Great Lakes Water Quality Improvement Plan · Great Lakes Water Quality Improvement Plan: Wallis,...

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- i - Great Lakes Water Quality Improvement Plan Wallis, Smiths and Myall Lakes Great Lakes Coastal Catchments Initiative

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Page 1: Great Lakes Water Quality Improvement Plan · Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes Acknowledgements Presented in alphabetical order Reviewers

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Great LakesWater Quality

Improvement Plan Wallis, Smiths and Myall Lakes

Great Lakes Coastal Catchments Initiative

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Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes

Cover photos (clockwise from top left): Signing Statements of Joint Intent (K Meares), Smiths Lake (A Staniland) and off-stream watering (A Fardell). Great Lakes Water Quality Improvement Plan Copyright © 2009 This publication is copyright. You may download, display, print and reproduce this material in an unaltered form only for your personal use or for non-commercial use within your organisation. To copy, adapt, publish, distribute or commercialise any of this publication you will need to seek permission from Great Lakes Council. Great Lakes Council PO Box 450 Forster NSW 2428 Citation: Great Lakes Council 2009, Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall Lakes, Forster, NSW Acknowledgements are presented in alphabetical order Authors:

Ian Armstrong (Batkin Walkerden Associates) Craig Aspinall (Hunter-Central Rivers Catchment Management Authority) Pam Batkin (Batkin Walkerden Associates) Peter Beale (Department of Primary Industries) Mat Bell (Great Lakes Council) Naomi Brydon (Integrated Catchment Assessment and

Management (iCAM) Centre, The Australian National University) Victoria Coleman (Independent Sustainability Consultant) Jocelyn Dela-Cruz (Department of Environment and Climate Change) Robert Gillespie (Consultant) Brendan Haine (Department of Environment and Climate Change) Rebecca Kelly (Integrated Catchment Assessment and

Management (iCAM) Centre, The Australian National University) April McKay (Great Lakes Council) Kate Meares (Great Lakes Council) Wendy Merritt (Integrated Catchment Assessment and

Management (iCAM) Centre, The Australian National University) Peter Scanes (Department of Environment and Climate Change) Mike Smith (Great Lakes Council) Prudence Tucker (Great Lakes Council) Gerard Tuckerman (Great Lakes Council) Greg Walkerden (Batkin Walkerden Associates) Tony Weber (BMT WBM Pty Ltd)

DISCLAIMER The information contained within this publication is based on knowledge and understanding at the time of writing (August 2008). However, because of advances in knowledge, users are reminded of the need to ensure the information they rely upon is current and accurate.

The views and opinions expressed in this publication are those of the authors and contributors, and do not necessarily reflect those of the Australian Government or the Minister for the Environment, Heritage and the Arts or the Minister for Climate Change and Water.

The Great Lakes Water Quality Improvement Plan was produced through The Coastal Catchments Initiative, an Australian Government-funded project with contributions from Great Lakes Council, and the Department of Environment and Climate Change.

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Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes

Acknowledgements Presented in alphabetical order Reviewers / Advisors Advisory Committee

Craig Aspinall (Hunter-Central Rivers Catchment Management Authority) David Bell / Danny Elliott (Wallis Lake Fishermen’s Co-operative) George Beverley (Wallis Lake Catchment Management Plan committee

representative) Linda Brook-Franklin (MidCoast Water) Roger Busby (Great Lakes Council) Graham Carter (Department of Water and Energy) Hugh Cross (Hunter-Central Coast Regional Environment Management Strategy) Brett Currie (Greater Taree City Council) Richard Ellery (Wallis Lake Shellfish Program) Jason Everett (Smiths Lake Estuary Management Committee representative) Kim Forbes / Neal Hardy (Department of Environment, Water, Heritage and the Arts) Glenn Handford (Great Lakes Council) Max Haste / Richard McEvilly (Port Stephens Great Lakes Marine Park Authority) Sally Hunt (Department of Environment, Water, Heritage and the Arts) Albert Mullen (Sustainable Grazing Officer) Jeff Palmer (Hunter-Central Rivers Catchment Management Authority) Bruce Pease (Department of Primary Industries) Matt Ravell (Oyster industry representative) Les Roberts (Karuah Great Lakes Landcare group) Peter Scanes (Department of Environment and Climate Change) Kath Smith (Community Representative) Stephen Smith / Fiona Miller (Department of Environment and Climate Change) Gerard Tuckerman (Great Lakes Council) John Wilson / Glenda Briggs (Department of Primary Industries)

Rural Management Practices Technical Group

Peter Beale (Department of Primary Industries) Geoff LeMessurier (Hunter-Central Rivers Catchment Management Authority) Albert Mullen (Sustainable Grazing Officer) Danny Norris (Department of Primary Industries) Les Roberts (Karuah Great Lakes Landcare group) Stacey Tyack (Great Lakes Council)

Lake Use and Pollution Control Workshop participants / contributors

Wayne Burgess (Great Lakes Council) Scott Carter (Department of Primary Industries) Brett Currie (Greater Taree City Council) Tim Gippel (Department of Primary Industries) Greg Golby (Wallis Lake Fisherman) Malcolm Hunter (Great Lakes Council) Richard McEvilly (Port Stephens Great Lakes Marine Park Authority) Gary Mead (Great Lakes Council) Brett Ryan (Maritime Authority) Anthony Sciacca (Oyster industry representative) Robyn Shelley (Great Lakes Council) Gerard Tuckerman (Great Lakes Council) Steve Verdich (Oyster industry representative) Tony Woodford (Maritime Authority) Robert Williamson (Maritime Authority) Anthony Zammit (NSW Food Authority)

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Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes

WSUD external group Garry Beisser (G&A Beisser) Hugh Cross (Hunter Councils) Bill Donohoe (Badcock & Brown Residential Land Partners) Georg Fiebig (Pacific Blue Design) David Green (Hunter-Central Rivers Catchment Management Authority) Jacquie Keats (Great Lakes Environment Association) Bob Lander (Tattersall Surveyors) Bill Sarkis / Willander Ooi (Winten Property Group) Gavin Maberley-Smith (Coast Plan Consulting) Ian Sercombe (Great Lakes Ecollective) Mike Sharpin (Department of Environment and Climate Change) Michael Summers (Lidbury, Summers & Whiteman)

WSUD internal group Brian Brooker (Great Lakes Council)

Wayne Burgess / Robyn Shelley / Alan Baldwin (Great Lakes Council)

Roger Busby (Great Lakes Council) Bruce Byatt (Greater Taree City Council) Alex Caras (Great Lakes Council) Ajith De Alwis (Great Lakes Council) Steve Glendenning (Great Lakes Council) Ian Greenham (Great Lakes Council) Brendan Guiney (MidCoast Water) Kumar Kuruppu (Great Lakes Council) Greg Pitt / Mike Keegan (Great Lakes Council) Garry Schultz (Greater Taree City Council) Prudence Tucker (Great Lakes Council) Gerard Tuckerman (Great Lakes Council) Graeme Watkins (MidCoast Water) Management Systems group (Adaptive Management, Institutional Arrangements, Financial Strategy)

Brett Currie (Greater Taree City Council) Jeff Palmer (Hunter-Central Rivers Catchment Management Authority) Prudence Tucker (Great Lakes Council) Gerard Tuckerman (Great Lakes Council) Graeme Watkins (MidCoast Water) Brendan Guiney / David McKellar (MidCoast Water)

Landholder Reference Group

Steve Atkins Kay Bartlett Art Brown Norm Cunningham Andy Gilbert Trevor McBride Bill Phair Win Rae Les Roberts David Whamond

Other reviewers

April McKay (Great Lakes Council) Andrew Staniland (Great Lakes Council) Isabelle Strachan (Great Lakes Council)

Community groups who provided input during WQIP development Bunyah Landcare

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Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes

Dyers Crossing Landcare Forster University of the 3rd Age Wallis Lake Fishermen’s Co-operative Getaway Luxury Houseboats Great Lakes Coastal Land Management Network Hawks Nest / Tea Gardens Progress Association Karuah Great Lakes Landcare Myall Koala and Environment Support Group Myall River landholders Nabiac Landcare Wallis Lake oyster growers Pindimar Bundabah Community Association Smiths Lake Estuary Management Committee Smiths Lake Landcare Wallis Catchment landholders and landholder survey participants Myall Catchment landholders Wallis Lake Estuary Management Committee Wallis Lake Catchment Implementation Committee

Project and research teams Great Lakes Council (Project coordination and development)

Richard Henry (Assistant Project Manager) Kate Meares (Project Assistant) Mike Smith (GIS Officer) Prudence Tucker (Project Coordinator)

Department of Environment and Climate Change (Catchment and estuary research and modelling)

Max Carpenter (Environmental Technician) Geoff Coade (Senior Scientist – Estuary processes) Ed Czobik (Senior Chemist) Jocelyn Dela-Cruz (Senior Scientist – Catchment processes) Katelyn Edge (Environmental Assistant) Brendan Haine (Scientist – Catchment and estuary processes) April McKay (Environmental Assistant) Adam McSorley (Environmental Technician) Jamie Potts (Senior Scientist – Estuary processes) Brian Sanderson (Senior Scientist – Estuary modeller) Peter Scanes (Project and Team Manager) Renelle Watson (Scientist – Catchment processes) Yi Lu (Scientist – Catchment processes)

ANU: iCAM (Decision Support System development)

Naomi Brydon (Research Assistant) Natasha Herron (Research Fellow) Rebecca Kelly (Research Fellow) Peter Manger (Software Developer) Wendy Merritt (Research Fellow) Kirien Whan (Research Assistant)

Batkin Walkerden Associates (Management systems, pollution control systems, offset scheme scoping, Water Sensitive Urban Design Strategy)

Pam Batkin (General Manager) Greg Walkerden (Environmental Manager) Ian Armstrong (Environmental Scientist)

Department of Primary Industries (Landholder survey, literature review, nutrient budgets)

Peter Beale (District Agronomist) Kim Billingham (Researcher) Tina Dalby (Researcher)

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Great Lakes Water Quality Improvement Plan: Wallis, Smiths and Myall lakes

Roy Laurie (Researcher)

BMT WBM (Urban stormwater modelling) Tony Weber (Manager, Water Quality) Tony McAlister (Director, Water and Environment) Mark Wainwright (Associate) Gillespie Economics (Environmental economics) Robert Gillespie (Consultant)[pt1]

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EXECUTIVE SUMMARY

Wallis Lake, Smiths Lake and Myall Lakes and their catchments are located on the Mid North Coast of

New South Wales. These lakes are the subject of this Water Quality Improvement Plan (WQIP).

The ecological significance of these lakes and their catchments have long been recognised at local,

state, national and international levels as documented in the relevant estuary and catchment

management plans. Formal recognition of ecological values varies across the area and includes national

park estate (including the Port Stephens–Great Lakes Marine Park), international migratory bird

agreements such as Japan–Australia Migratory Bird Agreement (JAMBA) and China–Australia Migratory

Bird Agreement (CAMBA), and recognition of wetlands of national and international importance including

Ramsar listing for the Myall Lakes.

This plan further recognises the significance of these systems, drawing on new research, modelling and

community engagement to identify a range of rehabilitation, protection and management support actions

to protect and support (and where required, restore) the ecological health of these systems.

In 2005, the Australian Government provided funding to Great Lakes Council through the Coastal

Catchments Initiative (CCI) to undertake research and develop this WQIP. The aims of the project were

to:

identify the specific levels of nutrients and sediments that are required to provide conditions for a

healthy lake ecology and environmental values desired by the community,

identify the best way to manage activities to reduce key pollutant loads entering the lakes

review pollution control and faecal coliform management systems as they pertain to the management

and protection of the lakes.

The WQIP has been developed for practitioners and catchment / estuary management groups. It is

divided into three parts:

PART 1: CCI planning process

Provides a background to the Coastal Catchments Initiative and the process of developing the WQIP

PART 2: Individual lake Water Quality Improvement Plan actions

o Wallis Lake – research results, ecological targets, catchment management actions and

associated costs for the Wallis Lake catchment

o Smiths Lake – research results, ecological targets, catchment management actions and

associated costs for the Smiths Lake catchment

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o Myall Lakes – research results, targets, catchment management actions and associated costs for

the Myall Lakes catchment.

PART 3: Implementation framework

Covers detailed management and support actions that are to be used to implement the plan across

all three lakes, covering rural land, rural residential and urban land, lake use, pollution control

systems, institutional arrangements, and adaptive management.[NB2]

Developing the Water Quality Improvement Plan

The WQIP has been developed in partnership with agencies, industry groups and the community. The

focus of the planning process was to provide opportunities for capacity building and joint learning with

stakeholders, as well as create opportunities to build awareness within the general community about

water quality issues and catchment management. The engagement of stakeholders in developing the

WQIP, and the nature and level of their involvement, has been summarised below.

Table 0.1. [DG3]Stakeholder engagement in WQIP development

Stakeholders engaged Nature of engagement

Advisory Committee A total of 25 people representing 20 groups were engaged to provide strategic input to the CCI. There were 17 meetings held to allow information exchange between members and the project where decisions were made on the strategies to include in the WQIP

Rural Management Practice Technical Committee

This was a committee of catchment management practitioners with landholder representation to inform the rural part of the project. Between three and 16 members attended 25 meetings, workshops and field visits to provide input on rural management actions to include in the Farm Scale Action Plan.

Landholder Reference Group

This was a group of landholders from across the project area formed to provide on-ground input to rural management ideas in association with the Rural Management Practice Technical Committee. Two workshops with this group of six landholders helped to inform the Farm Scale Action Plan, ensuring that the recommendations in the plan were implementable and practical.

Individual landholders and landcare groups

A total of 55 landholders completed surveys, and several landholders allowed research to be conducted on their properties to better inform the rural part of the plan. Many of these landholders also provided direct feedback on management ideas at workshops, as did several members of local landcare groups.

