February 2015Application Reference EN020001

Hinkley Point C Connection Project

Regulation 8(1)(e) of the Infrastructure Planning (Examination Procedure) Rules 2010

8.3.8Do

cum

ent

Statements of Common Ground Internal Drainage Boards

STATEMENT OF COMMON GROUND BETWEEN NATIONAL GRID and AXE BRUE, PARRETT AND NORTH SOMERSET LEVELS INTERNAL DRAINAGE BOARDS

Version 5

Hinkley Point C Connection project

National Grid National Grid House Warwick Technology Park Gallows Hill Warwick CV34 6DA

February 2014

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Table of Contents

1 STATEMENT OF COMMON GROUND ................................................................................... 5 1.1 Introduction and purpose .......................................................................................................... 5 1.2 Request of Examining Authority ............................................................................................... 5 1.3 Internal Drainage Boards .......................................................................................................... 6 1.4 Viewed Rhynes ........................................................................................................................ 6 1.5 Role of and dialogue with the Internal Drainage Boards ........................................................... 6 1.6 Structure of this statement of common ground ......................................................................... 9

2 MATTERS CONCLUDED ...................................................................................................... 10 2.1 Key principles ......................................................................................................................... 10 2.2 Proximity of works or features to watercourses....................................................................... 10 2.3 Flood risk ................................................................................................................................ 11

3 MATTERS AGREED IN PRINCIPLE ..................................................................................... 12 3.1 Regulation of watercourse crossings ...................................................................................... 12 3.2 Surface water runoff ............................................................................................................... 15

4 MATTERS NOT CONCLUDED .............................................................................................. 17 4.1 Reimbursement of IDB costs .................................................................................................. 17 4.2 Proximity of works or features to watercourses....................................................................... 18 4.3 Retention of regulatory powers ............................................................................................... 18 4.4 Groundwater movements ....................................................................................................... 21

APPENDICES AND FIGURES

Appendix 1: Temporary Construction Access Standard Details Culvert Specification (ref: MMD-322069-C-DR-GEN-XX-2005 Rev P2)

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Document control

Document properties

Organisations National Grid / Axe Brue IDB / Parrett IDB / North Somerset Levels IDB

Author Joe Turner

Approved by Joe Turner

Title Statement of Common Ground between National Grid and Axe Brue, Parrett and North Somerset Levels Internal Drainage Boards

Document Reference N/A

Version History

Date Version Status Description/Changes

05/09/2014 1 Superseded Draft issued for review to Axe Brue IDB

30/01/2015 2 Superseded Draft issued to IDBs for comment

19/02/2015 3 Superseded Draft incorporating IDB comments

24/02/2015 4 Superseded Draft incorporating further IDB comments

25/02/2015 5 Live Draft incorporating further IDB comments

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1 STATEMENT OF COMMON GROUND

1.1 Introduction and purpose

1.1.1 The Hinkley Point C Connection application for Development Consent (“the Application”) was made by National Grid Electricity Transmission Ltd (“National Grid”) on 28th May 2014 and accepted for examination by the Planning Inspectorate on 17th June 2014 (reference number: EN020001).

1.1.2 This Statement of Common Ground (“SoCG”) has been prepared by National Grid Electricity Transmission Ltd (“National Grid”) and the Axe Brue and Parrett Internal Drainage Boards (working together as the Somerset Drainage Boards Consortium) and the North Somerset Levels Internal Drainage Board, in accordance with the guidance1 published by the Department of Communities and Local Government.

1.1.3 The purpose of the SoCG is to set out agreed factual information about the application for Development Consent made by National Grid. It is intended that the SoCG should provide matter on which National Grid and the other party or parties agree. As well as identifying matters which are not in dispute, the SoCG may also identify areas where agreement has not been reached, or reached in principle subject to further discussions. Where relevant, the SoCG will include references to show where these matters are dealt with in the application, written representations or other documentary evidence.

1.1.4 It is envisaged that the SoCG may evolve during the examination of the proposals by the Examining Authority (ExA). Subsequent drafts will be agreed and issued, with the version numbers clearly recorded in the ‘Document Control’ table at the beginning of the document.

1.2 Request of Examining Authority

1.2.1 The Preliminary Meeting to discuss the examination procedure was held on 19 January. The Examining Authority (ExA) reiterated its request, originally made in its procedural decision of 28 November 2014, for SoCGs to be prepared by National Grid and the North Somerset Levels Internal Drainage Board (NSLIDB) and Somerset Drainage Boards Consortium (SDBC). This SoCG therefore covers the two Internal Drainage Boards – Axe Brue and Parrett covered by the SDBC – as well as the NSLIDB.

1.2.2 The ExA has requested that the SoCG should include material on:

Principal Issue 5: Flood Risk, including application of existing by-laws or satisfactory substitute measures, continued operation of water courses, mitigation of surface water run-off and access for long-term maintenance; and

Principal Issue 6: Ground Conditions, Water Quality and Pollution Prevention including measures to avoid detriment to underground water movements from underground works.

