REPORT

Stolford Flood Defence Scheme Environmental Statement Non-Technical Summary

Client: Environment Agency

Reference: I&BPB4311R001F00

Revision: 00/Final

Date: 19 November 2017

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19 November 2017 STOLFORD FDS NTS I&BPB4311R001F00 i

HASKONINGDHV UK LTD.

Stratus House

Emperor Way

Exeter

EX1 3QS

Industry & Buildings

VAT registration number: 792428892

+44 1392 447999

+44 1392 446148

info.exeter@uk.rhdhv.com

royalhaskoningdhv.com

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F

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W

Document title: Stolford Flood Defence Scheme Environmental Statement Non-Technical Summary

Document short title: Stolford FDS NTS Reference: I&BPB4311R001F00

Revision: 00/Final Date: 19 November 2017

Project name: Stolford FDS Project number: PB4311

Author(s): Laura Covington

Drafted by: Laura Covington

Checked by: Peter Thornton

Date / initials: 19/11/2017 PMT

Approved by: Richard Samphier

Date / initials: 19/11/2017 RS

Classification

Project related

Disclaimer No part of these specifications/printed matter may be reproduced and/or published by print, photocopy, microfilm or by any other means, without the prior written permission of HaskoningDHV UK Ltd.; nor may they be used, without such permission, for any purposes other than that for which they were produced. HaskoningDHV UK Ltd. accepts no responsibility or liability for these specifications/printed matter to any party other than the persons by whom it was commissioned and as concluded under that Appointment. The integrated QHSE management system of HaskoningDHV UK Ltd. has been certified in accordance with ISO 9001:2015, ISO 14001:2015 and OHSAS 18001:2007.

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19 November 2017 STOLFORD FDS NTS I&BPB4311R001F00 ii

1 Introduction and Background

The Environmental Statement (ES) presents the findings of the Environmental Impact Assessment (EIA) for the proposed Stolford Flood Defence Scheme (FDS).

Stolford is a community of about 20 properties on the West Somerset coast. The village is partially protected by a low shingle ridge which fronts an area of saltmarsh known as Catsford Common. The Common is backed by an earth embankment (the secondary embankment) to the rear and is approximately 250m distant from the shingle ridge at its widest extent. The Common is open to the tide at its eastern end, and is therefore tidally inundated.

Currently, the Environment Agency maintains the shingle ridge by recycling shingle from its eastern end to its western end, on an “as and when required” basis. If maintenance of the shingle ridge was not undertaken, it is likely that a breach would occur within ten years. This would place the village of Stolford at risk from flooding from the sea as a result of overtopping of the secondary embankment as well as the longer term risk of erosion and failure of the embankment. This would result in 20 properties within Stolford and approximately 70 hectares of agricultural land and farm accesses becoming flooded. In addition, the only road in and out of Stolford would become impassable. The recycling is becoming increasingly ineffective, unsustainable and uneconomic; therefore a sustainable flood protection solution for Stolford to protect people and property is being sought by the Environment Agency.

The proposed scheme would raise and protect the rear (secondary) embankment along a 180 metre length. At the same time the recycling of the shingle ridge would cease. The works would effectively extend the existing rockwork that currently terminates at the Stolford Car Park. A design objective has been to minimise the footprint of construction activities on Catsford Common, as well as minimising the scheme footprint in the long term where appropriate to the required protection and standards required.

Further details of the proposed Stolford FDS are given in Section 5 in the Environmental Statement (ES), and the scope of works is shown on Figure 1.

The construction phase of Stolford FDS would consist of preparatory and main construction works. The works would commence following planning approval and discharge of any relevant pre-commencement requirements. It is anticipated that the works would commence in April 2017, provided planning permission is received within our programme timescales, and would take approximately 16 weeks including mobilisation, site preparatory works and de-mobilisation. Alternatively works could be undertaken in spring 2019 or beyond if there are any delays in receipt of planning permission.