General community – groups and individuals

A total of 175 interested people (representing 16 groups) helped review the environmental values of the three lakes and provide general suggestions. There were 62 community members who reviewed and suggested catchment management strategies at workshops. A total of 230 people were provided with a presentation on the CCI at two information sessions. Also,the general public received information through the media.

Internal Water Sensitive Urban Design stakeholder group

Between 10 and 14 officers from Great Lakes Council and MidCoast Water attended four internal working group meetings to help inform urban actions in the WQIP.

External Water Sensitive Urban Design stakeholder group

Between seven and 14 stakeholders from building, architecture, design and planning companies attended three meetings to ensure the recommendations in the plan for urban areas were implementable and practical from an industry perspective.

Management Systems group

Between five and nine officers from Great Lakes and Greater Taree councils, and MidCoast Water, attended three meetings to provide input on the types of systems needed to ensure the recommended actions would be implemented.

Other government agencies and groups

Ten agency stakeholders attended a full-day workshop to review current pollution control systems. A total of 23 presentations on the CCI were made to other agencies, boards and committees.

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In developing the WQIP, the Great Lakes Coastal Catchments Initiative had three main components:

water quality research to identify the current status of the systems, and develop catchment and

estuarine models of sediment and nutrient loads to the Myall, Smiths and Wallis lakes

identifying rural, urban, rural residential and management support actions to reduce sediment and

nutrient loads entering the lakes

a decision-support system to assist with decision-making in relation to how activities on the land will

impact on water quality and ecology of the lakes.

Water Quality Improvement Plan summary

The Water Quality Improvement Plan focuses on algae concentration and water clarity as indicators of

the estuaries’ ecological condition. These parameters were selected, as increased algal biomass and

deceased water clarity can lead to harmful algal blooms, loss of habitat such as seagrass, reduced fish

abundance, loss of higher predators (e.g. birds, dolphins, sharks), and overall loss of biodiversity and

estuarine function. The WQIP used abundance of microalgae (chlorophyll-a), water clarity (turbidity,

Secchi depth) and the extent of seagrass as the primary indicators of estuarine condition. Water clarity

and chlorophyll-a concentrations were considered to be the appropriate measures of ecological condition

– rather than water quality parameters – because they were direct measures of ecosystem status and

were the only indicators of condition linked to catchment disturbance.

To determine the actions required to maintain or improve the ecological health of the systems, the

current status of the lakes and the river estuaries were identified and ranked in relation to their relative

conservation values. Conservation values were established based on the chlorophyll-a concentration

recorded in the field. Three levels were established:

1. High conservation value

2. Moderately disturbed

3. Heavily impacted.

Current condition of the lakes and ecological condition targets

Wallis Lake

The southern end of Wallis Lake is in a High conservation value or near-pristine state. It supports a

wide variety of seagrass, healthy algae and brackish water plant (macrophyte) communities to a depth in

excess of 3 m. All these benthic (bottom-dwelling) plant communities are dependent on clear, clean

water with very low nutrient loads. These near-pristine conditions have allowed the continued survival of

the ecologically important seagrass and macrophyte communities, with their associated biodiversity

(including the increasingly threatened estuarine sponges found to be present). The long-term target

identified for the southern end of the lake was to maintain its current near-pristine condition.

Localised conservation value issues were identified in a number of areas.

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In Coomba Bay area, chlorophyll-a measurement showed elevated concentrations when compared with

the southern bays of the main Wallis Lake body. A large gully estimated to be up to 300 m long, 3–4 m

wide and 2 m deep – which resulted from a failed dam – exported a large volume of sediment into the

waters of the bay. In this event, seagrass communities were killed due to burial and the resuspension of

the deposited sediments that caused long-term turbidity. The impact of a seemingly small failure in

catchment management emphasises the scale of risk that can stem from localised catchment conditions.

The long-term target identified for Coomba Bay is to improve its current condition to more closely

resemble High conservation value conditions. This means chlorophyll-a levels need to be reduced by

41%.

The Pipers Creek and Pipers Bay area is the receiving waters for the medium-density urban and light

industrial developments on the eastern side of the Wallis Lake, and includes the majority of the Forster

urban area. Chlorophyll-a concentrations in Pipers Creek were among the highest measured in the

system, with the average value five to six times greater than values expected for this type of

environment. The research indicated that this part of Wallis Lake is significantly degraded, with extensive

macroalgae growth recorded on the seagrass. This area was identified as in the lower end of the range

for a Slightly to moderately disturbed ecosystem value. The long-term target for the Pipers Bay area is to

improve its current modified condition to more closely resemble a High conservation value condition.

This means chlorophyll-a levels need to be reduced by 50%. This will also provide a degree of protection

to the main Wallis Lake body because during high-flow periods, pollutants flow from Pipers Bay towards

the southern bays of Wallis Lake.

The lower Wallis Lake estuary (comprising the lower reaches of the Wallamba, Wang Wauk and

Coolongolook Rivers; the lake entrance; and the eastern and western channels), despite receiving much

of the catchment input of pollutants from the major rivers, was determined to be generally in good

condition. This area is well flushed (i.e. there is significant tidal exchange with the ocean) when

compared to other parts of the system. The lower Wallis Lake estuary was determined to be in the lower

category of High conservation value. Given that the lower estuary is where most of the aquaculture and

lake-based recreation occurs, the long-term target is to maintain and, where possible, improve on current

conditions to provide a buffer against possible future increases in pollutants, including those arising from

single, localised events.

While the lower reaches of the Wallamba, Wang Wauk and Coolongolook rivers have good ecological

condition, the middle reach of the Wallamba river estuary has an ecological condition that is Slightly

to moderately disturbed. The middle reach of the Coolongolook and Wang Wauk river estuary are

also Slightly to moderately disturbed, although they are in better condition than the middle reach of the

Wallamba River. The adopted long-term target for the middle reaches of the Wallamba, Coolongolook

and Wang Wauk River estuaries was to improve from their current modified condition to more closely

resemble High conservation value conditions. This requires a long-term reduction in chlorophyll-a by

21% in the Wallamba River, 14% in the Coolongolook River and 2.7% in the Wang Wauk River.

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The upper reach of the Wallamba river estuary has an ecological condition that is Slightly to

moderately disturbed. The degree of impact is higher than the middle reaches of the river. The plan

recommends that the upper reaches of the Wallamba river estuary be managed to improve it from its

current modified condition to more closely resemble High conservation value conditions. The long-term

goal requires a 30% reduction in chlorophyll-a.

Smiths Lake

The current ecological condition of Smiths Lake was identified as of High conservation value. The

ecological condition target identified for Smiths Lake is to maintain its high conservation value and,

where possible, improve on current conditions to provide a buffer against possible future increases in

pollutants or impacts of lake use activities.

Myall Lakes

Myall Lake and Boolambayte Lake both have a good ecosystem quality and were considered to be of

High conservation value. Two Mile Lake, while generally in good condition, has experienced higher

levels of chlorophyll-a and nuisance algal growth, and appeared to have lost some deepwater plant

communities at its southern end. The adopted long-term targets for Myall Lake and Boolambayte Lake

are to maintain and, where possible, improve on current conditions to provide a buffer against possible

future increases in pollutants. This was considered especially important, given that it is a Ramsar site

(Wetland of International Importance).

Bombah Broadwater, in the Myall Lakes, is a Slightly to moderately disturbed ecosystem. The Bombah

Broadwater has experienced some severe algal blooms over the past decade and the apparent loss of

deepwater plant communities. The long-term target for the Bombah Broadwater is to improve its current

modified condition to more closely resemble a High conservation value condition. This requires a 14%

reduction in chlorophyll-a levels.

Management strategies

The strategies outlined in the WQIP targeted two specific purposes:

to remediate existing areas of high pollutant loads, and thus reduce catchment loads and improve

estuarine health

to protect areas of high conservation status that currently provide substantial water quality and

biodiversity benefits to the rivers and lake systems.

While protection actions were not expected to improve water quality as such, the plan highlights that it is

essential to protect against further declines in water quality. The WQIP confirms that it is more important

and less expensive to protect current values and functions than to replace them once they have been

lost. Given the cost of remediation actions and the limits to their effectiveness to improve water quality at

the catchment scale, the WQIP [pt4]indicates that it is essential that a range of protective actions is

implemented. Protection actions identified included maintaining existing vegetation buffers and placing

limits on and controlling inappropriate development. This is particularly the case for the southern end of

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Wallis Lake where the unique ecological values are at risk if significant protection of current values and

functions is not undertaken.

A summary of the programs identified in the WQIP is shown below. The nature of the programs is similar

between lakes. However, the extent of each program varies. This variation was based largely on the

ecological condition of each lake (and therefore the amount of remediation or protection actions

required), dominant land uses in each catchment and the feasibility of the adoption of actions in each

area.

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Table 0.2. Remediation actions proposed in the Water Quality Improvement Plan.

Program Program description Lakes Plan section

Rural land

Groundcover management

The aim of this program is to improve groundcover on rural lands, thus reducing the amount of sediments and nutrients washing into the waterways. Groundcover management refers to a sustainable grazing program for landholders, and is focussed on improving groundcover management on pasture lands. It involves field days and formal workshops with experts, developing information and training material on stocking rates, formal training courses such as Prograze, a dung beetle release program, and a program of on-ground works that will assist landholders to better manage groundcover levels (including off-stream watering, solar pumps and fencing).

Myall Wallis Smiths

3.3.2

Nutrient (Fertiliser) management

Nutrient management is a component of a sustainable grazing program focussed on the appropriate application and storage of nutrients. It involves working with landholders to trial different types of fertilisers, formal training courses such as LANDSCAN, subsidising and promoting the use of soil tests, and providing assistance with interpretation of the tests so that the results can be integrated into a whole-farm plan. This program also supports a dung beetle program.

Additional actions related to the management of human and animal effluent include the upgrade of laneways and stock crossings. However, these kinds of actions, although recommended by the plan, were not modelled through the CCI project.

Myall Wallis

3.3.2

Infrastructure (Dam) management

Infrastructure management includes the refurbishment of dams that are a water quality risk as well as decommissioning those dams that are not functioning, and potentially acting as a source of nutrients and sediments to the system. It involves working with landholders to repair dam structural problems, controlling stock access to the dam or providing an alternative stock water supply from the dam. It also involves landholder training, as well as training and accreditation of contractors.

Additional actions relating to the management of infrastructure have also been identified, including road and laneway management. However, these kinds of actions were not able to be modelled.

Myall Wallis

3.3.2

Riparian remediation Riparian remediation programs include the rehabilitation of sites with active stream bank erosion. These sites are based on identified locations in existing plans, such as rivercare plans. This program includes significant in-stream repair work for bank stabilisation and fencing off the creek in identified areas.

Myall Wallis

3.3.2

Unpaved road remediation

This aims to identify and seal unpaved roads in priority areas, such as creek crossings in the Smiths Lake catchment and the Crawford sub-catchment of the Myall Lakes system. This would also include installing best practice sediment and erosion control features, such as mitre drains to divert road runoff into grassed areas.

Smiths Myall

3.3.2

Urban land

Urban Mitigation (Water Sensitive Urban Design)

Urban mitigation includes the retrofitting of rainwater tanks supported through a program of rebates. It is recommended that the tanks are plumbed into the home to maximise the water quality benefits. It also involves an extensive program of urban retrofitting where Water Sensitive Urban Design (WSUD) systems, such as biofiltration (including trenches, raingardens and biopods), are built into the existing urban landscape to filter the urban stormwater. For Wallis Lake, the focus areas are the catchments of Pipers Creek and Pipers Bay. In Smiths Lake, the focus is in the existing urban area. This program also involves education and capacity-building on maintenance and construction of WSUD devices, adoption of a development control plan that specifies best practice water-sensitive urban design, and associated staff training and capacity-building. It also includes investigating options for a nutrient offset scheme for the Pipers Creek / Pipers Bay area.

Wallis Smiths

3.4.2

Water Sensitive Redevelopment

Water Sensitive Redevelopment involves the implementation of a development control plan that specifies best practice water-sensitive urban design (including biofiltration and rainwater tanks) on all redevelopments. The program of redevelopment has been estimated based on existing redevelopment rates.

Wallis

3.4.2

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Table 0.3. Protection actions proposed in the Water Quality Improvement Plan.

Program Program description Lakes Plan section

Rural land

Wetland protection

Wetland protection involves the acquisition of wetlands, and undertaking management and / or rehabilitation as required (e.g. fencing, establishing property vegetation plans, management plans, reinstating natural hydrology). The program also involves assisting landholders to protect natural wetlands, with advice, training and on-ground works to control stock access. More generally, the program involves partnerships with the community, including raising the profile of wetlands and their role in providing environmental services, as well as encouraging participation in management and restoration.

Wallis Myall

3.3.2

Riparian protection

This program involves fencing and / or stock exclusion of areas of riparian revegetation, including off-stream watering and some planting where vegetation requires rehabilitation. It also involves establishing property vegetation plans in areas not suitable for fencing (e.g. high-slope areas).

Myall Wallis

3.3.2

Urban land

Water Sensitive Development of Greenfield sites

Water- Sensitive Development of Greenfield sites involves establishing and implementing Local Environmental Plan (LEP) / Development Control Plan (DCP) provisions on Greenfield development sites in the Wallis Lake catchment. This will involve enforcing ‘no net increase’ in pollutants relative to the existing land use (agricultural and forest land use classifications). This program also involves establishing heads of consideration for voluntary planning agreements with developers.

Wallis Smiths Myall

3.4.2

Water Sensitive Redevelopment

Water Sensitive Redevelopment involves the implementation of a development control plan that specifies best practice water-sensitive urban design (including biofiltration and rainwater tanks) on all redevelopments. Predicted redevelopment rates in the Smiths and Myall lakes are low, and therefore in these areas it is considered a protection action.

Smiths Myall 3.4.2

Water Sensitive Urban Design protection

WSUD protection is an education and capacity-building program on stormwater management, including water-sensitive urban design and improved management of urban land. It involves workshops, field days and demonstration sites with stakeholders including the general community, business, students, and building and development industries. It involves updating plans, strategies and design guidelines (such as road guidelines), as well as resourcing a sediment and erosion control audit and training program.

