/19 for example, the DSC provided principal training assistance for 3 other dam safety and surveillance courses, each of 2-3 days duration, for specific dam owners on an invitation basis – SunWater Limited (in Townsville and Mackay) and BHP (at one of its large mines in central QLD). Such involvement is of value to the DSC in broadening its experience of dam safety management issues, in benchmarking its own performance against the procedures and practices of similar authorities and assisting in maintaining currency through the feedback from the other authorities and also from the individual course participants. As a by-product and at effectively no cost, it also provides opportunities for inspections of some large interstate dams and discussions on common site management problems – and thus adding to the DSC’s collective detailed technical knowledge. “Since 1991 about 1,800 operators in NSW have been trained or retrained in dam safety inspection, resulting in very notable improvements in the dam owners’ routine and other inspection regimes.”

8.1.5. Other Australian States, ANCOLD and ICOLD Matters

Various DSC members and staff continue to be involved in Australian National Committee on Large Dams (ANCOLD) matters, through participation in ANCOLD Guidelines working groups (including Messrs Cooper, Himsley and Knight).

As also outlined in Section 8.2, in October 2018 several DSC members and the Executive Engineer attended the annual ANCOLD Conference in Melbourne, Victoria. The DSC also was represented by the Chair, another DSC member and the Executive Engineer at the state dam safety regulators’ annual meeting that was held in conjunction with the ANCOLD Conference. The lead-up to this regulators’ meeting involved some liaison and afterwards involved some further information exchange follow-ups amongst the other state regulators.

8.1.6. Other Liaison and Interaction with Stakeholders

During the year the DSC continued to foster its close relationship with the State Emergency Service (SES) through liaison activities associated with the DSC’s Emergency Management Sub-committee (EMSC) work. For example, the DSC provided the SES with an annual update of the prescribed dams list plus associated dam location coordinates. The DSC received in return from the SES the local government area (LGA) information for the prescribed dams – for updated data incorporation in the DSC’s database. The DSC also typically provides periodic updated information to the SES on the DSC’s highest risk dams and basins status group.

During 2018/19 the DSC continued to liaise with and respond to relevant other government agencies and sections by providing requested pertinent information.


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8.2. Education and Training of Members and Staff and Associated Matters

The DSC’s members and staff are required to have extensive and varied experience in dam engineering and mining. However, it is still essential in any organisation to keep abreast of modern developments in all the technical and societal fields related to its functions. This is particularly important in the case of the DSC, because of the diverse technical knowledge required from its staff. Accordingly, the DSC’s members and staff attended relevant conferences and courses during the year.

The DSC members kept their knowledge up-to-date through various professional technical activities external to the DSC. Various DSC members and staff continue to be involved in ANCOLD matters, through participation in ANCOLD Guidelines working groups (including Messrs Cooper and Himsley) and/or involvement in running ANCOLD short courses. Some DSC members are or have been involved in ICOLD committees and matters.

In October 2018 the DSC Chair Brian Cooper, DSC member Norm Himsley and Executive Engineer Chris Salkovic attended the 2018 ANCOLD Conference & Workshop on Dams in Melbourne, Victoria. Several other DSC members and Sub-Committee members also attended the ANCOLD Conference, courtesy of their employment organisations. They included George Samios, Samson Banzi and Michael Thornton. These annual ANCOLD Conferences provide valuable forums for exchange of information and updating on dam safety issues as well as providing the annual opportunity for dam safety regulators nationwide to meet and review pertinent issues. Messrs Cooper, Himsley, Samios and Salkovic also attended the ANCOLD annual general meeting (AGM) held immediately after the Conference, with Chris Salkovic, as the DSC Executive Engineer, having the responsibility of voting rights at the AGM for the DSC (an organisation member of ANCOLD).

On behalf of the DSC, Messrs Cooper, Himsley and Salkovic also attended the state dam safety regulators’ annual meeting held in conjunction with (and on the day immediately prior to) the ANCOLD Conference & Workshop – to discuss and update knowledge of actions undertaken by dam regulators across Australia during the year, various dam incidents and news of importance nationally and also likely upcoming developments in their various dam safety regulatory spheres. There were further information exchange follow-ups amongst the state regulators after the meeting.

In April 2019 ANCOLD held a 2-day Dam Operators Forum, based in Western Australia, with main organisational assistance provided by WA Water. Although no DSC staff attended this Forum, the DSC supported ANCOLD (at its request) through a group promotional email sent to a selected large group of dam owner representatives.

As well as its full organisation membership of ANCOLD, the DSC is also a member for journal and associated subscription purposes of the USA’s Association of State Dam Safety Officials (ASDSO), the Canadian Dam Association (CDA) and the New Zealand Society on Large Dams (NZSOLD).

All of the above mentioned points concerning ANCOLD, ICOLD and various overseas authorities have helped greatly to supply highly valuable information and networking on national and international dam safety practices.

Quite importantly, all these experiences and other direct significant information sources enable DSC members and staff to improve and update the DSC’s dam safety/surveillance practices and also attain greater understanding of latest national and international practices in dams engineering generally. The knowledge gained is very valuable to the DSC by assisting in further development of its policies, strategies and procedures.

The DSC’s expertise in monitoring mining activities near dams using a broad range of techniques continues to be internationally recognised, with international requests for information on DSC practices and procedures for regulating mining near stored waters.

As part of the DSC’s policy on staff development, which targets staff training and efficiency, staff attended a variety of in-house and relevant external training courses during the year.


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9. Administration and Human Resources DSC members are subject to the Department of Premier & Cabinet Conduct Guidelines and the DSC staff members are subject to the NSW Department of Industry Code of Conduct, which provides an ethical framework for decisions, actions and behaviour for all department and related employees. As an extension of those requirements, the DSC has established policies on Managing Conflicts of Interest, and on Interactions with Stakeholders and the Public. The DSC has a policy of Delegated Authority, with a Schedule of Delegations, to guide members and staff. The DSC has also developed a policy for handling media enquiries, including necessary synchronisation with the overall policy of Dept. of Industry.

The DSC rents office space at 10 Valentine Ave, Parramatta from the NSW government. In May 2017 the DSC moved office from the third floor to the eleventh floor of the building and has subsequently moved to another section of the eleventh floor in late 2017. The Department of Industry provides the DSC (under cost-effective reimbursement) with financial processing support, maintenance of the accounting system, the payment of invoices, provision of payroll service, receipting, and the provision of associated taxation services. The DSC had been granted general exemption from TPP09-05, Internal Audit and Risk Management Policy for the NSW Public Sector (see Section 10.4).

Several of the organisations that nominate members to the DSC continue to provide technical assistance in specialised areas and in-kind contributions and the DSC wishes to especially acknowledge their valuable assistance.

As part of the DSC's administrative alignment with DPI Water (part of the Dept. of Industry) the DSC's Government Information Public Access (GIPA) statistics are published in the relevant Annual Report for that area of the Department. There were no requests to the DSC for information under GIPA legislation during the year.

To ensure the maintenance of appropriate standards of Work Health and Safety (WHS) practices in the DSC, the DSC’s WHS practices, with necessary minor adaptations, now align with the Department’s WHS Policy and which in turn accords with the Work Health and Safety Act 2011. The DSC also has in place a policy on the WHS roles of its staff and members. In relation to WHS, there were no work injuries in 2018/19. DSC staff and some members also received various items of personal protective equipment, as necessary, for use in site and field inspections. Various staff who required them, acquired construction site “White Cards” via undertaking suitable accredited courses.

As part of its contracted administration assistance to the DSC, DPI Water implements the Department’s Employment Opportunity (EEO) and ethnic affairs policies for, and with, the DSC. The DSC is well aware of, and committed to, the associated principles of multiculturalism inherent within these policies. The DSC employs a very culturally and ethnically diverse group of male and female staff as part of the Departmental multicultural policies and services program. The DSC had 7 staff as at 30th June 2019. The staff mix includes 4 males and 3 females. Of these 7 staff, 4 people were born in Australia and the other 3 people were born overseas.

The DSC is progressively implementing the Government’s Waste Reduction and Purchasing Policy by implementing more electronic storage of information and use of recycled paper.