Mud

Stert Flats

Catsford Common

Farm

Whitewick

Pond

St Peter's

Cottages

Idson

Stolford

Idson Farm

Stolford

North Ham

Mud

Croft Farm

Pond

Rock

Stert Flats

Sharpham

Submarine Forest

Chalcott Farm

Woolstone Farm

Stert Flats

Mud

Mud

Pond

Farm

Marsh

Mud and Shingle

Rock

Shingle

Mud

Stert Flats

Rock

Shingle

Mud

Mud

Shingle

Mud and Shingle

Mud

Mud

Rock

Mud

Mud

Catsford Common

Mud

Stert Flats

Mud

Flats

Mud

Ponds

Stert

D'Arches

Seaview

The Old Dairy

Cottage

Pond

Willow Barn

6.2m

Mudhorse Cottage

Pond

Cottage

Stolford Farm

The Bungalow

Stable

Lime Kiln

Pond

Sluice

OUTFALL WORKS

EMBANKMENT TOE

EXISTING ROCK

ARMOUR

PROTECTION

PATCH AND REPAIR WORKS

TO EXISTING OUTFALL,

MANHOLE AND ASSOCIATED

PIPEWORK

EXISTING OUTFALL STRUCTURE TO

REMAIN

TYPICAL SECTION 225.00

HORIZ. 1:200 VERT. 1:200

-90.00

5.56

-85.00

5.64

-80.00

5.71

-75.00

6.06

-70.00

6.05

-65.00

6.24

-60.00

8.43

-55.00

8.57

-50.00

6.75

-45.00

5.85

-40.00

5.47

-35.00

5.39

-30.00

5.71

-25.00

6.04

-20.00

6.15

-5.00

6.31

0.00

6.31

+8.95

CREST

EMBANKMENT

28419

+7.25

2017 WL

100 YR RP3

1

7.5

1

300mm HILL BLOCK

REVETMENT

CREST

3000

+7.64

2067 WL

100 YR RP

2Nr. LAYERS 10 - 60kg

ROCK ARMOUR

MARINE PLY

STAKES/BOARDS

TOE DETAIL

5100

GEOTEXTILE

BULK FILL

(TYPE 6F-TBC)

200mm GRANULAR

FILTER LAYER

1000

MIN.

LAND DRAIN

FOR FULL INFORMATION

SEE PB4311 STOLFORD GIR

ST-BH01

CONCRETE

CREST DETAIL

BENCHING TO SUIT

LAYER THICKNESS FOR

COMPACTION

METHODOLOGY OF FILL

MATERIAL

LEGEND

SITE PLAN

SCALE 1:500

LOCATION PLAN

SCALE 1:20000

SITE LOCATION

1. ALL DIMENSIONS ARE IN MILLIMETRES UNLESS NOTED

OTHERWISE.

2. ALL LEVELS ARE IN METRES RELATIVE TO CHART DATUM (CD)

UNLESS NOTED OTHERWISE.

3. ALL COORDINATES ARE IN METRES RELATIVE TO WORLD

GEODETIC SYSTEM 1984 (WGS84) UNIVERSAL TRANSVERSE

MERCATOR (UTM) ZONE XXX.

4. ALL MATERIALS AND WORKMANSHIP WILL BE AS DEFINED IN

THE SPECIFICATION UNLESS NOTED OTHERWISE.

SCALE IN METRES

1:500

0 10 20 30m10 5152025m

SCALE IN METRES

1:20000

0 400 800 1200m400m

TVO-MS-ZZ-DR-C-1306

TVO-MS-ZZ-DR-C-1306 S2 P1

PB4311

AMJG

AS SHOWNFEB' 2017

GG

NOTES

DRAWN

DATE

CHECKED

SCALE

APPROVED

c

DRAWING No. REVISION

HaskoningDHV UK Ltd.

TITLE

CLIENT

BY CHK APPDESCRIPTION

REVISIONS

REV DATE

PROJECT

DRG No.

SOMERSET PACKAGE

STOLFORD FLOOD

DEFENCE SCHEME

Emperor Way, Stratus House,

Exeter, EX1 3QS

Tel +44(0)1392 447999

Email info.exeter@uk.rhdhv.com

Website www.royalhaskoning.com

REPRODUCED FROM ORDNANCE SURVEY MAPS WITH PERMISSION FROM THE

CONTROLLER OF HM STATIONERY OFFICE. CROWN COPYRIGHT RESERVED.

LICENCE No. 100026380.COPYRIGHT © ENVIRONMENT AGENCY 2016.

CLIENT REF.

IMSW002037

REF.

SUITABILITY

PLANNING BOUNDARY

CONSTRUCTION COMPOUND

FOOTPRINT OF OUTFALL WORKS

PROPOSED EMBANKMENT WORKS

PROPOSED ARMOUR PROTECTION WORKS

PROPOSED FOOTPATH WORKS

PROPOSED EMBANKMENT TOE WORKS

P120-11-17

S2 - FIT FOR INFORMATION GG LC AM

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19 November 2017 STOLFORD FDS NTS I&B

2 The Existing Environment

General habitats within and surrounding the proposed scheme include Catsford Common (saltmarsh) and the shingle ridge towards the sea with semi-improved grassland inland separated by ditches. Commoners have grazing rights over Catsford Common, although the grazing quality is poor at the western extent where the proposed scheme is located.