1.2.3 These matters are included in the SoCG alongside other matters discussed with the three IDBs.

1 Planning Act 2008: Guidance for the examination of applications for development consent (April 2013) paras.

57-62 https://www.gov.uk/government/publications/planning-act-2008-examination-of-applications-for-development-consent

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1.3 Internal Drainage Boards

1.3.1 Internal Drainage Boards (IDBs) are statutory water level, flood risk management and land drainage authorities, responsible directly to the Department for Environment, Food and Rural Affairs (DEFRA) and, since the Flood and Water Management Act 2010, also working in partnership with the Lead Local Flood Authority and other Risk Management Authorities in their districts.

1.3.2 IDBs operate in the lowland areas of England and Wales, and are mainly concentrated in Somerset (including North Somerset), South Gloucestershire, East Anglia, Yorkshire and Lincolnshire, where flood risks are high.

1.3.3 The principal duty laid on IDBs under the Land Drainage Act 1991, is to exercise a general supervision over all matters relating to the drainage of land within their statutory Drainage Districts.

1.3.4 IDBs have powers under the Land Drainage Act 1991 to undertake flood defence works, land drainage improvements and water level control, on all watercourses other than ‘main river’ (which are under the control of the Environment Agency), within their Drainage Districts.

1.3.5 IDBs monitor the condition of, undertake maintenance work on and control water levels in strategic watercourses, generally known as ‘Viewed Rhynes’. IDBs have powers to ensure that watercourses, other than those which they currently keep ‘In View’, are maintained by the riparian owners and, where an impediment to the natural flow occurs, they can require the riparian owner to undertake whatever clearance work the IDB deems necessary. IDBs also regulate the activities of others using their powers under the Land Drainage Act 1991 and Byelaws made under that Act.

1.4 Viewed Rhynes

1.4.1 Viewed Rhynes form the basic and essential connecting network of strategic arterial watercourses, usually linking to the ‘main river’ system. These are watercourses identified by the IDBs, in recognition of their importance to flood defence and land drainage, and of their role in supplying water for summer grazing of livestock and other agricultural needs. The designation of a watercourse as a ‘Viewed Rhyne’ is flexible and an IDB may take any ordinary watercourse into, or out of, ‘View’ as they choose and according to the changing needs of the area served. IDBs may also create new watercourses, or carry out improvement works to any watercourse (other than ‘main river’) in their District, to aid the efficient operation of the strategic watercourse system.

1.5 Role of and dialogue with the Internal Drainage Boards

1.5.1 The IDBs are statutory public bodies constituted under the Land Drainage Act 1991 set up in order to undertake water level management and flood risk functions in their catchment areas.

1.5.2 The Axe Brue Internal Drainage Board (ABIDB) catchment covers the catchments of the Axe and Brue Rivers, and the coastal catchment in the vicinity of the settlements of Brean, Berrow, Burnham-on-Sea and Highbridge.

1.5.3 The Parrett Internal Drainage Board (PIBD) was formed in 2005 as a result of an amalgamation of 13 Drainage Boards – Aller Moor, Bridgwater & Pawlett,

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Cannington & Wembdon, Chedzoy, Curry Moor, Dunster, Kings Sedgemoor & Cary Valley, Langport, Northmoor, Othery Middlezoy & Westonzoyland, Stanmoor, Stockland and West Sedgemoor. It covers the catchments of the Rivers Parrett, Tone, Isle, Yeo and their tributaries, and parts of West Somerset.

1.5.4 The North Somerset Levels Internal Drainage Board (NSIDB) is also a single Board formed in 2011 as a result of the amalgamation of the North Somerset (2005) and West Mendip Drainage Boards. It covers three catchment areas in North Somerset, two in the Board’s North Area and one in its South Area. The North Area catchments are 1) the Gordano Valley catchment, a low-lying area between Tickenham Ridge and the coastal ridge known as Portishead Down; and 2) the catchment to the south of Tickenham Ridge extending westward to the coast between Clevedon and the river Congresbury Yeo; while the South Area catchment comprises a substantial part of the town of Weston-super-Mare, plus that part of the low-lying North Somerset Moors and Levels extending inland from Weston-super-Mare and Kewstoke, to Wick St Lawrence, Congresbury, Churchill, Sandford, Banwell, Locking, Hutton and Uphill.

1.5.5 The operations and affairs of the ABIDB and the PIDB are managed by the Somerset Drainage Boards Consortium which also provides engineering services to NSLIDB. Discussions on drainage matters have therefore been undertaken by National Grid with the Consortium.

1.5.6 However, the individual Boards are the legal corporate bodies with powers and duties under the Land Drainage Act 1991 and other relevant legislation.