Port Macquarie Dam operators inspecting this 21m high earthen dam as part of the DSC’s dam operator training course held in Port Macquarie in February 2019


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10. Finance

10.1. Independent Auditor’s Report


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NSW dams Safety Committee Annual Report 2018 / 2019

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10.2 Audited Financial Statements


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10.3 Internal Audit and Risk Management Attestation for the 2018/19 Financial Year

The Dams Safety Committee (DSC) is funded predominantly from a NSW Treasury approved amount of grants & contributions via DPI Water which is within the Department of Primary Industries (DPI) and in turn the wider umbrella of the Department of Industry. The amount of annual grants & contributions is based on an approved budget calculated to allow the DSC to meet the cost of its operations as they are incurred. During 2016/17, DPI Water continued to provide general financial support to the DSC, including the budgetary distribution of grants & contributions and associated internal audit services.

In February 2013 the DSC’s Minister formally supported the DSC’s request for exemption from the Treasury Policy Paper TPP09-05, Internal Audit and Risk Management Policy for the NSW Public Sector (the Policy) on the basis that compliance with the Policy would impose costs and administrative burden not commensurate with the size and risk profile of the DSC. This exemption had been backed by the then NSW Department of Trade & Investment, the predecessor of the Department of Industry.

After an ensuing application to NSW Treasury by the DSC, in June 2013 Treasury granted the NSW Dams Safety Committee a general exemption from TPP09-05 and the requirement to attest to governance arrangements prescribed by the Policy. The exemption commenced in the 2012/13 financial year and is ongoing. The exemption therefore applied during the 2018/19 financial year.


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Appendix A – Dam Owner and Consequence Category Summary - 30 June 2019

Dam Owner Prescribed Dams Surveillance Reports received/reviewed 2018/19

DSC inspections 2018/19

Water Corporations (Government owned) (includes WaterNSW, Sydney Water, Hunter Water)

60 5 7

Snowy Hydro Ltd (part Govt. owned) and other Power Generating Companies 14 6 -

Local Government (Councils & Water Utilities) 154 32 8

Other NSW Government Authorities 11 3 3

Mining Companies (Water & Tailings Dams) 118 40 17

Private Owners 30 4 2

Others 3 - -

TOTAL 410 90 37

Notes: 1. The ownership of prescribed dams has been revised and updated, with the numbers of dams amended due to prescription

and de-prescription, and as a result differs from previous Annual Reports. 2. A total of 37 prescribed dams were inspected along with several non-prescribed dams (usually only done as part of

investigations for consideration of whether prescription might be required). Of the 410 prescribed dams and basins, the break-down by Consequence Category (CC) is as follows:

� Extreme CC = 32

� High CC = 182; comprising (2 still to be confirmed)

A. High A = 46

B. High B = 25

C. High C = 109

� Significant CC = 166

� Low & Very Low CC = 28 (Note: Generally prescribed if height >15m)

� To be categorised = 2

TOTAL = 410


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Appendix B – Current Prescribed Dams in NSW – 30 June 2019

Dam Map Ref Built Type Height (m)

Storage (ML) Owner

Abbotsbury Park Pond 2 F10 1970/2004 TE 6 18 Western Sydney Parklands Trust

Adelong Tailings Dam H8 - ER 14 280 Challenger Mines Pty Ltd

Aldridges Creek Dam* D11 1994 TE/ER 23 1,250 Consolidated Pastoral Company P/L

Antiene Lease Tailings Dam* E11 1999 TE/ER 35 10,000 Liddell Coal Operations Pty Ltd

Ashton Coal Clean Water Dam 1* E10 1985 TE 15 360 Ashton Coal Operations Pty Ltd

Avon Dam* G10 1927/71/95 PG/ ER 72 214,400 WaterNSW

Bagnalls Beach Road Basin E12 2002 TE 3.5 22 Port Stephens Council

Bakers Road Detention Basin C13 2010 TE 6.5 200 Coffs Harbour City Council

Bamarang Dam* G10 1983 TE 26 3,800 Shoalhaven City Council

Banks Rd Basin F10 1997 TE 3 60 Liverpool City Council

Barden Ridge Lower Dam* F10 2008 PG 22 36 Sutherland Shire Council

Barina Park Detention Basin [R] G10 1982 TE 7 5.4 Wollongong City Council

Bayswater Ash Dam* E10 1985 TE 39 22,000 AGL Macquarie Ltd

Bayswater Brine Decant Dam* E10 1986 TE 22 650 AGL Macquarie Ltd

Bayswater Cooling Makeup Dam* E10 1984 TE 11.5 460 AGL Macquarie Ltd

Bayswater Main Dam* E10 1979 TE 20 1,120 BHP Billiton

Beardy Waters Dam* B11 1932/60/87 VA 8.5 480 Glen Innes Severn Council

Beargamil Dam F8 1912/1924 TE 16 480 Parkes Shire Council

Ben Boyd Dam* J9 1978/82 TE 29 800 Bega Valley Shire Council

Bendeela Pondage* G10 1973 TE/ER 15 1,200 WaterNSW

Bengalla CW1 Dam * E10 2016 TE 13.5 900 Bengalla Mining Company

Bengalla DW1 Dam* E10 - TE 17.9 300 Bengalla Mining Company

Bengalla Stage Discharge Dam* E10 2000 TE 10 280 Bengalla Mining Company

Bennetts Road Detention Basin C13 2013 TE 7 160 Coffs Harbour City Council

Bingara Gorge Pond 1 G10 2011 TE 4.6 20.5 Lend Lease Communities (Wilton)

Blackbutt Reserve* G10 1957/95 TE 6 17 Shellharbour City Council

Blackwood Pit Tailings Storage Facility D1 - ER 10 2200 Broken Hill Operations Pty Ltd

Bloomfield U Cut Tailings Dam* E11 2010 TE 15 4,000 Bloomfield Collieries Pty Ltd

Blowering Dam* H8 1968/2011 TE/ER 114 1,631,400 WaterNSW

Boambee Newport Creeks Detention Basin - TE 7 340 Coffs Harbour city Council

Boorowa Dam* G8 1937, 1992 PG/TE 7 180 Hilltops Council

Bootawa Dam* D12 1968 TE 25 2,280 Midcoast Water

Borenore Creek Dam* F8 1928/43 VA 17 200 Cabonne Shire Council

Bosnjak Park US F10 1980 TE 1.9 22.5 Fairfield City Council

Bowra Dam* C12 2015 TE 22 4,500 Nambucca Shire Council

Brennans Creek Dam* G10 1976 DR 17 320 South32 - Illawarra Coal Pty Ltd

Brogo Dam* I9 1976 DR 43 8,980 WaterNSW


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Storage (ML) Owner

Brokers Road Retarding Basin* G10 1999 TE 7.5 70 Wollongong City Council

Brooklyn Retarding Basin* F11 1995 ER 4.8 3.7 Transport NSW

Broughton's Pass Weir* G10 1885 PG 6 50 WaterNSW

Broula King Gold Mine Tailings Dam 2^ F8 - TE/ER 18 25 Broula King Joint Venture Pty

Ltd

Bucklands Retarding Basin G10 1992 TE 5 2 Matt Crossingham

Bulga CHPP Dam*^ E11 2008 TE 14 3,000 Bulga Coal Management P/L

Bulga Mine Water Dam*^ E11 2016 TE 20 3,000 Bulga Coal Management P/L

Bulga North Inpit Tailings Storage E11 - TE 60 7000 Bulga Coal Management P/L

Bulga Northern Tailings Dam A E11 - TE 55 3400 Bulga Coal Management P/L

Bulga Old Tailings Dam*^ E11 1981 TE/Claylined 14 1,750 Bulga Coal Management P/L

Bundanoon Dam* G10 1959 VA 35 2,000 Wingecarribee Shire Council

Burrendong Dam* E9 1967/2011 TE/ER 76 1,190,000 WaterNSW

Burrinjuck Dam* H8 1928/57/94 PG 93 1,026,000 WaterNSW

Cadia Nth Waste Dump Detention Basin^ F8 2003 ER 18 50 Cadia Holdings Pty Ltd

Cadia South Tailings Storage Facility*^ F8 2001- TE/ER 69.5 75,000 Cadia Holdings Pty Ltd