Wallis Smiths Myall

3.4.2

Foreshore and riparian management in urban areas

Foreshore and riparian management in urban areas involves improving foreshore areas around Wallis and Smiths lakes through establishing site-specific management plans, education and engagement of residents surrounding foreshore areas to reduce the impact of their behaviours, and increased enforcement of environmental legislation in these areas.

Wallis Smiths

3.4.2

Best management of unpaved roads

Best management of unpaved roads includes construction of mitre drains to divert road runoff into grassed areas, and sealing and diverting runoff away from streams particularly in the vicinity of creek crossings. The program involves mapping the location and extent of road erosion sites, and undertaking risk analysis in each sub-catchment to prioritise roads for rehabilitation or closure. A program of training and auditing contractors and council staff specific to road construction to ensure best management practices are applied will also be undertaken as part of this action.

Wallis Smiths Myall

3.3.3

Other

Protect sea sponge beds

To facilitate the protection of the unique sea sponges in Wallis Lake, identification and mapping of the location of sea sponges, and developing and implementing an action plan and case for formal protection, are required. This program also involves engaging with the community and key stakeholders to establish support for protection, as well as establishing appropriate community education and monitoring programs.

Wallis

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Program Program description Lakes Plan section

Improved management of lake use activities

Improved management of lake use activities involves reviewing stormwater management plans to clarify the outcomes required to protect the environment and oyster growing programs to identify synergies with ecological monitoring programs (Wallis Lake). It also involves establishing memoranda of understanding with key groups of lake users, and investigating other management options such as closing boat ramps during high-flow events (Wallis Lake) and establishing markers to protect seagrass beds (all lakes). It also involves supporting actions in the Smiths Lake boating plan. In Myall Lakes, it recommends upgrading gravel boat ramps, assessing impacts of water sports and adopting no-discharge guidelines for greywater.

Wallis Smiths Myall

3.5.2

Improved pollution control systems / management systems

Improved management and pollution control systems involves reviewing how water quality management, both within and between organisations, is approached. It focuses on establishing checking and review loops in key areas, such as compliance with conditions of consent, and sediment and erosion control. The program also highlights the need to embed water quality improvement actions in organisational plans to ensure the WQIP is implemented. It highlights the need to review a range of existing systems such as the fee structure for on-site sewage management, and recommends exploring alternative ways to formalise the response to complex pollution cases and strengthen cross-agency relationships and delegation.

Wallis Smiths Myall

3.7

Management support actions

Adaptive Management Strategy / Ecological monitoring program

The Adaptive Management Strategy underpins the implementation of the WQIP. It highlights the ecological, political and social uncertainties surrounding the WQIP, and identifies ways to track these and make informed management decisions during plan implementation. The ecological monitoring program outlined in the strategy involves the collection of data on ecological indicators such as chlorophyll-a, water clarity, habitat assessments on river reaches and fish sampling. The strategy also recommends a public reporting regime for the WQIP.

Wallis Smiths Myall

3.9

Future investigation relating to the Farm Scale Action Plan[DG5]

Areas for investigation include riparian management, wetland management, groundcover management, farm infrastructure management, nutrient management and ways to encourage uptake of improved management practices. The findings from this research are applicable across all three catchments.

Wallis Smiths Myall

3.3.2

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Predicted ecological improvements resulting from management actions

Wallis Lake

Substantial reduction in chlorophyll-a concentrations would be achieved in the Pipers Bay

area with full implementation of the identified actions. Chlorophyll-a concentrations can

be reduced, on average, by 13% and up [DG6]to 26% for Pipers Bay; and, on average, by

3%, and up to 7% for [pt7]the upper, mid and lower estuary zones. Although substantial,

these changes do not reach the target 50% reduction in chlorophyll-a identified for Pipers

Bay, or the reductions identified for the upper and mid estuary.

Smiths Lake

The estimated feasible change in chlorophyll-a concentrations in Smiths Lake are in the

order of 3.6%. This result achieves the identified target of no decline in ecological

condition.

Myall Lakes

Reductions in chlorophyll-a concentrations of 2.4% would be achieved in the Bombah

Broadwater with full implementation of the management actions identified. Smaller

reductions would be achieved for the Boolambayte Lake (1.9%) and Myall Lake (1.6%).

Changes do not reach the 14% reduction identified as the long-term target for Bombah

Broadwater, but do achieve the target of no further decline for the Myall and

Boolambayte systems.

In conclusion, these changes do not fully achieve the identified long-term targets for

Pipers Bay, the upper and mid estuary of Wallis Lake, and Bombah Broadwater in the

Myall Lakes.

They are, however, an important step in moving towards these outcomes and are highly

important for the adoption of longer-term adaptive management. Importantly, the WQIP

recommends that there be no further decline in lake condition. This objective would be

achieved in all areas of Wallis, Myall and Smiths lakes through the implementation of the

WQIP.

Costs and future funding

Funding for the WQIP urban, rural and lake use actions is critical to the success of the

Plan. Sourcing funds is identified as one of the major challenges confronting the

organisations and community members who are committed to implementing WQIP

actions. The costs of funding the actions identified in the WQIP for each lake are

summarised below.

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Table 0.4. Summary of costs associated with implementing the Water Quality Improvement Plan after seven years.

Lake Total cost of WQIP implementation

Average annual cost over seven years

Wallis Lake $54,801,000 $7,687,000 Smiths Lake $1,221,200 $174,000 Myall Lakes $7,153,000 $954,000

Economic analysis undertaken as part of this project has shown that the benefit-cost ratio

for implementing the Wallis and Myall Lakes actions is economically viable. Smiths Lake,

however, did not demonstrate such a convincing response, with a benefit-cost ratio that

showed the Plan is difficult to justify on the grounds of economic efficiency alone. This

result is largely because Smiths Lake is currently in a High conservation value condition,

and predicted changes in water quality under the Plan actions do not lead to benefits that

are able to be feasibly estimated. Given the limitations of this analysis and the

environmental values identified by the local community, it is still recommended that the

WQIP actions be implemented for Smiths Lake.

Given the value of funding required to achieve the improvements in ecological condition

identified in this Plan, there would need to be a collective focus on seeking funding to

implement the WQIP through the development of a business plan. As funding becomes

available, the approach to implementation will need to be flexible and adaptable. The

potential sources of funds, their relative importance for implementing the plan and the

security of funding for the particular actions have been identified and are discussed within

the WQIP.

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CONTENTS

EXECUTIVE SUMMARY...................................................................................................................vii

CONTENTS.....................................................................................................................................xix

LIST OF APPENDICES ................................................................................................................. xxiii

LIST OF FIGURES ........................................................................................................................ xxiv

LIST OF TABLES.......................................................................................................................... xxix

GLOSSARY OF TERMS............................................................................................................... xxxv

ABBREVIATIONS ....................................................................................................................... xxxix

PART 1: PLANNING PROCESS – DEVELOPMENT OF THE WATER QUALITY IMPROVEMENT PLAN..........................................................................................1

1.1 INTRODUCTION ............................................................................................................................1 1.2 PROJECT BACKGROUND ................................................................................................................1 1.3 PROJECT AREA ............................................................................................................................1 1.4 PROJECT PURPOSE ......................................................................................................................3 1.5 PROCESS FOR DEVELOPING THE WATER QUALITY IMPROVEMENT PLAN.................................................4

1.5.1 Stakeholder input ...............................................................................................................5 1.5.1.1 Engagement of the Great Lakes CCI Advisory Committee.............................................6 1.5.1.2 Engaging key agencies................................................................................................6 1.5.1.3 Engaging with the general community and industry groups ...........................................6

1.5.2 Modelling ...........................................................................................................................7 1.5.2.1 Catchment investigation and modelling.........................................................................7 1.5.2.2 Estuary investigation and modelling..............................................................................8

1.5.3 Management planning and research ...................................................................................8 1.5.3.1 Rural management actions ..........................................................................................9 1.5.3.2 Rural stakeholder input ................................................................................................9 1.5.3.3 Urban and rural residential management actions ........................................................11 1.5.3.4 Urban and rural residential land stakeholder input.......................................................11 1.5.3.5 Lake use strategies....................................................................................................12 1.5.3.6 Management support actions to achieve water quality improvement actions (planning tools, management systems, regulations or incentive programs) .................12

1.5.4 A Decision Support System for water quality improvement.................................................14 1.5.4.1 Establishing Ecological Condition Targets ..................................................................14 1.5.4.2 Testing management scenarios and determining WQIP actions ..................................15

1.5.5 Water Quality Improvement Plan.......................................................................................16

PART 2: INDIVIDUAL LAKE WATER QUALITY IMPROVEMENT MANAGEMENT STRATEGIES ....19

2.1 DESCRIPTION OF PART 2.............................................................................................................19 2.2 WATER QUALITY ISSUES ..............................................................................................................19

2.2.1 Land-based impacts .........................................................................................................20 2.2.1.1 Ecosystem protection.................................................................................................20 2.2.1.2 Human exposure .......................................................................................................22

2.2.2 Water-based impacts........................................................................................................22 2.2.2.1 Ecosystem protection.................................................................................................22 2.2.2.2 Human exposure .......................................................................................................23

2.3 CATCHMENT AND ESTUARY PROCESSES .........................................................................................23 2.3.1 Catchment exports ...........................................................................................................24 2.3.2 In-stream processes .........................................................................................................27 2.3.3 Hydrodynamic processes..................................................................................................27

2.3.3.1 Coastal lakes.............................................................................................................27 2.3.3.2 River estuaries ..........................................................................................................28 2.3.3.3 Freshwater systems...................................................................................................30

2.3.4 Nutrient cycling and settling processes..............................................................................31 2.3.5 Modelling catchment and estuary processes in the Great Lakes CCI..................................33

2.3.5.1 Catchment exports.....................................................................................................34

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2.3.5.2 Hydrodynamics and ecological response....................................................................36 2.3.5.3 Model limitations, process representation and scale issues .........................................37 2.3.5.4 Estimates of model reliability and reasonable assurance statements ...........................38

2.4 WALLIS LAKE CATCHMENT DESCRIPTION ........................................................................................41 2.5 WALLIS LAKE – CURRENT STATE OF CATCHMENT AND ESTUARY HEALTH..............................................48

2.5.1 Wallis Lake segments and rivers.......................................................................................48 2.5.2 Synthesis of research for Wallis Lake................................................................................49

2.5.2.1 Previous research......................................................................................................49 2.5.2.2 CCI research .............................................................................................................50 2.5.2.3 Catchment management research..............................................................................51 2.5.2.4 Urban catchment management research ....................................................................53 2.5.2.5 Water quality in Wallis Lake .......................................................................................54 2.5.2.6 Ecology of Wallis Lake...............................................................................................58

2.5.3 Ecological condition..........................................................................................................62 2.5.3.1 Wallis Lake................................................................................................................66 2.5.3.2 Pipers Bay.................................................................................................................67 2.5.3.3 Lower Estuary ...........................................................................................................70 2.5.3.4 Middle Estuary...........................................................................................................71 2.5.3.5 Upper Estuary ...........................................................................................................71

2.5.4 Hydrodynamics ................................................................................................................72 2.5.5 Description of in-stream attenuation and remobilisation processes.....................................78 2.5.6 Catchment loads and pollutant generation.........................................................................78 2.5.7 Summary .........................................................................................................................81

2.6 WALLIS LAKE – SETTING TARGETS FOR WATER QUALITY MANAGEMENT................................................83 2.6.1 Using community values to help set targets.......................................................................83 2.6.2 Ecological Condition Targets and catchment loads ............................................................86

2.6.2.1 Wallis Lake Ecological Condition Targets ...................................................................88 2.6.2.2 Pipers Bay Ecological Condition Target ......................................................................89 2.6.2.3 Lower Estuary Ecological Condition Targets ...............................................................89 2.6.2.4 Upper Estuary Ecological Condition Target.................................................................90 2.6.2.5 Middle Estuary Ecological Condition Target ................................................................90 2.6.2.6 Feasible reductions in chlorophyll-a concentrations.....................................................91 2.6.2.7 Catchment loads........................................................................................................92

2.7 WALLIS LAKE – MANAGEMENT STRATEGIES TO ACHIEVE ECOLOGICAL CONDITION TARGETS...................94 2.7.1. Exploratory analysis of potential remediation and protection actions..................................94

2.7.1.1. Description of scenarios tested..................................................................................95 2.7.1.2 Catchment exports................................................................................................... 100 2.7.1.3 Estuary condition..................................................................................................... 112 2.7.1.4 Costs of modelled remediation actions ..................................................................... 115

2.7.2 Summary of recommended programs for protection, remediation and management support of Wallis Lake ............................................................................. 118 2.7.3. Summary of benefit-cost analysis results for Wallis Lake Plan......................................... 125

2.8 SMITHS LAKE CATCHMENT DESCRIPTION ...................................................................................... 129 2.9 SMITHS LAKE – CURRENT STATE OF CATCHMENT AND ESTUARY HEALTH............................................ 135

2.9.1 Smiths Lake segments and rivers.................................................................................... 135 2.9.2 Synthesis of research ..................................................................................................... 135

2.9.2.1 Previous research.................................................................................................... 135 2.9.2.2 CCI research ........................................................................................................... 135 2.9.2.3 Catchment management research............................................................................ 136 2.9.2.4 Urban catchment management research .................................................................. 136 2.9.2.5 Water quality in Smiths Lake.................................................................................... 136 2.9.2.6 Ecology of Smiths Lake............................................................................................ 137

2.9.3 Ecological condition........................................................................................................ 137 2.9.4 Hydrodynamics .............................................................................................................. 140 2.9.5 Description of in-stream attenuation and remobilisation processes................................... 142 2.9.6 Catchment loads and pollutant generation....................................................................... 142

2.10 SMITHS LAKE – SETTING TARGETS FOR WATER QUALITY MANAGEMENT............................................ 145 2.10.1 Using community values to help set targets ................................................................... 145 2.10.2 Ecological Condition Targets and catchment loads ........................................................ 148