1.5.7 The three IDBs and National Grid are hereafter collectively referred to in this SoCG as ‘the parties’. The three IDBs are hereafter collectively referred to as ‘the IDBs’.

1.5.8 This SoCG is based on a programme of engagement and discussions with the IDBs, as summarised in the tables below:

Somerset Drainage Boards Consortium

Date Details

30 June 2010 Letter from Somerset IDBs Consortium outlining its interests in the project.

11 January 2012 Letter from Somerset IDBs Consortium covering undergrounding and approach to gaining consents.

9 January 2013 Meeting to discuss consultation announcement in previous November and technical specifications for watercourse crossings.

21 February 2013 Email from Somerset IDBs Consortium on EIA scoping report, outlining the Board’s interests in the project and its regulatory powers.

25 February 2013 Email from Somerset IDBs Consortium on EIA scoping report, recommending amendments to the material on the Hydrology chapter.

22 May 2013 Meeting to discuss technical and engineering issues.

17 September 2013 Letter from Somerset IDBs Consortium covering: location of towers, minimum separation distances from watercourses, haul road crossing types and sizes, outstanding survey information, headwall details, haul road details, underground cable installation and works compound details.

20 September 2013 Meeting to discuss technical and engineering issues.

11 October 2013 Letter from Somerset IDBs Consortium on subject of a consent agreement under the Land Drainage Act 1991 and reimbursement of the Boards’ costs.

28 October 2013 Response by Somerset IDBs Consortium to statutory consultation, setting out key principles on: 1) 9m clearance widths for watercourses; 2) regulations of watercourse crossings; and 3) surface water runoff rate.

3 March 2014 Response to Southwick revised route consultation, reiterating points made in 28 October 2013 letter.

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Date Details

19 September 2014 Meeting to discuss SOCG and technical issues (joint meeting with North Somerset Levels IDB).

16 February 2015 IDB comments on Version 2 of the SoCG (joint with North Somerset Levels IDB).

24 February 2015 Further IDB comments on Version 3 of the SoCG (joint with North Somerset Levels IDB).

North Somerset Levels IDB

Date Details

6 July 2010

Consultation response stating that the IDB has no preference on corridors but will require close liaison regarding crossings of watercourses, including future meetings when decision on route is finally agreed.

10 January 2013

Meeting to update IDB on project and ascertain specific IDB requirements. The main points were:

IDB requested that no pylons are located within 9 metres of their

watercourses, and any construction activities in this area could be

acceptable but would require consultation.

Cables under watercourses would need to be a minimum of 1 m

below bed of ditch and protected by a protection layer. This cover

should extend to 1 metre either side of the watercourse.

Culverts should follow the IDB’s ‘Policy for Culverts’ but generally the

max. diameter would be c.1.2 metres.

IDB confirmed a ‘common sense’ consent approach would be taken

and that consents can be grouped into one application.

23 May 2013 Meeting with North Somerset Levels IDB:

Culvert diameter should typically be 1.2 metres on viewed rhynes, and 600mm on field ditches with a minimum 450mm.

Twin culverts are not favourable as they collect weeds and debris which can cause blockages leading to flooding.

Box culverts are preferred.

IDB would require access to maintain watercourses in construction areas to prevent flooding; advance notice would be given.

The IDB has no objections to diversion of watercourse adjacent to Sandford substation as it would be likely to improve the drainage, provided that continuity of flow is maintained. A weir could be used for discharge at peak, but any discharge would need to be consented. The new ditch would need to have the same cross sectional area as the existing ditch.

No objections in principle were identified by the IDB.

7 August 2013 Meeting with North Somerset Levels IDB:

IDB concerned that standard culverts would be used – National Grid confirmed that each crossing would be surveyed and the culvert implemented accordingly.

IDB stated that there would be some clear spans required in the Yatton area in particular and highlighted: Biddle Street Rhyne, Wemberham Lane Rhyne, New Rhyne Lampley and Yatton Little River. DC added that historically Yatton had flood issues in the area due to incorrect culverting and now concrete clear spans had been put in place to mitigate this. GJ to feed this back to NG design team.

IDB reiterated concern over double culverts, unless National Grid staff are on site to manage the risk.

IDB indicated a conservationist on site would be useful to deal with ecology issues.

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Date Details

18th September

2013 Meeting with North Somerset Levels IDB:

IDB reiterated principle of combining multiple watercourse consents into a single application, which would be considered preferable.

All culverts would be treated as permanent for the purpose of the consenting process.

IDB requested that culvert installation allows for changes in silt levels and flow throughout the year.

IDB stated that in considering culvert positions and provisions for overpumping during installation, overpumping may not actually be required for some locations due to redundancy within the drainage network. MB added that this would have to be considered for each individual location.

IDB reiterated concern over access to construction site for watercourse maintenance. In particular, a 9 metre clearance height would be required for maintenance purposes.