Cadia Tailings Dam*^[R] F8 1997- TE/ER 82 93,000 Cadia Holdings Pty Ltd

Cadiangullong Dam*^ F8 1997 PG 43 4,200 Cadia Holdings Pty Ltd

Calala Raw Water Storage - TE 5.5 120 Tamworth Regional Council

Camberwell Tailings Dam 2* E11 1995/2004/2013 TE/ER 33 5,300 Bloomfield Collieries Pty Ltd

Cambewarra Dam G10 Pre 1930 TE 8.4 50 Shoalhaven City Council

Campbelltown Link Area Basin 1 G10 2004 TE 5.7 30 Campbelltown City Council

Campbelltown North Detention Basin G10 2000 TE 5.4 28 Campbelltown City Council

Captains Flat Dam* H9 1939/95 PG 16 820 Queanbeyan-Palerang Regional Council

Carcoar Dam* F9 1970 VA 52 35,800 WaterNSW

Carrington in-pit Tailings Storage Facility* E10 - TE 20 14,700 Rio Tinto Coal Australia Pty Ltd

Cascade Dam 1*^ F10 1905/15 VA 15 159 WaterNSW

Cascade Dam 2*^ F10 1926 TE 26 318 WaterNSW

Cascade Dam 3*^ F10 1938 TE 30 1,700 WaterNSW

Cataract Dam* G10 1907/1987 PG 56 94,300 WaterNSW

Cecil Hills Basin 100 F10 2001 TE 2.6 29 Liverpool City Council

Cecil Park Basin 3A* F10 1952/2007 TE 6.1 310 Liverpool City Council

Cecil Park Basin 3B F10 2014 TE 7.2 250 Liverpool City Council

Centennial Pk Res No. 1* F11 1899/92 PG 7 81 Sydney Water Corporation

Centennial Pk Res No. 2* F11 1925 PG/ TE 10 89 Sydney Water Corporation

Chaffey Dam*^ D11 1979/2004/11/16 TE/ ER 56 62,000 WaterNSW

Chichester Dam* E11 1923/84/94/2003 PG 44 22,000 Hunter Water Corporation Ltd

Chifley Dam* F9 1957/2001 TE 35 31,000 Bathurst Regional Council


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Storage (ML) Owner

Chinamans Dam G8 Pre 2012 TE 4.5 65 Hilltops Council

Clarrie Hall Dam* A13 1983/2014 DR 43 16,000 Tweed Shire Council

Clear Paddock Creek Basin C F11 2004/09 TE 5.2 82 Fairfield City Council

Clear Paddock Creek Basin W2 F10 2009 PG 3.3 60 Fairfield City Council

Clear Paddock Creek Basin W3 F10 2004/09 TE 2.6 47 Fairfield City Council

Coalcliff Dam* G10 1971/98 TE 9 97 Illawarra Coke Company

Cochrane Dam* I9 1958 TE 29 4,320 Cochrane Dam Pty Ltd

Colongra Creek Ash Dam* F11 1965 TE 5.7 5,500 Delta Electricity

Comberton Grange Ret. Basin G10 1991 TE 15 65 Shaolin Temple Foundation (Aust) Ltd

Comin Place Detention Basin F10 2000 TE 4.5 20 Fairfield City Council

Company Dam* F8 1867/2005 TE 5 95 Weddin Shire Council

Connors Creek Dam C10 1934 VA 9 360 Tamworth Regional Council

Copeton Dam* B10 1976/2012 TE/ ER 113 1,365,000 WaterNSW

Cordeaux Dam* G10 1926/77/88 PG 57 94,000 WaterNSW

Corindi Stage 3 Dam B13 - TE 9 900 Vitalharvest Ltd

Cowal Integrated Waste Landform F7 - TE 33.5 62,600 Evolution Mining Pty Ltd

Cowal Gold Mine Reservoir D9 F7 2007 TE 7 800 Evolution Mining Pty Ltd

Cowal Northern Tailings Dam* F7 2005/09 TE 18.2 19700 Evolution Mining Pty Ltd

Cowal Southern Tailings Dam* F7 2007 TE 18.4 19,300 Evolution Mining Pty Ltd

Cowarra Dam* D12 2002 TE 41 10,000 Port Macquarie Hastings Council

Cowarra Creek Tailings Dam* H9 1986/11 ER 23 52 NSW Department of Industry, Crown Lands

Crookwell Dam* G9 1937 PG/VA 15 450 Upper Lachlan Shire Council

CSA South Tailings Dam*^ D5 1960/71/07/14 TE 16 6,000 CSA Mine - Glencore

CSIRO Retarding Basin F10 1993/2003 TE 6 124 Cumberland City Council

Cumnock Tailings Storage Facility E10 2013 ER 10 1,500 Ravensworth Operations Pty Ltd

Cumnock Tailings Storage Facility No. 3* E10 - TE 7 2,500 Ravensworth Operations Pty Ltd

Danjera Dam* G10 1971 CB/ER 30 7,800 Shoalhaven City Council

Dargues Reef Gold Project Tailings Dam* H9 - TE 30 640 Big Island Mining Pty Ltd

Dartbrook Mine Water Dam* E10 2000/06 TE 11 450 Anglo Coal (Dartbrook Mgt) Pty Ltd

Daruk Park Retarding Basin F10 1987 TE 2.5 48 Liverpool City Council

Deep Creek Snowy Dam I8 1961 PG 21 8 Snowy Hydro Limited

Deep Creek Dam* H10 1984 TE 32 4,900 Eurobodalla Shire Council

Delegate Flood Retarding Basin* J8 1985 TE 5 200 Snowy Monaro Regional Council - Bombala Branch

DEP Retarding Basin F10 1993/2005 TE 9.5 250 Blacktown City Council

Diamond Circuit Detention Basin^ E11 2005 TE 2.7 5.01 Maitland City Council

Dobinson Retarding Basin G10 - TE 8 3 Roads and Maritime Services

Dover Heights Reservoir* F11 1928 PG/ TE 8 85 Sydney Water Corporation

Drayton Water Supply Dam* E10 1980 TE 13 780 Drayton Coal (Drayton Mgt) Pty


ANNUAL REPORT 69


Storage (ML) Owner

Ltd

Dumaresq Dam* [R] C11 1896 PG 12 380 Armidale Regional Council

Dungowan Dam* D11 1957/1992 TE 31 6,300 Tamworth Regional Council

Duralie Coal Auxiliary Dam No. 1* E11 2009 TE 20 500 Duralie Coal Pty Ltd

Duralie Coal Auxiliary Dam No. 2* E11 2011 TE 30 2,900 Duralie Coal Pty Ltd

Duralie Coal Mine Water Dam* E11 2003 TE 18 1,405 Duralie Coal Pty Ltd

East West Road Dam C12 - TE 6 61 Roads & Maritime Services

Edgewood Detention Basin G10 2002 TE 4.8 19.2 Wollongong City Council

Edgeworth Detention Basin E11 - TE 2.6 12 Lake Macquarie City Council

Edmondson Park Basin 12 F10 2013 TE 3.9 48 Liverpool City Council

Elanora Country Club Main Dam F11 2002 TE 10 80 Elanora Country Club

El Klaros Dam E11 1993 TE 20 200 Mawipalivier Pty. Limited

Elura Tailings Dam^ E11 1997 TE 8 19,000 Endeavor Operations Pty Ltd

Emerson Street Reserve F10 2015 TE 2.75 13.4 Fairfield City Council

Emigrant Creek Dam* A13 1968/2002 TE/ PG 13 820 Rous County Council

Emma James Basin A13 - TE 3.6 14 Central Coast Council

Epping West Park Basin F11 - TE 1.15 1.8 City of Parramatta

Eraring Ash Dam* F11 1982 TE 25 21,000 Origin Energy

Eraring Attemperating Cooling Water Dam* F11 2010 TE 32 820 Origin Energy

Eucumbene Dam* I8 1958/78 TE/ ER 116 4,800,000 Snowy Hydro Limited

Eurobodalla Southern Storage I10 - TE 35 3000 Eurobodalla Shire Council

Fairfield Golf Course Basin [R] F10 Prior to 1980s TE 2.1 152 Fairfield City Council