2.11 SMITHS LAKE – MANAGEMENT STRATEGIES TO ACHIEVE ECOLOGICAL CONDITION TARGETS............... 151 2.11.1 Exploratory analysis of potential remediation and protection actions............................... 151

2.11.1.1 Description of remediation and protection actions ................................................... 152 2.11.1.2 Catchment exports................................................................................................. 156 2.11.1.3 Estuary condition ................................................................................................... 159 2.11.1.4 Costs of rural and urban remediation actions .......................................................... 159

2.11.2 Summary of recommended programs for protection, remediation and management support of Smiths Lake............................................................................ 160

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2.11.3. Summary of benefit-cost analysis results for the Smiths Lake Plan................................ 167 2.12 MYALL LAKES SYSTEM AND CATCHMENT DESCRIPTION.................................................................. 170 2.13. MYALL LAKES – CURRENT STATE OF CATCHMENT AND ESTUARY HEALTH ........................................ 175

2.13.1. Myall Lakes segments and rivers ................................................................................. 175 2.13.2. Synthesis of research .................................................................................................. 177

2.13.2.1 Previous research.................................................................................................. 177 2.13.2.2 CCI research ......................................................................................................... 178 2.13.2.3 Catchment management research.......................................................................... 179 2.13.2.4 Urban catchment management research ................................................................ 180 2.13.2.5 Water quality in the Myall Lakes ............................................................................. 178 2.13.2.6 Ecology in Myall Lakes........................................................................................... 184

2.13.3. Ecological condition ..................................................................................................... 185 2.13.4 Hydrodynamics............................................................................................................. 190 2.13.5 Description of in-stream attenuation and remobilisation processes ................................. 190 2.13.6. Catchment loads and pollutant generation .................................................................... 190 2.13.7 Summary ..................................................................................................................... 193

2.14 MYALL LAKES – SETTING TARGETS FOR WATER QUALITY MANAGEMENT ........................................... 195 2.14.1 Using community values to help set targets ................................................................... 195 2.14.2 Ecological Condition Targets and catchment loads ........................................................ 198

2.14.2.1 Myall Lake Ecological Condition Target .................................................................. 199 2.14.2.2 Boolambayte Lake Ecological Condition Target ...................................................... 200 2.14.2.3 Bombah Broadwater Ecological Condition Target.................................................... 200 2.14.2.4 Upper Myall River Ecological Condition Target........................................................ 200 2.14.2.5 Feasible reductions in chlorophyll-a concentrations................................................. 201 2.14.2.6 Catchment loads.................................................................................................... 202

2.15 MYALL LAKES – MANAGEMENT STRATEGIES TO ACHIEVE ECOLOGICAL CONDITION TARGETS .............. 203 2.15.1. Exploratory analysis of potential remediation and protection actions.............................. 204

2.15.1.1. Description of remediation and protection actions .................................................. 205 2.15.1.2 Catchment exports................................................................................................. 210 2.15.1.3 Estuary condition ................................................................................................... 221 2.15.1.4 Costs of modelled remediation actions ................................................................... 222

2.15.2 Summary of recommended programs for protection, remediation and management support of Myall Lakes............................................................................. 223 2.15.3. Summary of benefit-cost analysis results for Myall Lakes Plan ...................................... 229

PART 3 IMPLEMENTATION FRAMEWORK................................................................................... 233

3.1 DESCRIPTION OF PART 3........................................................................................................... 233 3.2 APPROACH TO ENGAGEMENT FOR IMPROVING WATER QUALITY ......................................................... 233

3.2.1 Partnerships................................................................................................................... 236 3.2.1.1 Responsible management of culturally significant landscapes ................................... 237

3.2.2 Learning for sustainability ............................................................................................... 238 3.2.2.1 Building leadership and organisational capacity for sustainability............................... 240

3.3 CATCHMENT MANAGEMENT IN RURAL AREAS ................................................................................. 241 3.3.1 Existing water quality management systems (rural).......................................................... 241

3.3.1.1 Plans....................................................................................................................... 241 3.3.1.2 Programs ................................................................................................................ 242 3.3.1.3 Development Assessment........................................................................................ 249

3.3.2 Strategy for implementing the Farm Scale Action Plan..................................................... 251 3.3.2.1 Recommended approach for implementing the WQIP in rural areas .......................... 252 3.3.2.2 Whole-farm planning................................................................................................ 253 3.3.2.3 Partnerships............................................................................................................ 255 3.3.2.4 Improved land use planning in rural areas ................................................................ 260 3.3.2.5 Farm Scale Action Plan............................................................................................ 261

3.3.3 Recommendations for management of unpaved roads .................................................... 280 3.4 CATCHMENT MANAGEMENT IN URBAN AREAS ................................................................................. 283

3.4.1 Summary of existing urban water quality management.................................................... 283 3.4.1.1 Planning response................................................................................................... 283 3.4.1.2 Onground projects ................................................................................................... 284 3.4.1.3 Education and awareness........................................................................................ 285

3.4.2 Future urban area management...................................................................................... 286 3.4.2.1 Targets for urban and dense rural residential development ....................................... 287 3.4.2.2 Planning controls for development............................................................................ 290 3.4.2.3 Development Control Plan provisions ....................................................................... 297 3.4.2.4 Integrated water cycle management ......................................................................... 299 3.4.2.5 Nutrient offset scheme............................................................................................. 300 3.4.2.6 Development Control processes............................................................................... 301 3.4.2.7 Managing construction sites..................................................................................... 301

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3.4.2.8 Managing established areas..................................................................................... 305 3.4.2.9 Rainwater tanks retrofitting program......................................................................... 310 3.4.2.10 Other programs for established urban and dense rural residential areas .................. 310 3.4.2.11 Other opportunities ................................................................................................ 316 3.4.2.12 Implementation strategy......................................................................................... 320

3.5 LAKE USE STRATEGIES .............................................................................................................. 324 3.5.1 Existing lake use management systems .......................................................................... 324

3.5.1.1 Boating activities...................................................................................................... 324 3.5.1.2 Aquaculture industry ................................................................................................ 326

3.5.2 Management recommendations for lake use ................................................................... 328 3.5.2.1 Boating impacts....................................................................................................... 328 3.5.2.2 Oyster aquaculture .................................................................................................. 330

3.6 INSTITUTIONAL ARRANGEMENTS FOR WATER QUALITY IMPROVEMENT................................................. 336 3.6.1 Implementation responsibilities ....................................................................................... 336

3.6.1.1 Great Lakes Council ................................................................................................ 337 3.6.1.2 Greater Taree City Council....................................................................................... 340 3.6.1.3 MidCoast Water....................................................................................................... 342 3.6.1.4 Hunter-Central Rivers Catchment Management Authority.......................................... 343 3.6.1.5 Department of Environment and Climate Change ..................................................... 344 3.6.1.6 Department of Planning ........................................................................................... 345 3.6.1.7 Department of Primary Industries (Agriculture).......................................................... 345 3.6.1.8 Other agencies’ WQIP actions.................................................................................. 346

3.6.2 Coordination responsibilities ........................................................................................... 350 3.6.2.1 CCI Project Advisory Committee .............................................................................. 350 3.6.2.2 Operational water cycle management agencies ........................................................ 351 3.6.2.3 Joint Action Plan......................................................................................................352 3.6.2.4 Aligning NRM and land use plans with the WQIP...................................................... 355

3.6.3 Way forward................................................................................................................... 362 3.6.3.1 CCI Advisory Committee responsibilities................................................................... 362 3.6.3.2 NRM coordination forums’ responsibilities ................................................................ 363 3.6.3.3 Operational water cycle managers’ responsibilities ................................................... 363

3.7 POLLUTION CONTROL SYSTEMS ................................................................................................. 364 3.7.1 Policing development consents....................................................................................... 364

3.7.1.1 Environmental Planning & Assessment Act 1979 ...................................................... 364 3.7.2 General pollution control ................................................................................................. 369

3.7.2.1 Protection of the Environment Operations Act 1997 .................................................. 369 3.7.3 Sewage discharge risks.................................................................................................. 371

3.7.3.1 GLC On-site Sewage Management Strategy ............................................................ 371 3.7.4 Erosion and sedimentation risks...................................................................................... 376

3.7.4.1 Introduction to legislation and policy ......................................................................... 376 3.7.4.2 Management practice .............................................................................................. 379 3.7.4.3 Recommendations................................................................................................... 383

3.7.5 Strategy for implementing recommendations ......................... Error! Bookmark not defined. 3.7.5.1 Operational commitments ........................................................................................ 384 3.7.5.2 Contributions to community debate........................................................................... 388

3.7.6 Summary ....................................................................................................................... 390 3.8 FINANCING THE WATER QUALITY IMPROVEMENT PLAN .........................ERROR! BOOKMARK NOT DEFINED. 3.9 ADAPTIVE MANAGEMENT STRATEGY .................................................ERROR! BOOKMARK NOT DEFINED.

3.9.1 Embracing uncertainty .......................................................... Error! Bookmark not defined. 3.9.2 Plan / do / review loops................................................................................................... 411

3.9.2.1 Measuring performance ................................................. Error! Bookmark not defined. 3.9.2.2 Review and public reporting ..................................................................................... 425 3.9.2.3 Implementation strategy................................................. Error! Bookmark not defined. 3.9.2.4 Research agenda .................................................................................................... 435

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LIST OF APPENDICES [pt8]

APPENDICES.........................................................................................................................433

APPENDIX 1 ENGAGEMENT STRATEGY REPORT .................................................................................441 APPENDIX 2 STATEMENTS OF JOINT INTENT......................................................................................471 APPENDIX 3 EXISTING ENVIRONMENTAL FLOW MANAGEMENT SYSTEMS..................................................489 APPENDIX 4 ISSUES IDENTIFIED BY THE COMMUNITY...........................................................................493 APPENDIX 5 ESTIMATES OF MODEL RELIABILITY AND MODELLING LIMITATIONS .........................................511 APPENDIX 6 CONTRIBUTIONS OF POLLUTANTS BY LAND USE IN INDIVIDUAL SUB-CATCHMENTS,

WALLIS LAKE .............................................................................................................535 APPENDIX 7 PRIORITY RESEARCH AND DEVELOPMENT ACTIVITIES .........................................................595 APPENDIX 8 BACKGROUND INFORMATION ON WALLIS LAKE AND CATCHMENT .........................................601 APPENDIX 9 AGRICULTURAL INDUSTRY PROFILES...............................................................................631 APPENDIX 10 ESTABLISHING TARGETS FOR INDICATORS OF ECOLOGICAL CONDITION .................................637 APPENDIX 11 CASE STUDIES FROM THE GREAT LAKES COASTAL CATCHMENTS

INITIATIVE PROJECT .....................................................................................................643 APPENDIX 12 SEASONAL VARIATION IN POLLUTANT LOADS FOR WALLIS AND MYALL LAKES .........................659 APPENDIX 13 ESTABLISHING THE FEASIBILITY OF THE WQIP SCENARIOS.................................................669 APPENDIX 14 WQIP SCENARIO DESCRIPTIONS FOR WALLIS LAKE ..........................................................671 APPENDIX 15 ECONOMIC VALUES (BENEFITS) OF WATER QUALITY IMPROVEMENTS IN THE

GREAT LAKES – DRAFT REPORT....................................................................................703 APPENDIX 16 BACKGROUND INFORMATION ON SMITHS LAKE AND CATCHMENT .........................................747 APPENDIX 17 WQIP SCENARIO DESCRIPTIONS FOR SMITHS LAKE..........................................................767 APPENDIX 18 BACKGROUND INFORMATION ON MYALL LAKES AND CATCHMENT.........................................783 APPENDIX 19 CONTRIBUTIONS OF POLLUTANTS BY LAND USE IN INDIVIDUAL SUB-CATCHMENTS,

MYALL LAKES.............................................................................................................809 APPENDIX 20 WQIP SCENARIO DESCRIPTIONS FOR MYALL LAKES .........................................................827 APPENDIX 21 DRINKING WATER STRATEGY FOR THE CRAWFORD RIVER ..................................................849 APPENDIX 22 PRINCIPLES OF LEARNING FOR SUSTAINABILITY ................................................................861 APPENDIX 23 BUILDING CONSUMMATE LEADERS FOR SUSTAINABILITY .....................................................867 APPENDIX 24 LANDHOLDER COMMENTS AND PRACTITIONER NOTES REGARDING

FARM SCALE ACTION PLAN ..........................................................................................869 APPENDIX 25 FARM-SCALE WATER QUALITY ASSESSMENT AND PLANNING TOOL........................................897 APPENDIX 26 CATCHMENT MANAGEMENT PRACTITIONER NOTES FOR

ENGAGING WITH LANDHOLDERS .....................................................................................899 APPENDIX 27 DESIGN POINTS FOR ON-GROUND WORKS

(RURAL MANAGEMENT PRACTICES) (DRAFT) ....................................................................903 APPENDIX 28 URBAN EDUCATION PROGRAM PLAN ...............................................................................941 APPENDIX 29 PLANS AND STRATEGIES IN THE GREAT LAKES REGION, AND THE AREAS IN WHICH

THEY SHOULD BE REVIEWED FOR CONSISTENCY WITH THE WQIP........................................949 APPENDIX 30 ECOLOGICAL MONITORING OF THE WATER QUALITY IMPROVEMENT PLAN .............................961

BIBLIOGRAPHY .....................................................................................................................973

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LIST OF FIGURES Figure 1.3.1. The Great Lakes Coastal Catchments Initiative project area, showing the

Myall Lakes, Smiths Lake and Wallis Lake catchments, and local government area boundaries...............................................................................................................2

Figure 1.4.1. Stakeholders engaged in developing and reviewing the WQIP for Wallis and Smiths lakes, and the Myall Lakes system ................................................................4

Figure 1.5.1. Components and process of the Great Lakes CCI project towards the development of the WQIP......................................................................5

Figure 2.3.1. Conceptual diagram showing the difference between the natural water cycle and a modified urban water cycle............................................................................24