IDB raised the issue of reimbursement of costs for involvement in the project.

19 September 2014 Meeting to discuss SOCG and technical issues (joint meeting with Somerset Drainage Boards Consortium).

16 February 2015 IDB comments on Version 2 of the SoCG (joint with Somerset Drainage Boards Consortium).

24 February 2015 Further IDB comments on Version 3 of the SoCG (joint with Somerset Drainage Boards Consortium).

1.6 Structure of this statement of common ground

1.6.1 Section 2 of this SoCG describes the ‘matters concluded’, where agreement has been reached with the parties.

1.6.2 Section 3 identifies matters agreed in principle subject to further details.

1.6.3 Section 4 identifies the ‘matters not concluded’, where there are still differences between National Grid and the parties.

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2 MATTERS CONCLUDED

2.1 Key principles

2.1.1 During pre-application discussions between and consultation with the IDBs and National Grid, three key principles emerged, in relation to:

1) proximity of works or features from watercourses;

2) regulation of watercourse crossings, including construction of vehicle crossing points across watercourses, overhead and underground cable crossings or other features pass over or under a watercourse; and

3) surface water run-off, including the impacts of the development on surface water run off rates and overall volumes of run off and flow/drainage routes, which must have, at worst, a neutral impact on flood risk, drainage and water level management of the area.

2.1.2 The IDBs are also concerned that water tables and movement of groundwater are not adversely affected.

2.1.3 The matters of common ground between the parties on these principles are discussed in turn below. The term ‘watercourse’ is used in this SoCG to refer specifically to ‘ordinary watercourses’ under the regulatory control of the IDBs. Ordinary watercourses are deemed to be all rivers and streams and all ditches, drains, cuts, culverts, dikes, sluices, sewers (other than public sewers vested with utilities) and passages, through which water flows that are not classified as Main River by the Environment Agency. Therefore, the watercourses referred to exclude all ‘main rivers’ (these being under the regulatory control of the Environment Agency).

2.2 Proximity of works or features to watercourses

2.2.1 The IDBs have requested that:

“Any new infrastructure, including pylon or tower bases, haul roads, fencing, compound areas or any other construction, is sited at least 9m away from the banks of any watercourse. We regulate activities such as these under our Land Drainage Byelaws. Land Drainage Consent will be required from the Board for any proposals within the 9m Byelaw width.”

2.2.2 National Grid has committed that:

No permanent structures (pylon bases, substations, cable sealing end compounds etc.) with the exception of any permanent watercourse crossings, are proposed within 9 metres of the banks of any watercourse. Were any such structure to be required within the Order limits allowed for in the Development Consent Order, consent would be sought from the relevant IDB; and

Working areas, where possible, will not be located within 9 metres of the banks of any watercourse. However, there are likely to be locations where the haul road runs parallel to and within 9 metres of a watercourse. Where works are within 9m, approaches will follow guidance in PPG5: Works in, near or liable to affect watercourses and where works are required to be located within 9 metres of any watercourse, consent will be sought from the relevant IDB.

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2.2.3 As the Hinkley Point C Connection project is a linear scheme, it is not possible to avoid running close to and crossing numerous watercourses with construction haul roads as requested by the IDB. These crossings are discussed further in ‘Regulation of watercourse crossings’ below.

2.2.4 With the exception of the matters outlined in the ‘matters to be concluded’ section below in relation to haul roads, the parties agree that the above approach represents an appropriate means of ensuring adequate clearance from watercourses, and where necessary the regulation of works close to watercourses, during the construction of the Hinkley Point C Connection project.

2.3 Flood risk

2.3.1 Flood Risk Assessments (FRAs) were submitted with the application with respect to:

Bridgwater Tee Cable Sealing End Compounds (Volume 5.23.1);

South of the Mendip Hills CSE Compound (Volume 5.23.2);

Sandford Substation (Volume 5.23.3);

Seabank Substation (Volume 5.23.4); and

The route of the Hinkley Point C Connection (Volume 5.23.5).

2.3.2 Following discussions with the Environment Agency, a revised version of the FRA for the connection route has subsequently been submitted and accepted into the examination on 27 January 2015 (Volume 5.23.5.1A).

2.3.3 The mitigation measures recommended by the FRAs in relation to flood risk are set out in paras. 3.4.11- 3.4.15 of the revised CEMP (Volume 5.26.1A). Further regulatory controls on flood risk, and in particular watercourse reinstatement, would be secured through the various requirements in Schedule 3 to the DCO that are discussed above, and through the watercourse consenting regimes of the IDBs (in the case of ordinary watercourses) and the Environment Agency (in the case of main rivers).