Fitzroy Falls Dam* [R] G10 1974 TE/ ER 14 23,500 WaterNSW

Floraville Road Det. Basin^ [R] F11 1992 TE 4 20 Lake Macquarie City Council

Foothills Estate Ret. Basin 1 G10 1995 TE 7 21 Wollongong City Council

Foothills Estate Ret. Basin 3 G10 1995 TE 7.8 21 Wollongong City Council

Foothills Rd Basin G10 1979/95 TE 4 17 Wollongong City Council

Fountaindale Dam* G10 1915 VA 15 18 Kiama Municipal Council

Fox Hills Retarding Basin F10 1990 TE 3.3 230 Blacktown City Council

Freislichs Dam D1 1976 TE 13 230 University of New South Wales

Gannet Place Retarding Basin G10 1993 TE 5 5 Wollongong City Council

Garden Suburb Det. Basin No. 2 E11 2000 TE 9 14 Lake Macquarie City Council

Geehi Dam* I8 1966 ER 91 211,000 Snowy Hydro Limited

George Bass Drive Det. Basin H10 1990/08 TE 2.5 10 Eurobodalla Shire Council

Georgia Terrace Detention Basin F10 - TE 4 2 The Hills Shire Council

Glenbawn Dam* E10 1958/87 TE/ER 100 750,000 WaterNSW

Glenmore Park Retarding Basin 4 F10 1997 TE 5.5 270 Penrith City Council

Glennies Creek Dam* E11 1980-83 DR 67 283,000 WaterNSW

Glenquarry Cut Control Structure* G10 1974 PG 18 24,100 WaterNSW

Gooden Reserve Det. Basin F10 1997 PG 5 380 The Hills Shire Council

Googong Dam* H9 1977/92/2010 ER 66 124,000 Icon Water Limited


70 ANNUAL REPORT


Storage (ML) Owner

Gosling Creek Dam* [R] F9 1890 PG 8 650 Orange City Council

Grahamstown Dam* E11 1964/96/01/05 TE 15 185,000 Hunter Water Corporation Ltd

Greaves Creek Dam* F10 1942 VA 19 310 WaterNSW

Green Meadows Retarding Basin G10 1981/93/03 TE 5.4 120 Shellharbour City Council

Greenway Drive Retarding Basin 10 A-B F10 1995/96 TE 4.5 132 Liverpool City Council

Gunyah Park Basin G10 1993 TE 4 4.5 Wollongong City Council

Guthega Dam* I8 1955 PG 34 1,830 Snowy Hydro Limited

Hamilton Valley Retarding Basin 5B I6 1995 TE 3.3 130 Albury City Council

Hamilton Valley Retention Basin 5A I6 1995/09 TE 4.8 164 Albury City Council

Hera Tailings Dam* C6 2014 TE 9 1700 Aurelia Metals Ltd

Hillgrove Eleanora Dam* C11 1980 TE/ER 10 68 Hillgrove Mines Pty Ltd

Hillgrove Tailings Dam No. 1* C11 1982 TE/ER 45 1,200 Hillgrove Mines Pty Ltd

Hillgrove Tailings Dam No. 2* C11 2007 TE/ER 15 280 Hillgrove Mines Pty Ltd

Honeysuckle Creek Dam F11 1984/91 PG 9.3 12 Killara Golf Club Ltd

Horningsea Park Det. Basin G10 2011 TE 3.5 36 Liverpool City Council

Houston Dam E10 - TE 2.0 2275 Anglo American Metallurgical Coal

Hoxton Park Basin 6 F11 2012 TE 5.7 142 Liverpool City Council

Hume Dam* I7 1936/67

/87/2003/11 /2013

PG/TE 51 3,050,000 Murray-Darling Basin Authority

Humphries Creek Tailings Dam* A12 1989 TE/ ER 17 1,100 White Rock Minerals Ltd

Humphries Creek Dam* A12 1989 TE 15 680 White Rock Minerals Ltd

Hungerford Hill Dam* E11 1970 TE 7 300 Roche Group

Hunter Valley Operations Lake James* E11 2010 TE 8 715 Rio Tinto Coal Australia Pty Ltd

Imperial Lake Dam* [R] D1 1967 TE 8.2 700 Essential Water

Island Bend Dam I8 1965/2001 PG 49 3,020 Snowy Hydro Limited

Jindabyne Dam* I8 1967/2008/2014 ER 72 690,000 Snowy Hydro Limited

Jordan Springs Village Lake F10 2013 TE 5 55 Maryland Development Company Ltd

Jounama Dam* H8 1966/68 TE/ER 44 555 Snowy Hydro Limited

Junction Reefs Dam* F8 1898 MB 19 2,500 Department of Industry, Crown Lands

Kalingo Dam* E11 1920/2012 TE 9 110 Austar Coal Mine Pty Ltd

Kanahooka Retention Basin G10 1993 TE 1.5 20 Forest Grove Community Association

Kangaroo Pipeline Control Structure* G10 1975 ER/PG 19 24,000 WaterNSW

Karangi Dam* C13 1980/96 TE/ER 38 5,600 Coffs Harbour City Council

Keepit Dam*^ C10 1960/2011 PG/ TE 55 424,000 WaterNSW

Kensington Centennial Park Pond. F11 1966 TE 2.3 150 Transport for NSW

Kentucky Creek Dam* C11 1942/84 PG 12 500 Uralla Shire Council


ANNUAL REPORT 71


Storage (ML) Owner

Khancoban Dam* I8 1966 TE 18 21,500 Snowy Hydro Limited

Killara Reservoir* F11 1930/95 PG/ TE 11 166 Sydney Water Corporation

King Park Basin [R] F10 - TE 1.7 102.5 Fairfield City Council

Knight Park F10 - TE 3.4 2.2 Fairfield City Council

Korrumbyn Creek A13 1918 VA 14 27 Tweed Shire Council

Lake Canobolas* F9 1918 VA/PG 13 450 Orange City Council

Lake Endeavour* F8 1940/2016 TE 21 2,400 Parkes Shire Council

Lake Ettamogah Winter Storage* H6 1994 TE 13 2,100 Norske-Skog Paper Mills (Aust) Ltd

Lake Inverell* B11 1940/45 PG 11 1,500 Inverell Shire Council

Lake Medlow*^ F10 1907 VA 20 300 WaterNSW

Lake Parramatta*^ F11 1857/98 MB/VA 15 590 City of Parramatta

Lake Rowlands* F9 1954 CB/TE 20 4,000 Central Tablelands Water

Leewood Ponds* C9 2014- TE 5 800 Santos Ltd

Lemington Mine Tailings Dam E10 1991 TE/ ER 8 1,000 Coal & Allied Operations Pty Ltd

Lidcombe Basin No. 6 F11 2003 TE 3.6 11 Cumberland Council

Liddell Ash Disposal Dam* E10 1971/82/13 TE 41 28,500 AGL Macquarie Ltd

Liddell Ash Levee* E10 1988/2003/12 TE/ER 16 29,000 Malabar Coal (Drayton Mngmt) Pty Ltd

Liddell Cooling Water Dam* E10 1968 TE 44 150,000 AGL Macquarie Ltd

Liddell Water Supply Dam* E10 1970 TE 31 4,500 AGL Macquarie Ltd

Lithgow Dam No. 2* F10 1907/14 VA 26 440 Lithgow City Council

Lithgow Dam No. 1 F10 1896/14 VA 12 77 Lithgow City Council

Lostock Dam* E11 1969-71 TE/ ER 38 20,000 WaterNSW

Loyalty Road Retarding Basin F11 1996 PG 30 1,500 Local Land Services, Greater Sydney