Figure 2.3.2. A conceptual diagram of generation of diffuse sources of pollutants and transport into streams / rivers via surface and subsurface flows..............................................25

Figure 2.3.3. Zones in a coastal lake: Lake margin and central basin. ..........................................28 Figure 2.3.4. Distinct zones in a river estuary, defined by the interaction between fresh water

and salt water in the water profile: Tidal River, Upper Estuary, Middle Estuary and Lower Estuary .................................................................................................29

Figure 2.3.5. Distinct zones in a river estuary of tidal river, upper estuary, middle estuary and lower estuary – as defined through estuary depth, width, turbidity, salinity and algae...............................................................................................................30

Figure 2.3.6. A conceptual diagram of nutrient cycling processes in coastal lakes and coastal river estuaries ............................................................................................31

Figure 2.3.7. Scientific modelling of catchment and estuary processes were used to construct the data base for the Great Lakes CCI Decision Support System (DSS) and, together with outputs from management planning and research projects, guided the DSS functions .......................................................................................34

Figure 2.4.1. The seven primary sub-catchments of Wallis Lake Catchment.................................42 Figure 2.4.2. Modelled land use categories in the Wallis Lake Catchment ....................................44 Figure 2.5.1. Zones in the Wallis Lake estuary used for modelling and analysis,

and reporting on condition in this Plan.....................................................................49 Figure 2.5.2. Mean chlorophyll-a concentrations (g/L) recorded in Wallis Lake estuary

by DECC Waters and Catchment Science in 2006/07..............................................57 Figure 2.5.3. Estuarine sponges and diverse benthic algae in Wallis Lake....................................59 Figure 2.5.4. Biodiversity in Wallis Lake ......................................................................................60 Figure 2.5.5. Current ecological condition of coastal lake water at south Wallis Lake

and Coomba Bay ...................................................................................................64 Figure 2.5.6. Current ecological condition of the river estuaries in Wallis Lake..............................65 Figure 2.5.7. An erosion gully feeding into Coomba Bay, Wallis Lake...........................................66 Figure 2.5.8. Coomba Bay, Wallis Lake, 7 June 2007 showing turbid (dirty) water,

mud area and absence of seagrass ........................................................................67 Figure 2.5.9. Forster sub-catchments draining into Wallis Lake....................................................68 Figure 2.5.10. Excessive growth of macroalgae over seagrass beds in Pipers Creek, Wallis Lake ..69 Figure 2.5.11. TN concentrations within the Lower Estuary and Wallis Lake for a large event

(21 October 2004) and a dry period (26 November 2002) ........................................73 Figure 2.5.12. Wallis Lake and the complex of islands that restrict mixing of the waters

in Wallis Lake with those of Southern Wallis Lake and the Lower Estuary ................75 Figure 2.5.13. Simulated TN concentrations in the Wallis Lake system for 7, 10, 13, 15

and 18 May 2001 ...................................................................................................76 Figure 2.5.14. Relative contribution of land use activities to pollutants and area in the

whole Wallis Lake catchment..................................................................................80 Figure 2.6.1. Process for developing water quality targets for Wallis, Smiths and Myall lakes........83 Figure 2.7.1. Percentage change in Wallis Lake catchment exports of TN, TP and TSS

both with (WQIP) and without (No Plan) implementation of the Water Quality Improvement Plan................................................................................................ 101

Figure 2.7.2. Relative modelled impact of expanded remediation actions for the whole Wallis Lake catchment with implementation of the WQIP ............................. 104

Figure 2.7.3. Relative modelled impact of expanded remediation actions for the Wallamba River sub-catchment of the Wallis Lake system, with implementation of the WQIP......................................................................................................... 105

Figure 2.7.4. Relative modelled impact of expanded remediation actions for the Wang Wauk River sub-catchment of the Wallis Lake system with implementation of the WQIP......................................................................................................... 106

Figure 2.7.5. Relative modelled impact of expanded remediation actions for the Coolongolook River sub-catchment of the Wallis Lake system with implementation of the WQIP................................................................................. 107

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Figure 2.7.6. Relative modelled impact of expanded remediation actions for the Wallingat River sub-catchment of the Wallis Lake system with implementation of the WQIP......................................................................................................... 108

Figure 2.7.7. Relative modelled impact of expanded remediation actions for the Lower Estuary sub-catchment of the Wallis Lake system with implementation of the WQIP........... 109

Figure 2.7.8. Relative modelled impact of expanded remediation actions for the Wallis Lake (southern and western) sub-catchment of the Wallis Lake system with implementation of the WQIP................................................................................. 110

Figure 2.7.9. Relative modelled impact of expanded remediation actions for the Wallis Lake (Forster) sub-catchment groups of the Wallis Lake system with implementation of the WQIP......................................................................................................... 111

Figure 2.7.10. Percentage change in chlorophyll-a achieved in the Upper Estuary of Wallamba River in the Wallis Lake system ............................................................ 113

Figure 2.7.11. Percentage change in chlorophyll-a achieved in the Lower Estuary of the Wallis Lake system......................................................................................... 113

Figure 2.7.12. Percentage change in chlorophyll-a achieved in Pipers Bay of the Wallis Lake system .............................................................................................. 114

Figure 2.7.13. Percentage change in chlorophyll-a achieved in the Middle Estuary of the Wallamba, Coolongolook and Wang Wauk rivers in Wallis Lake ............................ 114

Figure 2.7.14. Percentage change in chlorophyll-a achieved in Wallis Lake.................................. 115 Figure 2.7.15. Cumulative costs of modelled rural remediation actions in the

Wallis Lake catchment.......................................................................................... 116 Figure 2.7.16. Cumulative costs of urban remediation actions in the Wallis Lake catchment ......... 117 Figure 2.8.1. Smiths Lake catchment ........................................................................................ 132 Figure 2.8.2. Modelled land uses in the Smiths Lake catchment................................................. 133 Figure 2.9.1. Current ecological condition of the coastal lake water body of Smiths Lake ............ 139 Figure 2.9.2. Response of Smiths Lake to an entrance opening................................................. 141 Figure 2.9.3. Relative contributions of land use activities to pollutants (TN, TP) and sediments

(TSS) in the Smiths Lake catchment ..................................................................... 144 Figure 2.10.1. Process for developing water quality targets for Wallis, Smiths and Myall lakes...... 145 Figure 2.11.1. Percentage change in Smiths Lake catchment exports of TN, TP and TSS,

both with (WQIP) and without (No Plan) implementation of the Water Quality Improvement Plan................................................................................................ 157

Figure 2.11.2. Relative modelled impact of expanded remediation actions for the Smiths Lake catchment with implementation of the WQIP ......................................................... 158

Figure 2.11.3. Percentage change in chlorophyll-a concentrations in Smiths Lake, both with (WQIP) and without (No Plan) implementation of the Water Quality Improvement Plan................................................................................................ 159

Figure 2.11.4. Cumulative costs of Plan actions in Smiths Lake ................................................... 160 Figure 2.12.1. The Myall Lakes sub-catchments and major tributaries.......................................... 172 Figure 2.12.2. Modelled land use categories in the Myall Lakes catchment .................................. 173 Figure 2.13.1. Zones in Myall Lakes system used for modelling and analysis,

and reporting on condition in this Plan................................................................... 176 Figure 2.13.2. Mean chlorophyll-a concentrations (g/L) calculated from DNR data

(1999 to 2002), NPWS / DNR Data (2003 to 2005) and DECC Waters and Catchment Science data (2006/07)..................................................... 183

Figure 2.13.3. Current ecological condition of the Myall Lakes water bodies of Myall Lake, Boolambayte Lake and Bombah Broadwater......................................................... 188

Figure 2.13.4. Current ecological condition of the Upper Myall River estuary................................ 189 Figure 2.13.5. Relative contributions of land use activities to pollutants (TN, TP) and sediments

(TSS) in the Myall Lakes catchment...................................................................... 192 Figure 2.14.1. Process for developing water quality targets for Wallis, Smiths and Myall lakes...... 195 Figure 2.15.1. Percentage change in catchment exports of TN, TP and TSS in the

Myall Lakes under the No Plan and WQIP alternative futures................................. 210 Figure 2.15.2. Relative modelled impact of expanded remediation actions for the whole

Myall Lakes catchment with implementation of the WQIP ...................................... 214 Figure 2.15.3. Relative modelled impact of expanded remediation actions for the

Myall Lake sub-catchment with implementation of the WQIP ................................. 215 Figure 2.15.4. Relative modelled impact of expanded remediation actions for the

Boolambayte Lake sub-catchment with implementation of the WQIP...................... 216 Figure 2.15.5. Relative modelled impact of expanded remediation actions for the

Upper Myall River sub-catchment with implementation of the WQIP....................... 217 Figure 2.15.6. Relative modelled impact of expanded remediation actions for the

Crawford River sub-catchment with implementation of the WQIP........................... 218 Figure 2.15.7. Relative modelled impact of expanded remediation actions for the Bombah

Broadwater sub-catchment with implementation of the WQIP ................................ 219

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Figure 2.15.8. Relative modelled impact of expanded remediation actions for Lower Myall River sub-catchment with implementation of the WQIP....................... 220

Figure 2.15.9. Percentage change in chlorophyll-a achieved in the Myall Lakes under the No Plan and WQIP alternative futures................................................................... 221

Figure 2.15.10. Cumulative costs of potential rural WQIP actions................................................... 222 Figure 3.4.1. Comparison of loads from various land use scenarios ........................................... 288 Figure 3.4.2. Single dwelling to two lots – Unmitigated and ‘Deemed to Comply’ solution............ 298 Figure 3.4.3. Proposed release areas in the Forster region........................................................ 303 Figure 3.4.4. Proposed WSUD retrofitting locations ................................................................... 304 Figure 3.4.5. Dense urban area street tree bioretention ............................................................. 306 Figure 3.4.6. Street tree bioretention ‘pods’ ............................................................................... 307 Figure 3.4.7. Diagram of pod retrofitting into existing kerb.......................................................... 307 Figure 3.4.8. A retrofitting proposal for Pipers Creek catchment ................................................. 308 Figure 3.4.9. Smiths Lake sub-catchments and release areas.................................................... 309 Figure 3.7.1. Erosion and sedimentation control efficiency......................................................... 382 Figure 3.9.1. Adaptive management activities............................................................................ 412 Figure 3.9.2. Fundamental plan / do / review loops in the WQIP................................................. 414 Figure 3.9.3. The new Local Government Planning Framework.................................................. 427 Figure A1.1. Landholders filling in surveys at workshops........................................................... 453 Figure A1.2. Landholders attending research and feedback workshop at Bunyah ...................... 453 Figure A1.3. Advisory Committee attending field visit and meeting ............................................ 455 Figure A1.4. Great Lakes Council, Greater Taree City Council, Catchment Management

Authority and MidCoast Water signing Statements of Joint Intent........................... 460 Figure A3.1. Example flow duration curve for an unregulated river............................................. 489 Figure A5.1. Calibration points within the Myall Lakes and Wallis Lake catchments.................... 517 Figure A5.2. Observed vs modelled estimates of runoff from the Bombah Broadwater,

Coolongolook, Wallamba and Wang Wauk............................................................ 520 Figure A6.1. Location of sub-catchments of Wallis Lake............................................................ 535 Figure A6.2. The Wallamba River sub-catchments.................................................................... 540 Figure A6.3. Relative contribution of land use activities to pollutants and area in the

Wallamba River sub-catchments........................................................................... 543 Figure A6.4. The Wang Wauk River sub-catchments ................................................................ 545 Figure A6.5. Relative contribution of land use activities to pollutants and area in the

Wang Wauk River sub-catchments ....................................................................... 547 Figure A6.6. The Coolongolook River sub-catchments .............................................................. 549 Figure A6.7. Relative contribution of land use activities to pollutants and area in the

Coolongolook River sub-catchments..................................................................... 551 Figure A6.8. The Wallingat River sub-catchments..................................................................... 553 Figure A6.9. Relative contribution of land use activities to pollutants and area in the

Wallingat River sub-catchments............................................................................ 554 Figure A6.10. The Lower Estuary sub-catchments...................................................................... 556 Figure A6.11 Relative contribution of land use activities to pollutants and area in the

Lower River Estuary sub-catchments.................................................................... 558 Figure A6.12. The southern and western sub-catchments of Wallis Lake..................................... 560 Figure A6.13. Relative contribution of land use activities to pollutants and area in the

southern and western sub-catchments of Wallis Lake............................................ 562 Figure A6.14. The Wallis Lake–Forster sub-catchments.............................................................. 564 Figure A6.15. Relative contribution of land use activities to pollutants and area in the

Forster sub-catchments of Wallis Lake.................................................................. 566 Figure A6.16. Pollutants and areas by land use, Upper Wallamba River (HS1a) .......................... 567 Figure A6.17. Pollutants and areas by land use, Firefly River (HS1b) .......................................... 568 Figure A6.18. Pollutants and areas by land use, Khoribakh Creek (HS1c) ................................... 569 Figure A6.19. Pollutants and areas by land use, Candoormakh and Pipeclay Creeks (HS1d)....... 570 Figure A6.20. Pollutants and areas by land use, Bungwahl and Darawakh Creeks (HS2)............. 571 Figure A6.21. Pollutants and areas by land use, Minimbah and Tuncurry (HS3)........................... 572 Figure A6.22. Pollutants and areas by land use, Wallingat River (HS4)........................................ 573 Figure A6.23. Pollutants and areas by land use, Coomba Creek (HS5)........................................ 574 Figure A6.24. Pollutants and areas by land use, Duck Creek (HS6)............................................. 575 Figure A6.25. Pollutants and areas by land use, Bunyah Creek (HS7a)....................................... 576 Figure A6.26. Pollutants and areas by land use, Upper Wang Wauk River (HS7b)....................... 577 Figure A6.27. Pollutants and areas by land use, Lower Wang Wauk River (HS7c) ....................... 578 Figure A6.28. Pollutants and areas by land use, Coolongolook Estuary Reach (HS8) .................. 579 Figure A6.29. Pollutants and areas by land use, Cureeki Creek (HS9a)....................................... 580 Figure A6.30. Pollutants and areas by land use, Upper Coolongolook River (HS9b)..................... 581 Figure A6.31. Pollutants and areas by land use, Lower Coolongolook River (HS9c)..................... 582 Figure A6.32. Pollutants and areas by land use, Beaky Bay (HS10) ............................................ 583 Figure A6.33. Pollutants and areas by land use, Coomba / Wallis Island (HS11).......................... 584