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3 MATTERS AGREED IN PRINCIPLE

3.1 Regulation of watercourse crossings

3.1.1 The IDBs have requested that:

“Any watercourse access crossing point, cabling that passes beneath any watercourse, or any other construction in, under or over any watercourse is constructed in such a way that will not adversely impact the on the ability of the watercourse to function properly, be maintained efficiently or be improved in future. We regulate these activities under section 23 of the Land Drainage Act. Land Drainage Consent for these types of proposal will be required from the Board.”

3.1.2 Given the linear nature of the proposals, there are over 300 crossings of watercourses (rivers, ditches, rhynes etc.) across the Hinkley Point C Connection project. All of these watercourses (with the exception of main rivers) fall within the regulatory control of the IDBs under the Land Drainage Act 1991 and associated Byelaws, and consent will be required for each crossing regardless of whether the watercourse is a ‘viewed rhyne’.

3.1.3 In most cases, there are no existing crossings in place. In such circumstances, National Grid will ensure that the specification of the culvert supplied to facilitate the crossing will ensure that the hydraulic performance, capacity etc. of the existing watercourse is matched. Given uncertainty over the structural condition of existing watercourse crossings, it is likely that these will need to be replaced. These would also be designed to match the hydraulic performance, capacity etc. of the existing watercourse.

3.1.4 Land Drainage Consent under section 23 of the Land Drainage Act would be sought for all new and altered watercourse crossings. This is confirmed at para. 2.1(k) of Volume 7.3 (Details of Other Consents and Licences).

3.1.5 Notwithstanding the requirement for consent for these crossings, discussions have taken place with the IDBs with regard to survey of the viewed rhynes and other watercourses, and the specification of the culvert or bridge to be required. These are based on the following general design principles:

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Item Description

Culvert diameter Each culvert will be designed and consented on a case-by-case basis to match the hydraulic performance, capacity etc. of the existing watercourse, but will follow the following typical diameters:

1.2m or clear span box culvert for viewed rhynes

450mm-600mm for other watercourses depending on physical / hydraulic factors, with larger diameters where considered necessary

Culvert level All culverts would be installed using hard levels, as determined by topographical surveys, as the base, in order to allow for seasonal level and flow changes.

Double culverts Double culverts will be avoided to avoid collection of debris.

Cable crossing depth All cables would have some form of protective layer above.

All cables (inclusive of protection layer) will be placed at least 1m below the bed of watercourses, extending to 1m either side of the watercourse. However, details of construction are still to be agreed and may be more onerous where necessary.

Overhead line crossings

Overhead line crossings must be of sufficient height to allow safe and effective passage underneath for plant and vehicles undertaking watercourse maintenance.

Over-pumping Over-pumping during installation of culverts will be considered on a case-by-case, but may not actually be required for some locations due to redundancy within the drainage network.

3.1.6 The drawing at Appendix 1 (Temporary Construction Access Standard Details Culvert Specification) provides further indicative details with regard to culvert specification and the graph overleaf (Figure 1) provides indicative culvert sizes based on ditch sizes.

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Figure 1: graph showing indicative culvert size based on ditch size

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3.1.7 Requirement 19 (Inspection of temporary watercourses) of Schedule 3 to the Draft Development Consent Order (Volume 2.1A) requires that:

“19.—(1) No stage of the authorised development may commence until a written scheme for the inspection and clearance of debris from any temporary watercourse required in connection with that stage has, after consultation with the Environment Agency and the relevant drainage authority, been submitted to and approved by the relevant planning authority.

(2) The approved scheme shall be implemented for each temporary watercourse during the construction of that stage of the authorised development until such time as the temporary watercourse has been removed.”

3.1.8 The definition of temporary watercourses under Requirement 19 includes all temporary culverts placed into an existing watercourse (NB. this drafting has been provided by the Environment Agency). Requirement 19 will therefore allow the IDBs to exert further control over the management of the temporary crossings to ensure they are managed properly. In particular, it will allow operational and maintenance arrangements to be agreed before any new features that affect any of the watercourses are implemented. It should be noted that the drafting for this requirement has been provided by the Environment Agency, and is intended to apply to culverts required for watercourse crossings.

3.1.9 Furthermore, Requirement 20 (Removal of temporary bridges and culverts) ensures that all temporary bridges and culverts will be removed within 12 months of the completion of the construction of that stage of the development for which they are required (or such further time as may be agreed with the IDB).

3.1.10 The parties agree that the above approach represents an appropriate means of controlling the management of new features that affect watercourse, subject to the agreement of the details of proposals through the mechanisms suggested above and the Land Drainage Consent regime,

3.2 Surface water runoff

3.2.1 The IDBs have requested that:

“Any new construction will not increase the surface water runoff rate or volume of water entering the drainage network or detrimentally affect surface water distribution within the local or wider catchments. Land Drainage Consent will be required for any new connections or modifications to existing connections.”