Lyell Dam* F10 1983/96 ER 50 34,000 EnergyAustralia NSW Pty Ltd

MacDonalds Dam TE 6 26 BHP - Mt Arthur Coal

Malpas Dam* C11 1968 TE/ ER 31 12,300 Armidale Regional Council

Mangoola Coal Raw Water Dam*^ E10 2010 TE/ER 26 2,000 Mangoola Coal Pty Limited

Mangoola Pit Water dam*^ E10 2010 TE/ ER 12 1700 Mangoola Coal Pty Limited

Mangoola Start-Up tailings dam*^ E10 2011 ER 35 3,900 Mangoola Coal Pty Limited

Mangrove Creek Dam* F11 1982 DR 80 190,000 Central Coast Council

Manly Dam* F11 1892/1922/84 PG 20 2,000 Sydney Water Corporation

Mannering Creek Ash Dam* F11 1963 TE 11 38,000 Delta Electricity

Mardi Dam* F11 1962/91/2011 TE 25 7,300 Central Coast Council

Maroubra Reservoir* F11 1966 PG/ TE 12 128 Sydney Water Corporation

Marrickville Oval Retarding Basin F11 1997 TE 1.8 27 Inner West Council

Maules Creek Mine - MWD2* C10 2015 TE 9 400 Maules Creek Coal Pty Ltd

Maules Creek Mine - RWD2* C10 2015 TE 6 200 Maules Creek Coal Pty Ltd

McCoy Park Retarding Basin F11 1987/2005 TE 5.5 450 City of Parramatta

McKinnons Gold Mine Tailings Dam D5 1996 ER 20 4,000 Redbank Mines


72 ANNUAL REPORT


Storage (ML) Owner

Medway Dam* G10 1964 VA 25 1,300 Wingecarribee Shire Council

Menindee Lakes Storage* E2 1960 TE 15 2,270,000 WaterNSW

Mimosa Road Basin [R] F10 - TE 1.7 40 Fairfield City Council

Mineral Hill Southern Tailings Dam* E6 2012 TE 20 1750 KBL Mining Ltd

Mineral Hill Tailings Dam* E6 1989 TE 24 1928 KBL Mining Ltd

Minmi Road Detention Basin ^ E11 1986 TE 4 46 City of Newcastle

Molong Creek Dam* F9 1986 PG 16 1,000 Cabonne Shire Council

Montrose Dam E10 - TE 18 900 Wambo Coal Mine; Peabody Energy Australia

Mooney Upper Dam* F11 1961 VA 28 4,600 Central Coast Council

Moore Creek Dam* C10 1898/2007 VA 19 220 NSW Department of Industry - Lands

Mount Owen North Void Tailings Dam*^ E10 1998/2008 TE/ ER 14 2,500 Glencore Mt Owen Pty Limited

Mount Owen Rail Loop Tailings Dam*^ E10 2003 TE 11.7 5,000 Glencore Mt Owen Pty Limited

Mount Pleasant Environmental Dam 3 E10 2018 TE 14 240 MACH Energy Australia p/l

Mount Pleasant MWD E10 - TE 19 2000 MACH Energy Australia p/l

Mount Pleasant Tailings Dam E10 - TE 32.6 3280 MACH Energy Australia p/l

Mount View Detention Basin E10 1983/2000 TE 5.7 250 Cessnock City Council

Mt Annan Wetland Dam No 1* E11 2006 TE 7 76 Camden City Council

Mt Arthur North Environmental Dam* E11 2002 TE 17 1,250 BHP Billiton – Mt Arthur Coal

Mt Arthur Tailings Storage Facility* E11 2013- ER 90 112,000 BHP Billiton – Mt Arthur Coal

Mt Boppy Gold Mine Tailings Dam* D5 - DR 19 900 Polymetals (Mt Boppy) P/L

Mt Thorley Abbey Green South TSF*^ F11 2007 ER 10 5,800 Rio Tinto Coal Australia Pty Ltd

Mt Thorley Central Ramp Tailings Dam* F11 1993/2001 ER 70 3,500 Rio Tinto Coal Australia Pty Ltd

Mt Thorley South Out Of Pit Water* D10 2011 TE/ER 20 2100 Rio Tinto Coal Australia Pty Ltd

Muirfield Golf Club F11 1969/85/2013 TE 7 19 Muirfield Golf Club Limited

Muirfield Golf Course Detention Basin F11 1969/93 TE 4 12 City of Parramatta

Murray 2 Dam I8 1968 VA 43 1,800 Snowy Hydro Limited

Murrurundi Dam* D10 1984 TE 10.4 180 Upper Hunter Shire Council

Narrabri Coal Rail Loop Dams 2010 TE 8.2 220 Narrabri Coal Operations

Narranbulla Dam G9 1966 TE 7.3 1,450 Narambulla Partnerships

Nepean Dam* [R] G10 1935/47/92 PG 82 70,000 WaterNSW

Newstan Southern REA Main Tailings Dam* E11 2007 TE 33 5,200 Centennial Newstan

Nixon Dam C10 1971 TE 16 220 J. Nixon

Norbrik Detention Pond F10 2010 TE 4 16 Aveo Southern Gateway p/l

North Turramurra Golf Course F11 2004 TE 4 12 Ku-ring-gai Council

Northmead Reserve Det. Basin F10 1983 TE 6 30 City of Parramatta


ANNUAL REPORT 73


Storage (ML) Owner

Northparkes E27 - Estcourt Tailings Dam* E8 2012 TE/ER 20 34,000 Northparkes Mines

Northparkes Infill Tailings Storage Facility E8 2017 TE and

ER 7 1900 Northparkes Mines

Northparkes Rosedale Tailings Storage Facility* E8 2016 TE 27 51,000 Northparkes Mines

Northparkes Tailings Dam* E8 1993/94/2009 TE/ER 27 3,900 Northparkes Mines

Northparkes Tailings Dam 2* E8 1996 TE/ER 25 3,900 Northparkes Mines

Nyngan Evaporation Pond * D6 - TE 5 450 EMC Metals Australia Pty Ltd

Nyngan Tailings Storage Facility* D6 - TE 10 800 EMC Metals Australia Pty Ltd

Nyrang Park RB 1992 TE 4 20 Wollongong City Council

Oak Flats Reservoir* G10 1978 TE 11 56 Sydney Water Corporation

Oaky River C12 1956 PG/ ER 18 2,700 Essential Energy

Oberon Dam* F9 1946/57/96 CB 35 45,000 WaterNSW

Old Quipolly Dam D10 1932 VA 19 850 Liverpool Plains Shire Council

Orange Research Station^ F9 1993/97 TE 6.1 200 NSW Department of Industry

Palm Tree Grove Ret. Basin [R] F11 1976/90 TE/ER 4 3 Gosford City Council

Parnells Creek Mine Water Dam E10 1993/2002 TE 8 800 Rio Tinto Coal Australia

Peak Gold Mine Tailings Dam*^ D5 1991- TE/ER 5.5 300 Peak Gold Mines

Pecan Close Retarding Basin F11 1998/03 TE 5 100 Gosford City Council

Pejar Dam* G9 1979 TE/ ER 23 9,000 Goulburn Mulwaree Council

Petrochilos Dam* A12 1969/06 TE 13.3 55 Kyogle Council

Pied Piper playground Det. Basin F11 2010 TE 4 5 Blacktown City Council

Pindari Dam* B11 1969/95 DR 85 312,000 WaterNSW

Pine Trees Detention Basin Off Map - TE 1.6 25 Lord Howe Island Board

Plashett Dam* E10 1987 TE 46 65,000 AGL Macquarie Ltd

Port Macquarie Dam* D12 1979 TE 19 2,500 Port Macquarie - Hastings Council

Porters Creek Dam* H10 1968 PG/TE 17 1,900 Shoalhaven City Council

Possum Skin Dam* C11 2004 TE 13.5 1,300 Bloomfield Collieries Pty Ltd

Potts Hill Res. 2* F11 1923/2000 PG/TE 5 570 Sydney Water Corporation

Prospect Dam* F10 1888/79/97 TE 26 50,200 WaterNSW

Puddledock Creek Dam* C11 1928 VA 19 700 Armidale Regional Council

Pymble Golf Course Dam F11 - TE 5.5 30 Pymble Golf Course

Quipolly Dam* D10 1955/2012 TE 21 5,400 Liverpool Plains Shire Council

Ravensworth Inpit Storage Dam* E11 1994 TE 13 1,000 Ravensworth Operations Pty Ltd

Ravensworth South Tailings Dam* F10 2008 TE 48 9,000 Ravensworth Operations Pty Ltd

Ravensworth Void 4 East Tails - Saddle Dam* E11 2007/09 TE/ER 10 5,000 Ashton Coal Operations Ltd