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Figure A6.34. Pollutants and areas by land use, Coomba Bay (HS12)......................................... 585 Figure A6.35. Pollutants and areas by land use, Whoota / Yarric (HS13) ..................................... 586 Figure A6.36. Pollutants and areas by land use, Pacific Palms (HS14) ........................................ 587 Figure A6.37. Pollutants and areas by land use, Booti Booti (HS15) ............................................ 588 Figure A6.38. Pollutants and areas by land use, Green Point (HS16) .......................................... 589 Figure A6.39. Pollutants and areas by land use, Pipers Bay (Cape Hawke) (HS17) ..................... 590 Figure A6.40. Pollutants and areas by land use, Pipers Creek (South Forster) (HS18) ................. 591 Figure A6.41. Pollutants and areas by land use, Big Island (HS19).............................................. 592 Figure A6.42. Pollutants and areas by land use, Forster (HS20).................................................. 593 Figure A8.1. Location of Wallis Lake within the Great Lakes in the Hunter-Central Rivers

region, just north of the Myall Lakes and Smiths Lake catchments ......................... 603 Figure A8.2. Local government jurisdictions within the Wallis Lake catchment ........................... 604 Figure A8.3. Land uses in the Wallis Lake catchment................................................................ 609 Figure A8.4. Aerial image of the Wallis Lake entrance, showing the major urban settlements

of Forster and Tuncurry........................................................................................ 613 Figure A8.5. Macrophyte vegetation in Wallis Lake catchment................................................... 615 Figure A10.1. Range of data from a high conservation value system and a disturbed system....... 639 Figure A11.1. Diagram showing how the maximum depth that seagrass can survive

at is directly related to the water clarity.................................................................. 644 Figure A11.2. Fate of pollution from Wallamba River................................................................... 645 Figure A11.3. Fate of pollution from Wang Wauk River ............................................................... 646 Figure A11.4. Map of Wallis Lake............................................................................................... 647 Figure A11.5(a). Coomba Bay 7 June 2007, showing turbid (dirty) water, mud area and

absence of seagrass ............................................................................................ 649 Figure A11.5(b). Google Earth image of Coomba Bay showing turbid (dirty) water and

absence of seagrass ............................................................................................ 649 Figure A11.6(a). Coomba Bay erosion gully.................................................................................... 651 Figure A11.6(b). Location of Coomba Bay erosion gully remediation works...................................... 651 Figure A11.7. Land-based muds have smothered seagrass over an area of at least 2.5 ha

along the shore of Coomba Bay............................................................................ 652 Figure A11.8. Excessive growth of macroalgae over seagrass beds in Pipers Creek.................... 653 Figure A11.9. Healthy clear-water ecosystems around Earps Island, showing

rare estuarine sponges and diverse benthic algae................................................. 655 Figure A12.1. Average monthly temperature and precipitation in the Great Lakes region.............. 660 Figure A12.2. Mean runoff volume and TN, TP and TSS loads for the Wallamba River

calibrated sub-catchment...................................................................................... 661 Figure A12.3. Mean runoff volume and TN, TP and TSS loads for the Wang Wauk River

calibrated sub-catchment...................................................................................... 662 Figure A12.4. Mean runoff volume and TN, TP and TSS loads for the Coolongolook River

calibrated sub-catchment...................................................................................... 663 Figure A12.5. Mean runoff volume and TN, TP and TSS loads for the Smiths Lake

calibrated sub-catchment...................................................................................... 665 Figure A12.6. Mean runoff volume and TN, TP and TSS loads for the Bulahdelah

calibrated sub-catchment...................................................................................... 667 Figure A14.1. Interpolated effect of management programs for groundcover................................ 681 Figure A14.2. Sub-catchments of the Wallis and Smiths lakes, showing DSS

sub-catchment codes ........................................................................................... 691 Figure A15.1. Total Economic Value .......................................................................................... 707 Figure A15.2. Measurement of Economic Values over Time With and

Without a Policy Outcome .................................................................................... 710 Figure A15.3. Catchment Exports for Wallis Lake With and Without the WQIP............................. 722 Figure A15.4. Catchment Exports for Smiths Lake With and Without the WQIP ........................... 729 Figure A15.5. Catchment Exports for Myall Lake With and Without the WQIP.............................. 734 Figure A15.6. Catchment Exports for Myall Lake With and Without the Drinking Water Strategy

for the Crawford Catchment.................................................................................. 735 Figure A16.1. Location of Smiths Lake and its catchment relative to Wallis Lake and Myall Lake.. 749 Figure A16.2. Distribution and extent of land use activities within the Smiths Lake catchment ...... 754 Figure A16.3. Smiths Lake is contained within the Port Stephens–Great Lakes Marine Park ........ 757 Figure A16.4. Seagrass habitat within Smiths Lake..................................................................... 758 Figure A17.1. Interpolated effect of management programs for groundcover................................ 771 Figure A18.1. Location of the Myall Lakes and its catchment relative to Wallis Lake..................... 785 Figure A18.2. Distribution and extent of land use activities within the Myall Lakes catchment ....... 789 Figure A18.3. The water bodies of Myall Lakes, Myall River and Crawford River

are contained within the Port Stephens–Great Lakes Marine Park ......................... 793 Figure A19.1. Sub-catchments in the Myall Lakes catchment ...................................................... 813 Figure A19.2. Relative contribution of land use activities to pollutants and area in

Myall Lake sub-catchment .................................................................................... 815

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Figure A19.3. Relative contribution of land use activities to pollutants and area in Boolambayte Creek sub-catchment ...................................................................... 817

Figure A19.4. Relative contribution of land use activities to pollutants and area in Upper Myall River sub-catchment ......................................................................... 819

Figure A19.5. Relative contribution of land use activities to pollutants and area in Crawford River sub-catchment.............................................................................. 821

Figure A19.6. Relative contribution of land use activities to pollutants and area in Bombah Broadwater sub-catchment ..................................................................... 823

Figure A19.7. Relative contribution of land use activities to pollutants and area in Lower Myall River sub-catchment ......................................................................... 825

Figure A20.1. Interpolated effect of management programs for groundcover................................ 837 Figure A21.1. Crawford River – Percentage change in catchment exports of TN, TP and

TSS with (WQIP) implementation of the Water Quality Improvement Plan.............. 851 Figure A21.2. Crawford River – Relative impact of component remediation actions for the

whole catchment .................................................................................................. 851 Figure A21.3. Percentage change in chlorophyll-a achieved in the Myall Lakes due to the

potential Crawford River Drinking Water plan actions ............................................ 852 Figure A21.4. Cumulative costs of potential Crawford WQIP actions............................................ 853

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LIST OF TABLES Table 0.1. Stakeholder engagement in WQIP development ....................................................viii Table 0.2. Remediation actions proposed in the Water Quality Improvement Plan. ...................xiii Table 0.3. Protection actions proposed in the Water Quality Improvement Plan........................xiv Table 0.4. Summary of costs associated with implementing the Water Quality Improvement Plan after seven years. ...............................................xvii Table 1.5.1. Key steps for establishing ecological condition targets and WQIP actions for the Wallis, Smiths and Myall lakes systems. .................................................................15 Table 2.3.1. Forms of nitrogen and phosphorus that can be found in coastal lakes

and river estuary waters, and their likely short-term bioavailability to stimulate algal growth ...........................................................................................................32

Table 2.3.2. Land use classes used in the rural land use model AnnAGNPS and as represented in combined classes in the Great Lakes CCI DSS. ....................35

Table 2.3.3. Modelled hydrodynamic features of the Wallis, Smiths and Myall lakes ....................36 Table 2.5.1. Pollutant removal by Kularoo Drive Wetlands, urban catchment management

in the Wallis Lake catchment ..................................................................................53 Table 2.5.2. Impact of Wallis Lake sub-catchment group pollutant exports on

ecological condition in the Wallis Lake estuary zones ..............................................61 Table 2.5.3. Average chlorophyll-a concentrations (μg/L) recorded in

Southern Wallis Lake and Coomba Bay ..................................................................67 Table 2.5.4. Average chlorophyll-a concentrations (μg/L) recorded in

Pipers Creek and Pipers Bay, Wallis Lake...............................................................70 Table 2.5.5. Average chlorophyll-a concentrations (μg/L) recorded in

the lower estuary water bodies of Wallis Lake .........................................................70 Table 2.5.6. Average chlorophyll-a concentrations (μg/L) recorded in

the middle estuaries of Wallis Lake.........................................................................71 Table 2.5.7. Average chlorophyll-a concentrations (μg/L) recorded in

the upper estuaries of the Wallis Lake system.........................................................72 Table 2.5.8. Area and pollutant exports from Wallis Lake sub-catchment groups.........................79 Table 2.6.2. Environmental values and uses given by stakeholders and the community

for Wallis Lake Estuary...........................................................................................84 Table 2.6.1. Ecological condition targets using chlorophyll-a concentrations, and estimates of

feasible change for Wallis Lake estuary zones ........................................................92 Table 2.6.2. Feasible catchment load reductions in Wallis Lake that achieve predicted change

in chlorophyll-a concentrations................................................................................93 Table 2.7.1. Remediation actions modelled for rural areas of the Wallis Lake Catchment.............96 Table 2.7.2. Remediation actions modelled for urban areas in the Wallis Lake catchment............97 Table 2.7.3. Protection actions considered for the Wallis Lake catchment ...................................97 Table 2.7.4. Scenario trajectories with (WQIP) and without (No Plan) the implementation

of the Water Quality Improvement Plan for the Wallis Lake catchment ................... 100 Table 2.7.5. Percentage change in loads from the modelled Wallis Lake sub-catchment

groups achieved after seven years implementation of the WQIP............................ 102 Table 2.7.6. Cost ($) per unit of load controlled by modelled rural remediation actions applied

across the Wallis Lake catchment......................................................................... 116 Table 2.7.7. Cost ($) per unit of load controlled by urban actions applied across the

Wallis Lake catchment.......................................................................................... 118 Table 2.7.8. Summary of recommended programs in the Wallis Lake catchment: Protection,

remediation and management support .................................................................. 119 Table 2.7.9. Summary of total costs at seven years of remediation, protection and management

support actions in the Wallis Lake catchment as recommended by the Plan........... 124 Table 2.7.10. Costs and benefits for the Wallis Lake management actions.................................. 125 Table 2.7.11. Wallis Lake WQIP benefit-cost ratio of individual actions ....................................... 126 Table 2.9.1. Average chlorophyll-a concentrations (μg/L) and turbidity (NTU) recorded in

Smiths Lake......................................................................................................... 140 Table 2.9.2. Area (ha) and nitrogen (kg), phosphorus (kg) and sediment (tonnes) loads for

Smiths Lake sub-catchments................................................................................ 142 Table 2.10.1. Environmental values and uses given by stakeholders and the community for

Smiths Lake......................................................................................................... 146 Table 2.10.2. Ecological Condition Target for Smiths Lake and the feasible reduction in

chlorophyll-a concentrations ................................................................................. 150 Table 2.10.3. Feasible catchment load reductions in Smiths Lake that achieve predicted

change in chlorophyll-a concentrations ................................................................. 150 Table 2.11.1. Remediation actions modelled for rural areas of the Smiths Lake catchment. ......... 153 Table 2.11.2. Remediation actions modelled for urban areas in the Smiths Lake catchment. ....... 154

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Table 2.11.3. Protection actions considered for the Smiths Lake catchment................................ 154 Table 2.11.4. Scenario trajectories with (WQIP) and without (No Plan) the implementation

of the Water Quality Improvement Plan for the Smiths Lake catchment.................. 156 Table 2.11.5. Cost ($) per unit of load controlled by modelled remediation actions

applied across the Smiths Lake catchment............................................................ 160 Table 2.11.6. Summary of recommended programs in the Smiths Lake catchment:

Protection, remediation and management support................................................. 162 Table 2.11.7. Summary of total costs at seven years of remediation, protection and management

support actions for Smiths Lake catchment as recommended by the Plan.............. 166 Table 2.11.8. Costs and benefits for the Smiths Lake management actions................................. 167 Table 2.11.9. Smiths Lake WQIP benefit-cost ratio of individual actions...................................... 168 Table 2.13.1. Average chlorophyll-a concentrations (μg/L) recorded in the Myall Lakes ............... 187 Table 2.13.2. Area and pollutant exports from the Myall Lakes sub-catchments

(estimated using the DSS).................................................................................... 191 Table 2.14.1. Environmental values and uses given by stakeholders and community

for Myall Lakes..................................................................................................... 196 Table 2.14.2. Ecological Condition Targets and predicted reduction in chlorophyll-a

concentrations with implementation of the WQIP in the Myall Lakes....................... 202 Table 2.14.3. Predicted catchment load reductions for the Myall Lakes system following

implementation of the WQIP................................................................................. 203 Table 2.15.1. Remediation actions modelled for rural areas of the Myall Lakes catchment........... 205 Table 2.15.2. Protection actions considered for the Myall Lakes catchment................................. 207 Table 2.15.3. Scenario trajectories with (WQIP) and without (No Plan) the implementation

of the Water Quality Improvement Plan................................................................. 209 Table 2.15.4. Percentage change in loads from the modelled sub-catchments and the whole