3.2.2 Detailed drainage proposals will be designed and agreed prior to the construction phase and detailed proposals are not available at this stage. However, several different mechanisms are in place to control drainage to ensure that neither the drainage network nor surface water distribution is affected. These are set out below:

Section 3.5 of the Draft Construction Environmental Management Plan (CEMP) (Volume 5.26.1A) sets out a series of measures for the protection of the water environment. The implementation of the CEMP is secured by

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Requirement 5 of Schedule 3 to the Draft Development Consent Order (Volume 2.1A).

Requirement 17 (Surface water drainage) requires that drainage management plans are submitted for approval by the local planning authority, in consultation with the relevant IDB and Environment Agency, prior to the construction of all phases of development, and that these plans are implemented.

As is noted above, Requirement 19 provides for control of the inspection of temporary watercourses (culverts) and Requirement 20 ensures that all temporary bridges and culverts will be removed within 12 months of the completion of the construction of that stage of the development for which they are required (or such further time as may be agreed with the IDB).

Requirement 21 (Accumulation and deposits) allows for the control of accumulations and deposits, such as bunds, soil storage mounds etc. to ensure that these do not interfere with drainage.

As is noted above, Land Drainage Consent under section 23 of the Land Drainage Act would be sought for all alterations to watercourses, including any new connections or modifications.

3.2.3 The parties agree that in principle the above approach represents an appropriate means of controlling surface water runoff and drainage, subject to the agreement of the details of proposals through the mechanisms suggested above and the Land Drainage Consent regime,

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4 MATTERS NOT CONCLUDED

4.1 Reimbursement of IDB costs

4.1.1 The IDBs have stated that, to assist in developing the details and to process any Land Drainage Consent applications, the Boards will require reimbursement of expenses for their legal, administrative, technical, engineering and supervision / inspection tasks for all matters associated with this development. The Consortium’s preferred means of securing such payment is via a consent agreement under the Land Drainage Act 1991. It is noted that a statutory application fee is payable for applications for Land Drainage Consent.

4.1.2 However, the IDBs have stated that the costs of registering, assessing, processing and granting the applications for Land Drainage and Byelaws consent for this project is likely to exceed the administrative fee referred to and will therefore place an additional financial burden upon the public purse through an increase in the Drainage Rates and Special Levy paid by the public to the Board for the additional work it will have to undertake. The IDBs consider that this financial burden should be borne by the applicant, not the general public, and therefore proposes a schedule of rates to be agreed between the Boards and National Grid which shall be used to record and charge time expended in excess of the statutory fee to National Grid, for dealing with applications and consultations regarding this project.

4.1.3 National Grid recognises the burden that would be placed on the IDBs and agrees in principle to the reimbursement of IDB costs for some types of engagement once the DCO is made. This agreement in principle is subject to the following principles and limitations:

National Grid will pay the statutory fees required to determine Land Drainage Consents. National Grid agrees in principle to pay a greater sum for an enhanced service level (e.g. pre-application discussion; faster decision-making etc.) to cover costs reasonably incurred by the IDBs in discussing, assessing and determining Land Drainage Consents to provide the enhanced service, at a rate to be agreed. The IDBs do not agree with this position.

Any payments cannot be used to subsidise the normal functions and duties of the IDBs. The IDBs agree with this position.

Costs for IDB engagement in the examination of the proposals by the Planning Inspectorate will not be reimbursed. The IDBs consider this also to be an additional burden which should be funded by the applicant.

The costs of IDB supervision and monitoring of works will not be reimbursed. National Grid’s position is that as a responsible developer, it will have robust monitoring and compliance systems. The Construction Environmental Management Plan secured by the DCO (Requirement 5) includes measures for the monitoring and management of the works to minimise local environmental impacts by National Grid. If National Grid fails to do this, relevant statutory enforcement procedures apply. Furthermore, a communication and complaints management system is a requirement of the DCO (Requirement 31). For this reason, National Grid’s view is that it is not considered appropriate for National Grid to provide funding the IDBs’ statutory monitoring and enforcement function. The IDBs do not agree with this position.

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Any payments would be made directly to the relevant drainage board (or the Somerset IDBs Consortium if appropriate) rather than via the local planning authorities or any other third party. The IDBs agree with this position.

4.1.4 Given the large number of watercourses affected, National Grid would be open to a discussion about grouping consents in order to realise efficiencies and for consents to be assesses in a co-ordinated and holistic way.

4.1.5 The parties will continue discussions with regard to the mechanism for the reimbursement of IDB costs.

4.2 Proximity of works or features to watercourses

4.2.1 Whilst the IDBs support the commitment to work in accordance with PPG5, they are concerned that haul roads and their use may affect the stability of watercourse banks, causing blockages to the channel and increased water levels. The IDBs are also concerned that the proximity of haul roads, associated fencing and other temporary features will obstruct linear access routes for watercourse maintenance. Where access is obstructed and maintenance by the Boards and others is not possible, they would require National Grid to undertake necessary channel maintenance to an agreed schedule.