Ravensworth Void 5 Ash Dam* E11 2013 TBA 70 12,000 AGL Macquarie Ltd

Redbank Creek Dam* E9 1899/2011 VA 16 180 Mid-Western Regional Council

Redbank Dam 13^ F10 Unknown TE 7 15 North Richmond Joint Venture Pty Ltd

Redbank Dam 14^ F10 Unknown TE 7.7 40 North Richmond Joint Venture Pty Ltd

Riverview Void In-pit Water Storage* E11 2013 ER 65 6750 RTCA Hunter Valley Operations


74 ANNUAL REPORT


Storage (ML) Owner

Rocky Creek Dam* A13 1953/2010 ER 28 14,000 Rous County Council

Rouse Hill Ret. Basin 13^ F10 1994 TE 4.5 90 Sydney Water Corporation

Rouse Hill Ret. Basin 16 AB^ F10 2000 TE 4 17 Sydney Water Corporation

Rouse Hill Ret. Basin 5^ F10 1994/95 TE 4.6 140 Sydney Water Corporation

Rouse Hill Retarding Basin 9^ F10 1994 TE 4.9 46 Sydney Water Corporation

Rouse Hill Retarding Basin 9B^ F10 2000 TE 8 90 Sydney Water Corporation

Rushforth Road 100ML Reservoir B12 1985 TE 8.5 100 Clarence Valley Council

Rydal Dam* F10 1957/94 TE 16 370 WaterNSW

Rylstone Dam* E9 1954/03 VA 15 3,300 Mid-Western Regional Council

Sarah Fahey Park Retarding Basin F11 - TE 3.5 5 Central Coast Council

Sawyers Swamp Creek Ash Dam* F10 1979 TE 40 8,500 EnergyAustralia NSW Pty Ltd

Schofields North Rail Facility F10 - TE 2 10 Transport for NSW

Schofields South Rail Facility F10 - TE 2 6 Transport for NSW

School House Creek Basin F10 1989 TE 7 65 Penrith City Council

SE Tailings Storage Dam* E10 2002- TE/ ER 30 1,200 RTCA Hunter Valley Operations

Shannon Creek Dam B12 2008 TE 51 30,000 Clarence Valley Council

Shellcove Estate Detention Basin 1 G10 2005 TE 5 24 Shellharbour City Council

Shellharbour City Centre Basin G10 2001 TE 5 41.5 Shellharbour City Council

Sierra Place Detention Basin G10 1989/2001 TE/ ER 8.4 440 The Hills Shire Council

Site D Tailings Dam* E1 1996/2009/2015 TE 15 3,000 Perilya Broken Hill Limited

Smiths Creek Ret Basin 1 G10 2001 TE 8.8 70 Campbelltown City Council

Smiths Creek Ret Basin 2 C10 1996 TE 7.9 50 Campbelltown City Council

Smiths Creek Ret Basin 3 F10 1996 TE 6.4 32 Campbelltown City Council

Sooley Dam* G9 1930/61 /2005/11 PG 20 6,300 Goulburn Mulwaree Council

South Bulli Basin 1 G10 - ER 6 50 Allied Coal Pty Ltd

South Bulli Stormwater Dam G10 1992 TE 9 60 Wollongong Coal Pty Ltd

Spagnolos Road Detention Basin* C13 2015 TE 5.5 200 Coffs Harbour City Council

Split Rock Dam* C10 1988/2012 DR 66 397,000 WaterNSW

Spring Creek Dam* F9 1931/47/69 TE/VA 20 4,700 Orange City Council

Springvale Reject Emplacement Area* F10 2018 TE 15 1700 Springvale Coal Services

St Josephs School Ret. Basin G10 1990/2001 TE 5 16 Shellharbour City Council

St Peters Basin - 9SWB01 F11 - TE 5.5 14 Sydney Motorway Company

Stephens Creek Dam* D1 1892/1909 TE 15 20,000 Essential Water

Steuart McIntyre Dam* D12 2000 TE 24 2,500 Kempsey Shire Council

Stockdale Basin [R] F10 - TE 1.6 31 Fairfield City Council

Stockton Borehole Tailings Dam* E11 1982/1985 TE/ ER 18 5,000 Macquarie Coal Joint Venture

Suma Park Dam* ^ F9 1962/2016 VA 31 18,000 Orange City Council

Sunrise Mine TSF Cell 2 - TE 30 20000 Clean TeQ Sunrise Pty Ltd

Sunrise Mine Water Storage Dam - TE 8.3 1800 Clean TeQ Sunrise Pty Ltd

Talbingo Dam* H8 1970 ER 162 921,000 Snowy Hydro Limited


ANNUAL REPORT 75


Storage (ML) Owner

Tallong Railway Dam* G10 1883/1917/75 MB 5 70 John Holland Rail

Tallowa Dam* G10 1976 PG 43 90,000 WaterNSW

Tantangra Dam* H8 1960 PG 45 250,000 Snowy Hydro Limited

Tarrawonga Clean Water Dam C10 - TE 4.5 125 Whitehaven Coal Limited

Tenterfield Creek Dam B12 1930/74 PG 15 1,200 Tenterfield Shire Council

The Cove Dam* F11 1972 TE 7 140 World Village Trust

The Gables Lake and Basin F10 - TE 4.9 290 Celestino Pty Ltd

Thompsons Creek Dam* F9 1992 TE/ ER 54 28,000 EnergyAustralia NSW Pty Ltd

Thornleigh Reservoir* F11 1971 ER 14.3 400 Sydney Water Corporation

Tilba Dam* I10 1970/94/97 /2003 TE 18 140 Bega Valley Shire Council

Timor Dam* D9 1962 VA 19.5 1,100 Warrumbungle Shire Council

Tomingley Residue Storage Facility* E8 2013 ER 15 133 Alkane Resources Ltd

Tooma Dam* I8 1961 TE 67 28,000 Snowy Hydro Limited

Toonumbar Dam* A12 1971 TE/ ER 44 11,000 WaterNSW

Tritton Tailings Dam*^ D6 2004 TE 14.5 5,500 Straits Tritton Mines

Tumbarumba Dam* H8 1972/99 TE 20 70 Snowy Valley Council

Tumut Dam No 2* H8 1961 PG 46 3,000 Snowy Hydro Limited

Tumut Dam No 3* H8 1969-71 PG 35 921,000 Snowy Hydro Limited

Tumut Paper Mill Freshwater Dam H8 2001 TE 27 200 Visy Pulp & Paper Pty. Ltd.

Tumut Paper Mill Wastewater Dam H8 2001 TE 10 500 Visy Pulp & Paper Pty. Ltd.

Tumut Pond* H8 1959 PG 86 53,000 Snowy Hydro Limited

Umberumberka Dam* D1 1914 PG/VA 41 8,000 Essential Water

United Colliery Tailings Dam 2* E10 2006 TE 20 800 United Collieries Pty Ltd

Upper Cordeaux Dam 2* G10 1915 VA 21 1,200 WaterNSW

Upper Rodds Creek F8 2001/2012 ER/TE 31 14,500 Cadia Holdings Pty Ltd

Upper Shephards Lane Detention Basin C13 - TE 7 100 Coffs Harbour City Council

Vales Point Ash* F11 1984 TE 6 42,000 Delta Electricity

Valley View Detention Basin F8 2005 TE 5 10 Cowra Shire Council

Wallerawang* F10 1978 TE 14.4 4,300 EnergyAustralia NSW Pty Ltd

Wambo Hunter Pit Tails Dam* E11 2005 ER 50 8,300 Peabody Energy

Wambo South Water*^ E11 2010 TE 8 840 Peabody Energy

Wambo Tailings* E11 1997/2002 TE 50 5,600 Peabody Energy

Warkworth Main Water - Dam 1N E11 1980 TE 8 300 Rio Tinto Coal Australia Pty Ltd

Warkworth North Pit Tailings* E11 1997/2012 TE/ER 65 9,300 Rio Tinto Coal Australia Pty Ltd