Myall Lakes catchment achieved after seven years implementation of the WQIP.... 211 Table 2.15.5. Cost ($) per unit of load controlled by modelled rural remediation actions applied

across the Myall Lakes catchment ........................................................................ 223 Table 2.15.6. Summary of recommended programs in the Myall Lakes: Protection,

remediation and management support .................................................................. 224 Table 2.15.7. Summary of total costs of protection, remediation and management

support options recommended for the Myall Lakes at seven years......................... 228 Table 2.15.8. Costs and benefits for the Myall Lakes management actions ................................. 229 Table 2.15.9. Myall Lakes WQIP benefit-cost ratio of individual actions....................................... 230 Table 3.1.1. Great Lakes Council’s commitment to the levels of engagement in this strategy ..... 235 Table 3.3.1. Summary of Current rural programs that deliver water quality outcomes ................ 244 Table 3.3.2. Farm Scale Action Plan........................................................................................ 261 Table 3.3.3. Action plan for rural road management ................................................................. 281 Table 3.4.1. Quantitative definitions of catchment water quality targets ..................................... 288 Table 3.4.2. Targets for urban and dense rural residential land development............................. 289 Table 3.4.3. Proposed Development Control Plan provisions.................................................... 296 Table 3.4.4. Redevelopment scenario results – percentage change from existing case.............. 298 Table 3.4.5. Example Integrated Water Cycle Management Objectives..................................... 299 Table 3.4.6. Improvements in pollutant loads to Pipers Creek and Pipers Bay that can be

achieved with a substantial drainage system retrofitting program ........................... 308 Table 3.4.7. Improvements in pollutant loads to Smiths Lake that can be achieved with a

substantial drainage system retrofitting program.................................................... 309 Table 3.4.8. Recommendations for engagement and learning programs

for urban stakeholders.......................................................................................... 313 Table 3.4.9. Implementation strategy for urban and dense rural residential areas ...................... 321 Table 3.5.1. Implementation strategy – Recommended actions to manage the water quality

impacts of lake uses............................................................................................. 332 Table 3.6.1. Draft Joint Action Plan for the Great Lakes WQIP.................................................. 353 Table 3.6.2. Integration of the Water Quality Improvement Plan and MidCoast Water’s

Sustainable Water Cycle Management Strategy.................................................... 358 Table 3.6.3. SoJI partners’ plans that need to be reviewed for alignment with the WQIP............ 361 Table 3.7.1. Recommendations to improve pollution control systems ........................................ 384 Table 3.7.2. Contributions to community debate about pollution control..................................... 388 Table 3.8.1. Possible sources of funds for the WQIP ................................................................ 394 Table 3.8.2. Options for resourcing programs........................................................................... 399 Table 3.9.1. Working with key uncertainties.............................................................................. 404 Table 3.9.2(a). Operational and output measures by program....................................................... 415 Table 3.9.2(b). Ecological and outcome measures by program ..................................................... 418 Table 3.9.3. Implementation strategy for the adaptive management program ............................ 429 Table A1.1. Great Lakes Council’s commitment to the levels of engagement in this strategy ..... 443 Table A1.2. Engagement opportunities in the CCI Project ........................................................ 448

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Table A1.3. Evaluation techniques for engagement strategy objectives and associated measures of success .......................................................................... 462

Table A4.1. Wallis Lake issues................................................................................................ 494 Table A4.2. Smiths Lake issues .............................................................................................. 501 Table A4.3. Myall Lakes issues ............................................................................................... 504 Table A5.1. Model development for the Great Lakes CCI project.............................................. 511 Table A5.2. Summary of AnnAGNPS model components......................................................... 513 Table A5.3. Summary of data used to develop and test the AnnAGNPS models for the

Great Lakes catchments....................................................................................... 514 Table A5.4. A comparison of observed (O) and modelled (M) estimates of total event runoff

volume, total nitrogen (TN), total phosphorus (TP) and total suspended solids (TSS) between July and December 2006.............................................................. 519

Table A5.5. Precision of model predictions given by the coefficients of efficiency proposed by Nash and Futcliffe (1970).................................................................. 521

Table A5.6. A comparison of annual nutrient and sediment exports generated by AnnAGNPS and an Australian-based model (E2) .................................................. 522

Table A5.7. Summary of lake estuary models.......................................................................... 525 Table A5.8. Defining ecological response in the Great Lakes ................................................... 527 Table A5.9. Sources of uncertainty in the outputs from the DSS, and the catchment export

and estuary models.............................................................................................. 530 Table A5.10. Representing scales and processes in the Great Lakes CCI modelling................... 533 Table A6.1. Sub-catchments of Wallis Lake............................................................................. 536 Table A6.2. Land use classes represented in the Great Lakes CCI DSS................................... 537 Table A6.3. Area and pollutant exports from the Wallamba River sub-catchments .................... 542 Table A6.4. Percentage area of target and non-target land in the Wallamba River

sub-catchments, and the amount of total loads sourced from these lands............... 542 Table A6.5. Area and pollutant exports from the Wang Wauk River sub-catchments................. 548 Table A6.6. Percentage area of target and non-target land in the Wang Wauk River

sub-catchments, and the amount of total loads sourced from these lands............... 548 Table A6.7. Area and pollutant exports from the Coolongolook River sub-catchments............... 550 Table A6.8. Percentage area of target and non-target land in the Coolongolook River

sub-catchments, and the amount of total loads sourced from these lands............... 550 Table A6.9. Percentage area of target and non-target land in the Wallingat River

sub-catchments, and the amount of total loads sourced from these lands............... 552 Table A6.10. Area and pollutant exports from the Lower River Estuary sub-catchments.............. 557 Table A6.11. Percentage area of target and non-target land in the Lower Estuary

sub-catchments, and the amount of total loads sourced from these lands............... 557 Table A6.12. Area and pollutant exports from the southern and western sub-catchments

of Wallis Lake ...................................................................................................... 561 Table A6.13. Percentage area of target and non-target land in the southern and western

sub-catchments of Wallis Lake, and the amount of total loads sourced from these lands .................................................................................................. 561

Table A6.14. Area and pollutant exports from the Forster sub-catchments of Wallis Lake ........... 565 Table A6.15. Percentage area of target and non-target land in the Forster sub-catchments

of Wallis Lake, and the amount of total loads sourced from these lands ................. 565 Table A7.1. Key areas of future research and development for non-urban

catchment modelling ............................................................................................ 596 Table A7.2. Key areas of future research and development for estuarine response modelling ... 596 Table A7.3. Non-urban catchment modelling ........................................................................... 597 Table A8.1. Soil landscape types of the Wallis Lake catchment................................................ 605 Table A8.2. Percentage land use in the Wallis Lake catchment ................................................ 610 Table A8.3. Broad vegetation classes of the Wallis Lake catchment ......................................... 616 Table A8.4. Endangered ecological communities of the Wallis Lake catchment ........................ 616 Table A8.5. Regionally and locally significant vegetation communities of the

Wallis Lake catchment.......................................................................................... 617 Table A8.6. Examples of threatened terrestrial faunal species within the

Wallis Lake catchment.......................................................................................... 619 Table A8.7. Wallis Lake catchment management to date ......................................................... 622 Table A8.8. Riparian fencing ratio summary for the watercourses within the

Wallis Lake sub-catchments ................................................................................. 626 Table A8.9. Wallamba River catchment riparian fencing........................................................... 628 Table A8.10. Lower Wallamba River catchment riparian fencing ................................................ 628 Table A8.11. Wang Wauk River catchment riparian fencing ....................................................... 628 Table A8.12. Coolongolook River catchment riparian fencing..................................................... 628 Table A8.13. Minimbah Sandbed catchment riparian fencing ..................................................... 629 Table A8.14. Wallingat River catchment riparian fencing............................................................ 629 Table A8.15. Wallis Lake body catchment riparian fencing......................................................... 629

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Table A8.16. Summary of riparian fencing for all Wallis Lake catchment watercourses ............... 629 Table A8.17. Number of land parcels within each catchment where agricultural activities

are permissible.....................................................................................................630 Table A10.1. Methods for defining Ecological Condition Targets ................................................ 638 Table A10.2. Percentile chlorophyll-a concentrations for NSW lakes and estuaries..................... 640 Table A10.3. Long-term Ecological Condition Target values developed for the Great Lakes........ 641 Table A10.4. Short-term ‘event’ Ecological Condition Target values developed for the

Great Lakes ......................................................................................................... 641 Table A10.5. Long-term Ecological Condition Target values developed from the

80th percentile of available data for the Myall Lakes.............................................. 642 Table A11.1. Loads of nutrients from the catchment of each case study area ............................. 648 Table A14.1. Wallis Lake – Proposed remediation, protection and management support

actions for this Plan, and the time frame for their implementation ........................... 671 Table A14.2. Wallis Lake – Assumptions in costing the Water Quality Improvement Plan

and its actions...................................................................................................... 673 Table A14.3. Wallis Lake – Effectiveness at trapping pollutants for each level of dam condition .. 674 Table A14.4. Wallis Lake – Proportion of dams at each level of dam condition,

by management scenario ..................................................................................... 675 Table A14.5. Wallis Lake – Estimated effectiveness of dams for management scenarios ............ 675 Table A14.6. Wallis Lake – Estimation of costs for remediation of dams ..................................... 676 Table A14.7. Wallis Lake – Scenarios for Plan implementation for dam refurbishment ................ 676 Table A14.8. Wallis Lake – Description of the levels of nutrient management scenarios.............. 677 Table A14.9. Wallis Lake – Proportion of total improved pasture area at each level of

nutrient management, by management scenario ................................................... 677 Table A14.10. Wallis Lake – Scores and fertiliser multipliers, by nutrient management scenario.... 678 Table A14.11. Wallis Lake – Estimation of costs for fertiliser management ................................... 678 Table A14.12. Wallis Lake – Scenarios for Plan implementation for nutrient management ............ 679 Table A14.13. Wallis Lake – Description of the levels of groundcover condition scenarios ............ 679 Table A14.14. Wallis Lake – Proportion of groundcover area at each level of groundcover

management, by management scenario................................................................ 680 Table A14.15. Wallis Lake – Estimation of costs for groundcover management ............................ 681 Table A14.16. Wallis Lake – Scenarios for Plan implementation for groundcover management..... 682 Table A14.17. Wallis Lake – Costing of works for remediating unsealed roads ............................. 684 Table A14.18. Wallis Lake – Extent and costs of repairing stream bank erosion ........................... 687 Table A14.19. Wetland protection strategy – Wallis and Myall lakes............................................. 689 Table A14.20. Existing and future urban areas, Wallis and Smiths lakes catchments.................... 690 Table A14.21. Urban development of Greenfield sites for the Wallis Lake catchment.................... 692 Table A14.22. Wallis Lake – Reduction in TN, TP and TSS loads with implementation of

WSUD scenarios..................................................................................................693 Table A14.23. Wallis Lake – Sub-catchments used for urban area redevelopment scenarios ........ 696 Table A14.24. Wallis Lake – Scenarios for Plan implementation for

urban water use management .............................................................................. 697 Table A14.25. Wallis Lake – Costs of implementing ecological monitoring program ...................... 700 Table A15.1. Non-market Valuation Studies for Native Vegetation Conservation......................... 713 Table A15.2. Summary of Results of Travel Cost Studies .......................................................... 715 Table A15.3. Agricultural Output Values in the Great Lakes Statistical Local Area ...................... 719 Table A15.4. Potential Benefits and Costs of the Wallis Lake WQIP........................................... 723 Table A15.5. Direct Program Costs ........................................................................................... 723 Table A15.6. Wallis Lake Benefit Cost Analysis Results............................................................. 726 Table A15.7. Sensitivity Testing on River Health Values ............................................................ 727 Table A15.8. Wallis Lake WQIP BCA of Individual Actions......................................................... 728 Table A15.9. Potential Benefits and Costs of the Smiths Lake WQIP.......................................... 730 Table A15.10. Direct Program Costs ........................................................................................... 730 Table A15.11. Smiths Lake Benefit Cost Analysis Results ........................................................... 731 Table A15.12. Smiths Lake WQIP BCA of Individual Actions........................................................ 732 Table A15.13. Potential Benefits and Costs of the Myall Lakes WQIP .......................................... 735 Table A15.14. Potential Benefits and Costs of the Drinking Water Strategy for the

Crawford Catchment ............................................................................................ 736 Table A15.15. Direct Program Costs ........................................................................................... 736 Table A15.16. Myall Lakes Benefit Cost Analysis Results ............................................................ 739 Table A15.17. Myall Lakes Benefit Cost Analysis Results – Drinking Water Strategy for the

Crawford Catchment ............................................................................................ 740 Table A15.18. Sensitivity Testing on River Health Values ............................................................ 741 Table A15.19. Myall Lakes WQIP BCA of Individual Actions ........................................................ 741 Table A15.20. Drinking Water Strategy for the Crawford Catchment BCA of Individual Actions ..... 742 Table A16.1. Soil landscape types of the Smiths Lake catchment............................................... 751 Table A16.2. Land use summary for the Smiths Lake catchment................................................ 752

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Table A16.3. Threatened terrestrial faunal species detected in the Smiths Lake catchment by WBM (2000) .................................................................................................... 760

Table A16.4. Smiths Lake – Catchment management to date .................................................... 764 Table A17.1. Smiths Lake – Proposed remediation, protection and management support

actions for this Plan and the time frame for their implementation............................ 768 Table A17.2. Smiths Lake – Assumptions in costing the Water Quality Improvement Plan

and its actions...................................................................................................... 769 Table A17.3. Smiths Lake – Description for each level of groundcover ....................................... 770 Table A17.4. Smiths Lake – Proportion of grazing lands at each level of groundcover condition,

by management scenario ..................................................................................... 770 Table A17.5. Smiths Lake – Scenarios for Plan implementation for groundcover management.... 772 Table A17.6. Existing and future urban areas for Smiths Lake catchment ................................... 774 Table A17.7. Urban development of Greenfield sites for the Smiths Lake catchment................... 774 Table A17.8. Smiths Lake – Scenarios for Plan implementation for Greenfield developments ..... 775 Table A17.9. Smiths Lake – Costs of implementing water-sensitive urban design devices........... 775 Table A17.10. Smiths Lake – Scenarios for Plan implementation for water-sensitive

urban design management ................................................................................... 776 Table A17.11. Smiths Lake – Costs of implementing ecological monitoring program..................... 780 Table A18.1. Soil landscape types of the Myall Lakes catchment ............................................... 786 Table A18.2. Land use summary for the Myall Lakes catchment ................................................ 790 Table A18.3. Broad vegetation classes of the Myall Lakes catchment ........................................ 796 Table A18.4. Endangered ecological communities of the Myall Lakes catchment........................ 796 Table A18.5. Regionally and locally significant vegetation communities of the