4.2.2 The parties will continue to work to reach agreement on these matters.

4.3 Retention of regulatory powers

4.3.1 As previously noted, the IDBs have made clear in discussions and consultation responses that its powers to seek and determine Land Drainage Consent and to control activities within the 9 metre byelaw width should be retained.

4.3.2 Article 49 of the Draft Development Consent Order (DCO) (Volume 2.1A) submitted with National Grid’s application for development consent would have the effect of ensuring the some local legislation would not apply to the proposed development, including several of the Axe Brue Internal Drainage Board Land Byelaws 2012, the North Somerset Levels Internal Drainage Board Land Drainage Byelaws 2011 and the Parrett Internal Drainage Board Drainage Byelaws 2006. The byelaws that would be ‘disapplied’, as listed in Part of Schedule 16 of the DCO, are as follows:

Byelaw 3 (control of introduction of water and increases in flow or volume of water)

Byelaw 7 (detrimental substances not to be put in watercourses)

Byelaw 14 (vehicles not to be driven on banks)

Byelaw 15 (banks not to be used for storage)

Byelaw 17 (fences, excavations, pipes, etc.)

Byelaw 26 (obstruction of the Board and Officers)

4.3.3 Subsequent to National Grid’s application for development consent, National Grid agreed that the following byelaws, which were to be disapplied in the submission draft of the DCO (Volume 2.1), should remain in force:

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Byelaw 6 relating to diversion and stopping up of watercourses

Byelaw 9 relating to the cutting of vegetation and stopping up of watercourses and

Byelaw 10 relating to obstructions within 9 metres of the watercourse.

4.3.4 These byelaws are therefore not listed in Schedule 16 of the revised DCO (Volume 2.1A).

4.3.5 The following table explains National Grid’s reasoning for the disapplication of the remaining Byelaws:

Byelaw Title and summary Reasoning

3 Control of introduction of water and increase in flow or volume of water

Prohibits introduction of water, directly or indirectly, into watercourse without consent of the board.

Dealt with by the measures set out under ‘Surface water runoff’ above –

Section 3.5 of CEMP; Requirements 17 (surface water drainage), 19 (Inspection of temporary watercourses) and 21 (Accumulation and deposits)

7 Detrimental substances not to be put into watercourses

Prohibits placing of objects in watercourse and also in proximity to a watercourse to render the same liable to drift, drain or be blown into a watercourse

As for Byelaw 3 above

14 Vehicles not to be driven on banks

No vehicle to be driven over or along any bank in such a manner as to cause damage to such a bank.

The byelaw does not define manner of driving nor damage to banks which may not be driven on banks. The crossing of watercourses by vehicles will be necessary in order to construct the proposed development.

Appropriate controls will be put in place regarding the use of vehicles in such circumstances.

15 Banks not to be used for storage –

which may damage the banks, interfere with operation of the IDB or the right of the IDB to deposit spoil

As for Byelaw 3 above

20

Byelaw Title and summary Reasoning

17 Fences, Excavations, Pipes etc.

Prevents, without consent of the IDB, the placing of any electrical main or cable or wire in or over any watercourse or in, over or through any bank of any watercourse.

This would require Land Drainage Consent for all crossings of the 400kV and 132kV overhead lines subject to the development consent application, which is not considered proportionate. Other crossings (e.g. cables and haul road crossings) will already be subject to Land Drainage Consent.

26 Obstruction of the Board or Officers

Prohibits interference with officers of the IDB in exercising their powers under these byelaws.

Provides for such interference where the exercise of the power under the byelaws is inconsistent with the implementation of the DCO. This is necessary to ensure that the NSIP can be delivered promptly, efficiently and safely, and in particular that the access of officers is consistent with National Grid’s Construction Design and Management procedures and obligations.

4.3.6 Byelaw 24 (Damage to the property of the Board) states that “no person shall interfere with or damage any bank, bridge, building, structure, appliance or other property of or under the control of the Board”. The watercourse crossings required for National Grid’s proposed development would clearly interfere with the watercourses in question. As it is now proposed that Byelaws 6 and 10 will remain in force, it is considered that Byelaw 24 may be disapplied, since the controls in place under the above arrangements would allow adequate powers for the IDBs to regulate these works.

Current positions

4.3.7 National Grid believes that the above approach is proportionate and enables the IDBs to effectively carry out their statutory duties to undertake water level management and flood risk functions whilst allowing the timely delivery of this nationally significant infrastructure project.

4.3.8 However, whilst recognising that the initial proposal to disapply the Boards Byelaws has now been modified to retain Byelaws 6,9 and 10, the IDBs can see no reason for the disapplication of any of the Boards’ Byelaws and therefore resist the disapplications proposed. The IDBs fully intend to work co-operatively with National Grid and the IDBs’ professional partners and therefore see the risk to National Grid of retaining these Byelaws as very small. However, they feel it is

21

essential to retain their full existing regulatory framework alongside the requirements within the DCO.