Warragamba* [R] F10 1960/90/2002 PG 142 2,030,000 WaterNSW

Warringah Reservoir* F11 1936/95 PG/TE 9.8 80 Sydney Water Corporation

Waverley Reservoir WS133* F11 1917 PG/TE 8.3 19 Sydney Water Corporation

Wentworth Falls Lake*^ F10 1906/91/2003 TE 10 300 Blue Mountains City Council

Werris Creek Void Water 1* D10 2012 TE 5.4 250 Werris Creek Coal P/L


76 ANNUAL REPORT


Storage (ML) Owner

Werris Creek Void Water 3* D10 2012 TE 5 214 Werris Creek Coal P/L

Werris Creek Void Water 4* D10 2012 TE 5 145 Werris Creek Coal P/L

West Epping Park Basin F11 - TE 1.15 1.8 City of Parramatta

Western Sydney Airport Basin 1 - TE 6.75 175 Western Sydney Airport Company

Whitford Road Retarding Basin F10 1997 TE 2.9 38 Liverpool City Council

Widemere Detention Basin F11 2009 TE 9 220 Strata Plus

Wilpinjong TD2* E9 2011 TE 20 4,000 Wilpinjong Coal Pty Ltd

Wilpinjong TD6* E9 2013- TE 22 2,000 Wilpinjong Coal Pty Ltd

Winburndale*^ [R] F9 1936 PG 22 1,700 Bathurst Regional Council

Windamere* E9 1984 TE/ER 67 370,000 WaterNSW

Winding Creek 3 Retarding Basin ?? TE 5 72 Hunter Water Corporation

Winding Creek 5 Retarding Basin E11 1994/2011 TE 6.5 240 Hunter Water Corporation Ltd

Wingecarribee* G10 1974/2012 TE/ER 19 31,600 WaterNSW

Wollondilly Washery 1* G10 1985- TE/ ER 18 70 Burragorang Valley Coal P/L

Wonawinta Tailings* E5 2013 ER/TE 11 1,100 PPB Advisory

Woodford Creek*^ F10 1928/48 VA 16 850 WaterNSW

Woodlawn Mine Evaporation No. 1*^ H9 1989 TE 6 750 Veolia Environmental Services

(Aust) p/l

Woodlawn Mine Evaporation No. 2*^ H9 1989 TE 10 290 Heron Resources Limited

Woodlawn North Tailings*^ H9 1977 TE/ ER 18 2,100 Heron Resources Limited

Woodlawn South Tailings*^ H9 1982 TE/ ER 17 2,400 Heron Resources Limited

Woodlawn Tailings Storage Facility 4^ H9 - TE 25 2500 Heron Resources Limited

Woodlawn West Tailings*^ H9 1989 TE/ER 35 2,400 Heron Resources Limited

Woolgoolga* C13 1967 TE 12 270 Coffs Harbour City Council

Woronora* G10 1941/88 PG 66 71,800 WaterNSW

Wyangala* F8 1961-71/2015 TE/ ER 85 1,220,000 WaterNSW

Wyoming Central Dam E8 2018 TE 6 140 Tomingley Gold Operations p/l

Wyong Road Detention Basin F11 1975 TE 2.7 150 Central Coast Council

Yarrawonga Weir* I6 1939/2001 PG/TE 7 117,500 Murray-Darling Basin Authority

Yass* G8 1927/2013 VA/PG 12 875 Yass Valley Council

Yellow Pinch* I9 1987 ER 40 3,000 Bega Valley Shire Council LEGEND: Applicable as at 30 June 2019 (not including changes between then and printing of Annual Report) Dams added this year to Schedule 1 of the Dams Safety Act 1978 are highlighted rows.

*: Dams with Notification Areas

^: DSC inspected – 2018/2019

-: Not Built

[R]: Significant Risk Dam or requiring specific investigations for particular circumstances