Myall Lakes catchment ......................................................................................... 797 Table A18.6. Examples of threatened terrestrial faunal species within the Myall Lakes catchment ......................................................................................... 798 Table A18.7. Myall Lakes catchment management to date......................................................... 802 Table A18.8. Riparian fencing ratio summary for the watercourses within the Myall River,

Crawford River and Boolambayte Creek catchments............................................. 806 Table A19.1. Myall Lakes land use classes represented in the Great Lakes CCI DSS................. 810 Table A19.2. Area and pollutant exports from the Myall Lakes sub-catchment ............................ 814 Table A19.3. Percentage area of target and non-target land in the Myall Lake sub-catchment,

and the amount of total loads sourced from these lands ........................................ 815 Table A19.4. Area and pollutant exports from the Boolambayte Creek sub-catchment ................ 816 Table A19.5. Percentage area of target and non-target land in the Boolambayte Creek

sub-catchment, and the amount of total loads sourced from these lands ................ 817 Table A19.6. Area and pollutant exports from the Upper Myall River sub-catchment ................... 818 Table A19.7. Percentage area of target and non-target land in the Upper Myall River

sub-catchment, and the amount of total loads sourced from these lands ................ 819 Table A19.8. Area and pollutant exports from the Crawford River sub-catchment ....................... 820 Table A19.9. Percentage area of target and non-target land in the Crawford River

sub-catchment, and the amount of total loads sourced from these lands ................ 821 Table A19.10. Area and pollutant exports from the Bombah Broadwater sub-catchment ............... 822 Table A19.11. Percentage area of target and non-target land in the Bombah Broadwater

sub-catchment, and the amount of total loads sourced from these lands ................ 824 Table A19.12. Area and pollutant exports from the Lower Myall River sub-catchment ................... 824 Table A19.13. Percentage area of target and non-target land in the Lower Myall River

sub-catchment, and the amount of total loads sourced from these lands ................ 825 Table A20.1. Myall Lakes – Proposed remediation, protection and management support

actions for this Plan, and the time frame for their implementation ........................... 828 Table A20.2. Myall Lakes – Assumptions in costing the Water Quality Improvement Plan

and its actions...................................................................................................... 829 Table A20.3. Myall Lakes – Effectiveness at trapping pollutants for each level of dam condition.. 830 Table A20.4. Myall Lakes – Proportion of dams at each level of dam condition,

by management scenario ..................................................................................... 831 Table A20.5. Myall Lakes – Estimated effectiveness of dams for management scenarios ........... 832 Table A20.6. Myall Lakes – Estimation of costs for remediation of dams .................................... 832 Table A20.7. Myall Lakes – Scenarios for Plan implementation for dam refurbishment................ 833 Table A20.8. Myall Lakes – Description of the levels of nutrient management scenarios ............. 833 Table A20.9. Myall Lakes – Proportion of total improved pasture area at each level of nutrient

management, by management scenario................................................................ 834 Table A20.10. Myall Lakes – Scores and fertiliser multipliers, by nutrient management scenario... 834 Table A20.11. Myall Lakes – Assumptions in costing the nutrient management actions ................ 834 Table A20.12. Myall Lakes – Scenarios for Plan implementation for nutrient management............ 835 Table A20.13. Myall Lakes – Description of the levels of groundcover condition scenarios............ 836 Table A20.14. Myall Lakes – Proportion of groundcover area at each level of groundcover

management, by management scenario................................................................ 836

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Table A20.15. Myall Lakes – Estimation of costs for groundcover management............................ 838 Table A20.16. Myall Lakes – Scenarios for Plan implementation for groundcover management .... 838 Table A20.17. Myall Lakes – Extent and costs of repairing stream bank erosion........................... 840 Table A20.18. Wetland protection strategy. Wallis and Myall lakes............................................... 841 Table A20.19. Urban development of Greenfield sites for the Myall Lakes catchment ................... 842 Table A20.20. Myall Lakes – Costs of implementing ecological monitoring program...................... 845 Table A21.1. Remediation actions considered for the Crawford River catchment ........................ 849 Table A21.2. Chlorophyll-a levels resulting from expanding programs

according to the Crawford Drinking Water Strategy ............................................... 853 Table A21.3. Cost ($) per unit of load controlled by rural actions applied across the

Crawford River catchment .................................................................................... 854 Table A21.4. Summary of recommended protection and remediation management actions

in the Crawford River sub-catchment .................................................................... 854 Table A21.5 Summary of total costs of Crawford River drinking water options

recommended by the Plan at seven years and 30 years ........................................ 855 Table A21.6. Crawford Drinking Water Plan benefit-cost analysis results.................................... 856 Table A21.7. Crawford Drinking Water WQIP benefit-cost analysis of individual actions.............. 857 Table A21.8. Proportion of pasture land in each level in the Crawford River sub-catchment ........ 858 Table A21.9. Costs specific to groundcover actions in the Crawford Drinking Water Strategy...... 858 Table A21.10. Proportion of improved pasture in each level in the

Crawford River sub-catchment.............................................................................. 859 Table A21.11. Costs specific to nutrient management in the Crawford Drinking Water Strategy .... 859 Table A21.12. Proportion of dams in each level in the Crawford River sub-catchment................... 859 Table A21.13. Costs specific to dam actions in the Crawford Drinking Water Strategy .................. 859 Table A21.14. Costs for implementing the Crawford Drinking Water Strategy ............................... 860 Table A23.1. Competencies of the sustainability organisation .................................................... 868 Table A24.1. Farm Scale Action Plan: Strategies to encourage landholder uptake of

water quality improvement actions ........................................................................ 870 Table A24.2. Technical strategies for water quality improvement at the farm scale...................... 875 Table A30.1. Monitoring sites for long-term targets .................................................................... 966 Table A30.2. Monitoring program costs ..................................................................................... 970

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GLOSSARY OF TERMS

AnnAGNPS The Annualised Agricultural Non-Point Source

(AnnAGNPS) model simulates quantities of surface water,

sediment, nutrients and pesticides leaving the land areas

and their subsequent travel through the watershed. More

information on this model can be accessed from the

Decision Support System (DSS) Overview window.

Benthic

The benthic zone is the ecological region at the bottom of

a water body, such as a lake, and includes the surface and

some sub-surface layers. The organisms that live in this

zone are called benthos.

Catchment Action Plan A Catchment Action Plan is used to guide investment to

protect and improve the natural resources of a region over

a given period. The Hunter-Central Rivers Catchment

Action Plan is a 10-year plan (2006 to 2016) for better

coordinated and more sustainable management of the

regions natural resources. It identifies the key natural

resource features that require protection and improvement,

and outlines the best ways to do this.

Catchment load The amount of nutrient or sediment that the estuary model

predicts will not cause exceedance of Ecological Condition

Targets.

Chlorophyll-a Chlorophyll-a is one type of the green pigment found in

plants known as chlorophyll. Measurements of chlorophyll-

a concentrations in a waterbody are used to estimate algal

biomass and to assess biological productivity.

Conceptual framework Conceptual frameworks in the Great Lakes DSS show the

relationship between land use and management actions,

and community values. An initial framework, developed

during the review phase, was presented to stakeholders

for discussion, and to ensure that management actions

and community values associated with the lake and its

catchment were included. The participatory activities were

used to refine the conceptual framework and to clarify the

types of actions to be included in the DSS.

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DCP Development Control Plans (DCPs) supplement LEPs and

are detailed guidelines that define controls that apply to a

particular type of development or in a particular area.

DSS There is no universally accepted definition of Decision

Support System (DSS), although in its most general form a

DSS is a tool to support decision-making. They are often

computer-based tools that allow users to explore current

and alternative options for managing the system of

interest. DSS developed at iCAM tend to feature three

main components:

Data base – numerical and/or qualitative information that

helps users familiarise themselves with the study system

and to explore the impacts of different options.

Model base – the models used to manipulate data and

generate output from user-defined actions. Data stored in

the data base are input to, or created by, the model base.

Interface – the DSS interface allows user to navigate

through the tool, run the models and view outputs. The

interface is kept separate from the model base to facilitate

the use of the DSS by users who are not familiar with

programming and computer models.

More information on the Great Lakes DSS can be

accessed from the DSS Overview window.

Ecological Condition

Targets

Numerical levels or descriptive statements that must be

met to maintain environmental values. In the Great Lakes

CCI, project condition targets have been set for

chlorophyll-a and turbidity.

Environmental value The value or use of the water that we wish to protect.

Hydrodynamic model

In the CCI project, a computer-based hydrodynamic model

was developed for each lake system. The model shows

where water (and water-borne, catchment-derived matter)

goes, and how long it stays there. The model is driven by

the physics of the system and considers wind, tides and

catchment inflows.

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Indicator A characteristic used to provide a measure of the condition

of ecosystem or quality of water.

LEP Local Environmental Plans (LEPs) are the principal legal

document at the council level for controlling the use and

development of land. LEPs are prepared by councils and

approved by the Minister after public exhibition of the plan.

Light attenuation Light attenuation determines how fast the light intensity

decreases with distance from objects and is measured as

an exponential loss rate per metre. It quantifies the amount

of light that is available for photosynthesis.

Littoral rainforest A type of rainforest that occurs within the influence of the

sea or a large coastal water body (e.g. lake or estuary).

This vegetation type is protected in New South Wales

under SEPP 26.

Macroalgae Algae that are not microscopic. The body of the plant can

be seen easily with the eye.

Macrophyte An aquatic plant that grows in or on the water and can be

free-floating, submergent or emergent.

MUSIC MUSIC (Model for Urban Stormwater Improvement

Conceptualisation) is designed to simulate urban

stormwater systems operating across a range of temporal

(minutes to daily) and spatial (0.01 km2 to 100 km2) scales,

and was developed by the Cooperative Research Centre

for Catchment Hydrology – Urban Stormwater Quality

Program. The model has been designed for urban

stormwater engineers, planners, policy staff and managers

in consultancies and state, regional and local government

agencies. More information on the use of MUSIC in the

CCI project can be accessed from the DSS Overview

window.

Potential for

eutrophication (PE)

The potential for excessive plant growth to occur in a water

body. It provides a measure of the risk of negative

outcomes such as nuisance algal blooms, transition to

phytoplankton dominance, more turbid waters and muddy

foreshores. The concentration of material in the water

column that might, at some time, be used for primary

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production is a reasonable indicator of PE. In the estuary

models developed for the Great Lakes CCI project,

nitrogen concentration in the water column is considered

to be a measure of PE.

Riparian vegetation Riparian vegetation is the vegetation on land adjoining,

directly influencing or influenced by a stream.

Secchi depth The depth that a 20 cm weighted black-and-white disk can

be seen into a water column, and is a measure of water

clarity.

SEPP State Environment Planning Policies (SEPP) are policies

proposed by the Minister and approved by the Governor.

SEPPs address matters of state significance.

Total Nitrogen A measure of all forms of nitrogen (e.g. nitrate, nitrite,

ammonia-N and organic forms) exported from lands or

present in a water body.

Total Phosphorus A measure of all forms of phosphorus (e.g. dissolved,

particulate) exported from lands or present in a water

body.

Total Suspended

Sediment

Total amount of suspended material in a water column,

and is a measure of water clarity.

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ABBREVIATIONS

AHD Australian Height Datum ALUM Australian Land Use and Management AnnAGNPS Annualised Agricultural Non-Point Source Pollution

model ARI[DG9] Average return interval ASRIS Australian Soil Resource Information System AUSRIVAS Australian River Assessment System BASIX NSW Building Sustainability Index BMP Best management practice BOD Biological oxygen demand CCI Coastal Catchments Initiative CMA Catchment Management Authority CRCCH Cooperative Research Centre for Catchment Hydrology CRP Current recommended practice DAGS Mid Coast Dairy Advancement Group DCP Development Control Plan DECC Department of Environment and Climate Change DIN Dissolved inorganic nitrogen DIPNR Department of Infrastructure, Planning and Natural

Resources (no longer current) DNR[DG10] Department of Natural Resources DON Dissolved organic nitrogen DoP Department of Planning DPI Department of Primary Industries DSS Decision Support System DWE Department of Water and the Environment EPA Environmental Protection Authority EP&A Act Environmental Planning and Assessment Act 1979

(NSW) GIS Geographical information system GLC Great Lakes Council GLLEP Great Lakes Local Environmental Plan GSC Gloucester Shire Council GTCC Greater Taree City Council HCRCMA Hunter-Central Rivers Catchment Management

Authority ICOLL Intermittently closed and opened lake or lagoon ISO International Standards Organisation km Kilometres LEP Local Environmental Plan m Metres MCW MidCoast Water MoU Memorandum of Understanding MUSIC Model for Urban Stormwater Improvement

Conceptualisation N Nitrogen NHT Natural Heritage Trust NPWS National Parks and Wildlife Service (NSW) NRM Natural resource management NSW New South Wales NTU Nephelometric turbidity units OAQC Oyster Assurance Quality Control

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OSM On-site Sewage Management P Phosphorus POEO Act Protection of the Environment Operations Act 1997

(NSW) REP Regional Environmental Plan SALIS Soil and Landscape Information System SEPP State Environmental Planning Policy SOE State of the Environment SoJI Statements of Joint Intent SPADE Pro Soil Profile Attribute Data Environment Professional TN Total nitrogen TP Total phosphorus TSS Total suspended solids g/L Micrograms per litre WQIP Water Quality Improvement Plan WSUD Water Sensitive Urban Design