4.3.9 The parties will continue to work to reach mutually acceptable arrangements on these matters.

4.4 Groundwater movements

4.4.1 The IDBs are concerned that water tables and movement of groundwater are not adversely affected. These issues are assessed in detail in the Ground Environment and Hydrology and Water Resources chapters of the Environmental Statement (Volumes 5.9.1 and 5.10.1).

4.4.2 National Grid will continue to work with the IDBs to understand and address their concerns in this regard.

22

25/02/2015

23

Appendix 1: Temporary Construction Access Standard Details Culvert Specification (ref: MMD-322069-C-DR-GEN-XX-2005 Rev P2)

Typical Circular Culvert Ditch

1:20

DN

BC

Outline of ditch

Bottom of Haul Road

DN

XD

CB

CH

H

Q

Bottom of Haul Road

Outline of ditch

Typical Box Culvert Ditch

1:20

H

ED+

X

ID

ED

ID+

D

Q

NG INVESTMENT No. APPLICATION No.

NG DRAWING No. DRAWING No. SCALE

ISSUE

TITLE:

ISSUE DATE COMMENTS CHK'D APP'DDRAWN

Notes

MMD DRAWING No.

COPYRIGHT NOT TO BE REPRODUCED WITHOUT THE WRITTEN PERMISSION OF THE NATIONAL GRID ELECTRICITY TRANSMISSION Plc

MMD-322069-C-DR-GEN-XX-2005

P2

As Shown

NATIONAL GRID

HINKLEY C CONNECTION PROJECT

TEMPORARY CONSTRUCTION ACCESS

STANDARD DETAILS

CULVERT CLASSIFICATION

20897

ACAD

A1

Circular Culvert Type Details Table

Nominal Pipe

Diameter (DN)

(mm)

Outside

Diameter of

Pipe (BC) (mm)

Cover (H) (mm)

Depth between Bottom of Ditch

and Haul Road (mm) (X) (mm)

Depth of Ditch (D) (mm)

(see note 6)

Width of Ditch Base (Q)

(mm)

Concrete Bedding

(CH x CB) (mm)

Minimum Maximum Minimum Maximum Minimum Maximum

300 410 600 4450 955 4910 460 4860 410 - 3500 610 x 177.5

450 (IDB)

575 600 4625 1112 5250 460 5200 410-770 775 x 256.25

600 770 600 4800 1285 5620 820 5570 770 - 1500 970 x 342.5

1. All dimensions in millimetres unless otherwise

stated.

2. Do not scale any items of information from this

drawing.

3. SHW - Specification for Highways

4. All concrete in accordance with BS 8500

5. Circular concrete culverts to comply with and tested

to BS 5911:2010. Box concrete culverts comply with

XD3 exposure class and BS5400

6. Culvert crossing has been designed in accordance

with BS 1295-1:1997 Structural design of buried

pipelines under various conditions of loading - Part 1:

General & BS 9295:2010 Guide to the structural

design of pipeline. Maximum loading have been

assume to be the maximum loading permitted on the

Highways network as described in the

aforementioned standards.

7. For Bellmouth construction details refer to drawing

MMD-322069-C-DR-GEN-XX-2000.

8. Refer to drawing nos.

MMD-322069-C-DR-GEN-XX-2002, 2003 and 2004

for proposed culvert details.

9. Drawing to be read in conjunction with drawing

MMD-322069-C-DR-GEN-XX-2002, 2003 and 2004.

10. Design has allowed for minimal settlement.

Maintenance regime to be in place to monitor

settlement and increase culvert cover when

necessary whilst also ensuring culverts are not

blocked.

11. All works shall be carried out in accordance with

National Grid Technical Specification (NGTS).

12. Culvert design and drainage consents (where

applicable) to be approved/agreed with the relevant

IDB/ditch owner prior to commencing works.

Box Culvert Type Details Table

Internal Dimensions

(ID x ID+) (mm)

External Dimensions

(ED x ED+) (mm)

Cover (H) (mm)

Depth between Bottom of Ditch

and Haul Road (mm) (see note 6)

Depth of Ditch (D) (mm)

(see note 6)

Width of ditch Base (Q)

(mm)

Minimum Maximum Minimum Maximum Minimum Maximum

1000 x 600 1390 x 990 200 20000 1395 20050 640 18000 1400 - 2200

1500 x 600 2005 x 990 200 20000 1952 20050 640 18000 2000 - 3500

1m2m0

1:20

MMD-322069-C-DR-GEN-XX-2005

P1

28/04/14Detail Design

JAH EVI JW

P2

13/06/14Detail Design

JAH EVI MS