CB: Concrete buttress DR: Decked rockfill ER: Rockfill dam MB: Masonry buttress

PG: Concrete Gravity TE: Earthfill dam VA: Concrete arch

Rushforth Road 100ML Reservoir

Broula King Gold Mine Tailings 2

Northparkes Rosedale Tailings Storage Facility

Yass*

Tooma*

Timor*

Tilba*Geehi*

Oberon*

Medway*

Keepit*

Pindari*

Kalingo*

Googong*

Copeton*

Bootawa*

Boorowa

Rylstone*

Murray 2

Cochrane*

Ben Boyd*

Windamere

Crookwell

Murrurundi*

Burrinjuck*

Burrendong*

Moore Creek*

Yellow Pinch*

Clarrie Hall*

Shannon Creek

Porters Creek*

Lake Inverell

Yarrawonga Weir*

Humphries Creek*

Aldridges Creek

Tenterfield Creek*

Wonawinta Tailings*

Steuart McIntyre Dam*

Northparkes Tailings*

Wollondilly Washery 1*

Maules Creek Mine - RWD2

Humphries Creek Tailings*

McKinnons Gold Mine Tailings

Delegate Flood Retarding Basin*

Hume*

Avon*

Rydal*

Pejar*

Nixon

Mardi*

Lyell*

Brogo*

Sooley*

Nepean*

Malpas*

Tumut 3*

Tumut 2*

Tallowa*

Lostock*

Karangi*

Jounama*

Guthega*

Danjera*

Cowarra*

Company*

Chifley*

Chaffey*

Carcoar*

Wyangala*

Woronora*

The Cove*

Talbingo

Quipolly*

Prospect*

Glenbawn*

Dungowan*

Dumaresq*

Cordeaux*

Cataract*

Bamarang*

Toonumbar*

Suma Park*

Khancoban*

Jindabyne*

Eucumbene*

El Klaros

Coalcliff*

Chinamans

Cascade 1*/2*/3*

Blowering*

Beargamil

Woolgoolga*

Warragamba*

Tumut Pond*

Tumbarumba*

Split Rock*

Deep Creek*

Chichester*

Cambewarra

Winburndale*Wallerawang*

Rocky Creek*Petrochilos*

Narranbulla

Lake Medlow*

Island Bend

Grahamstown*

Spring Creek*

Old Quipolly

Mooney Upper*

Molong Creek*

Fountaindale*

Tantangra Dam*

Redbank Creek*

Lithgow No. 1/2*

Lake Rowlands*Greaves Creek*

Gosling Creek*

Captains Flat*

Beardy Waters*

Woodford Creek*

Wilpinjong TD2*

Port Macquarie*

Mangrove Creek*

Lake Endeavour*

Lake Canobolas*

Kentucky Creek*

Junction Reefs*

Glennies Creek*

Emigrant Creek*

Brennans Creek*

Borenore Creek*

Thompsons Creek*

Tallong Railway*

Hungerford Hill*

Upper Cordeaux 2*

Puddledock Creek*

Emma James Basin

Deep Creek Snowy

Hillgrove Eleanora*

Barden Ridge Lower*

Wentworth Falls Lake*

Tritton Tailings*

Broughton's Pass Weir*

Cowarra Creek Tailings*

Sawyers Swamp Creek Ash*Orange Research Station

Duralie Coal Mine Water*

Maules Creek Mine - MWD2 Hillgrove Tailings No. 1*/2*

Oaky River

Brooklyn Ret. Basin*

Kanahooka Retention Basin

Bagnalls Beach Road Basin

Wyong Road Detention Basin

Northparkes Tailings Dam 2*Mount View Detention Basin

Valley View Detention Basin

Tumut Paper Mill WastewaterTumut Paper Mill Freshwater

Pecan Close Retarding Basin

Bowra*

Cowal Northern/Southern Tailings Dam

Comberton Grange Ret. Basin

Bakers Road Detention Basin

Howell Close Retarding Basin

George Bass Drive Det. Basin

Cowal Gold Mine Reservoir D9

Lake Ettamogah Winter Storage*

Bloomfield U Cut Tailings Dam*

Bennetts Road Detention Basin

Spagnolos Road Detention Basin

Broula King Gold Mine Tailings

Woodlawn Tailings*

Palm Tree Grove Retarding Basin

Duralie Coal Auxiliary Dam No. 1*/2*

Tomingley Residue Storage Facility

Hamilton Valley Retention Basin 5A/5B

Dargues Reef Gold Project Tailings*

Northparkes E27 - Estcourt Tailings*

Upper Shephards Lane Detention Basin

Wilpinjong TD6

Werris Creek Void Water Dams 1*,3*,4*

Mt Boppy Gold Mine TSF

Mineral Hill Tailings/Southern Tailings

Leewood Ponds*

Hera Tailings

East West Road

Jordan Springs

Elanora Country Club Main Dam

Sunrise Mine TSF Cell 2

Calala Raw Water Storage

Narrabri Coal Rail Loop Dams

Western Sydney Airport Basin 1

Sunrise Mine Water Storage Dam

Redbank Dam 14

Boambee Newport Creeks Detention Basin

Wyoming Central Dam

Tarrawonga Clean Water Dam

Eurobodalla Southern Storage

West Epping Park Basin

The Gables Lake and Basin

Cowal Integrated Waste Landform

Springvale Reject Emplacement Area*

Adelong Tailings Dam

Nyngan Evaporation Pond /Nyngan TSF*

Diamond Circuit Detention Basin

Schofields North/South Rail Facility

Bingara Gorge Pond 1

Woodlawn Tailings Storage Facility 4

Korrumbyn Creek

Corindi Stage 3 Dam

Connors Creek Dam

Sarah Fahey Park Retarding Basin

Redbank Dam 13

Northparkes Infill Tailings Storage Facility

Dobinson Retarding Basin

Eden

Bega

Yass

TareeScone

Dubbo

Moree

Cowra

Cooma

Coolah

Parkes

Walcha

Forbes

Albury

Orange

Mudgee

Nyngan

Casino

Temora

Thredbo

Ballina

Kempsey

Grafton

Maitland

CANBERRA

Goulburn

Tamworth

Narrabri

Inverell

Griffith

Singleton

Newcastle

Queanbeyan

Brewarrina

Narrandera

Glen Innes

Condobolin

Goondiwindi

Wagga Wagga

Murwillumbah

Batemans Bay

Muswellbrook

West Wyalong

Coonabarabran

Coffs Harbour

Port Macquarie

Tumut

Nowra

Penrith

154°0'0"E

154°0'0"E

153°0'0"E

153°0'0"E

152°0'0"E

152°0'0"E

151°0'0"E

151°0'0"E

150°0'0"E

150°0'0"E

149°0'0"E

149°0'0"E

148°0'0"E

148°0'0"E

147°0'0"E

147°0'0"E

146°0'0"E

146°0'0"E

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29°0'0"S 29°0'0"S

30°0'0"S 30°0'0"S

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Antiene Lease Tailings*Bayswater 2 Main*Bayswater Ash* Bayswater Brine Decant*Bayswater Cooling* Bengalla Stage Discharge*Bulga Coal CHPP Surge Dam Bulga Mine Water Dam* Camberwell Tails2*Cumnock Tailings* Dartbrook Mine Water* Hunter Valley Operations Dam6 TSF Liddell Ash* Liddell Ash Disposal Liddell Ash Levee*Liddell Cooling Water* Liddell WS* Mangoola Coal Raw Water*Mangoola Start-up Tailings*Mangoola Pit Water*Mt Arthur North Environmental*Mt Arthur Tailings Storage Facility*Mt Owen Rail LoopMt Thorley Abbey Green South*Mt Owen North Void Tails*Mt Thorley Central Ramp Tails* Plashett*Ravensworth Void4*, Void5*Ravensworth InpitRavensworth South Tailings*SE Tails United Colliery Tailings 2*Wambo Tails*Wambo Hunter Pit Tails*Warkworth Nth Pit Tailings*Wambo South Water*

NSW Dams Safety CommitteePRESCRIBED DAMS IN NSW

JULY 2019

Cadiangullong*Cadia Tailings*Cadia Southern Tailings*Cadia North Waste Dump Det. BasinUpper Rodds Ck

Colongra Ck*Eraring Ash*Eraring Attemp. Cooling Water* Mannering Creek Ash*Vales Point Ash*

Blackbutt Reserve*Brokers Road Ret BasinBucklands Ret BasinEdgewoord Det BasinFoothills Estate Ret Basins 1 & 3Foothills Road BasinGannet Place Ret. BasinGreen Meadows Ret BasinGunyah Park BasinKanahooka Ret BasinNyrang Pk Ret BasinOak Flats Reservoir*Shellcove Estate Det Basin1South Bulli Basin1South Bulli StormwaterSt Josephs School Ret Basin

EDGEWORTH DBFloraville Rd Det BasinGarden Suburb Det. Basin2Minmi Road Detention BasinNewstan Southern REA Main Tails* Seladon Avenue Ret Basin Stockton Borehole Tails* Winding Ck 5 Ret Basin

Bendeela Pondage*Bundanoon*Fitzroy Falls*Glenquarry Cut*Kangaroo Pipeline*Wingecarribee*

6 7 8 9 10 11 1312

A

G

C

F

B

D

E

H

J

I

Elura Tailings

Wonawinta Tailings*

CSA South Tailings*

Peak Gold Mine Tailings*

McKinnons Gold Mine Tailings

Tritton Tailings*

Mt Boppy Gold Mine TSF

Hera Tailings

Nyngan Evaporation Pond /Nyngan TSF* Cobar

CSIRO Ret BasinDEP Ret BasinFox Hills Ret BasinGeorgia Terrace Det. BasinGlenmore Park Ret. Basin 4Gooden Reserve Det. Basin Hoxton Park Basin 6Knight ParkLake Parramatta*Loyalty Rd BasinMcCoy Park BasinMuirfield Golf ClubMuirfield Golf Course Det. BasinNorbrik Detention PondNorthmead Reserve Det. BasinNth Turramurra Golf ClubPied Piper Playground Det. BasinRouse Hill Basins 5, 9A, 9B,13,16 School House Creek BasinSierra Place Det. BasinThornleigh Res*Widemere Det. Basin

Abbottsbury Pk Pond 2Banks Rd BasinBosnjak Park USCecil Hills Basin 100, 3A*Cecil Park Basin 3BClear Paddock Basin CClear Paddock Creek Basin W2, W3Comin Pl. Det BasinDaruk Pk Ret BasinEdmondson Park Basin 12Emerson Street Detention BasinFairfield Golf Course BasinGreenway Drive Basin 10A/BHorningsea Park Retarding BasinKing Park BasinMimosa Road BasinStockdale BasinWhitford Road Ret. Basin

Lidcombe B6Potts Hill Reservoir 2*

Cambelltown Link Area Basin1 Campbelltown Nth Det Basin Mt Annan Wetland No 1* Smiths Ck Basins 1,2,3

Honeysuckle CreekKillara Reservoir*Manly*Pymble Golf CourseWarringah Reservoir*

Inset

D

5

Cootamundra

Lake Cargelligo

Wellington

SYDNEY

Wollongong

Armidale

Lithgow

Gosford

Ashton Coal Clean Water Dam1* Bengalla CW1* Bengalla CW1* Bulga Northern Tailings Dam A Bulga Old Tailings* Carrington in-pit Tailings Storage Facility Cumnock Tailings Storage Facility No.3* Drayton Water Supply* Drayton In-pit Long Term TSF Drayton In-pit Temporary TSF Houston Hunter Valley Operations Lake James Mt Thorley South Out of Pit Water* Montrose Mount Pleasant Dams - 1,3, MWD, Environmental and Tailings Possum Skin Dam* Riverview Void In-Pit Water Storage*

Barina Park Detention BasinShellharbour City Centre Basin

A "prescribed dam" is a dam included on Schedule 1 of the Dams Safety Act 1978 * Mining Notification Area defined

Centennial Park Res 1* & 2* Dover Hts Res* Kensington Centennial Park PondMarrickville Oval Retarding Basin Maroubra Res*Waverley Res*St Peters Basin - 9SWB01

Dams added to Schedule 1 of the Dams Safety Act during 2018/19 are shown in orange

Umberumberka*

Site D Tailings

Menindee Lakes Storage*

Imperial Lake*

Stephens Creek*

Blackwood Pit TSF*

Menindee

Broken Hill

InsetF

E

D 2

Winding Ck 3 Ret Basin

MacDonalds Dam

Bulga Nth Inpit Tailings

Dams Safety Committee Annual Report 2018 / 2019 · NSW Dams Safety Committee Annual Report 2016 /...

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Transcript of Dams Safety Committee Annual Report 2018 / 2019 · NSW Dams Safety Committee Annual Report 2016 /...