The secondary embankment is covered in dense scrub, which provides habitat for bats and breeding birds. Field boundaries are key habitat features across the area and predominantly comprise hedgerows with fence lines, often accompanied by a ditch. The field boundaries are dominated by species such as nettle and coarse grasses, although occasional flowering plants occur to add some floristic interest. Stolford is located within the Quantock Vale National Character Area.

The proposed scheme lies within the boundary of the Severn Estuary Special Area of Conservation (SAC), Special Protection Area (SPA) and Ramsar sites (that form the Severn Estuary Natura 2000 site) and the Bridgwater Bay Site of Special Scientific Interest (SSSI). These sites are designated for their estuarine habitats, fish species such as sea and river lamprey, and populations of over-wintering and passage wading birds and waterfowl.

The Bridgwater Bay National Nature Reserve (NNR) is located on the seaward side of the shingle ridge, next to the proposed scheme. The NNR is a component part of the Severn Estuary Natura 2000 site, and it also has an important invertebrate assemblage.

In addition, the proposed scheme study area r supporting habitats for other designated sites and species in the wider area, notably the:

Exmoor and Quantock Oakwoods SAC and associated Quantocks SSSI, which are designated for their populations of Barbastelle bats whose territories could extend to the proposed scheme area.

The Somerset Levels and Moors SPA and Ramsar site which are designated for their wetland habitats and key assemblages of over-wintering and passage wading birds and waterfowl, and along with their component SSSIs are ecologically linked to the Severn Estuary as their waterfowl and wading bird populations travel between both sites.

Key protected species present include overwintering birds, bats, and eels.

Bridgwater Bay at this location falls within the Parrett Transitional Water Body. It is currently classified as having moderate status due to the existing flood defences. The aim for the water body is to have Good Ecological Status by 2021.

Consultation with the Environment Agency Archaeologist and Somerset County Archaeologist has identified that there is limited potential for uncovering archaeological remains which are, at present, unknown. There are no designated historic environment assets within the area of proposed works; though there are three listed buildings in Stolford.

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Commercial fishing activities operating out of Stolford for crustaceans are carried out by a fisherman mainly collecting brown shrimps and a range of fish; he is locally (and nationally) known as the mud-horse fisherman.

A network of Public Rights of Way (PRoW) is present in the area around Stolford, and these include the England Coast Path.

Stolford is surrounded by agricultural land (of Provisional Agricultural Land Classification Grades 3) that is used for both grazing (sheep and cattle primarily).

3 Key Environmental Impacts and Proposed Mitigation Measures

The predicted residual impacts (largest to smallest) and associated key mitigation measures for the assessed environmental receptors have been identified for the construction and operation

phases of the proposed scheme.

3.1 Socio-economics, Community, and Amenity and Recreation

Construction: Short-term and temporary negligible to minor adverse residual impacts as a result of having to walk a further distance due to the temporary PRoW re-routing.

Construction: Short-term and temporary moderate adverse increase to traffic movements.

Construction: Short-term and temporary moderate adverse disruption to access to Wick Moor Common, Catsford Common and Hinkley Point Emergency Access Route and muster Point.

Construction: Short-term and temporary negligible disruption to grazing availability on a small area of Catsford Common.

Operation: Moderate beneficial due to reduced flood risk to residents and the PRoWs

Operation: Negligible loss of grazing area on Catsford Common.

3.1.1 Mitigation

Temporary closure and re-routing of sections of PRoWs will ensure that access along the shore and Common are not prevented. Fencing and signage will be used for safety, and all routes will be monitored.

Access for Commoners, Farmers and Hinkley Point Police to be managed locally with a banksman.

A Traffic Management Plan (TMP) has been drawn up to ensure that good practice is employed during construction, including the detailed movements and timings of construction traffic.

Access to the foreshore is to be maintained for the mud-horse fisherman during

construction, and a permanent access built into the proposed scheme.

3.2 Noise

Construction: Short-term and temporary negligible noise impacts.

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3.2.1 Mitigation

Follow Best Practice Noise management measures.

3.3 Historic Environment

Construction: Short-term and temporary negligible impact to setting and historic landscape character.

Operation: Minor to moderate beneficial improvement through reduction of flooding of Grade II listed buildings.

Operation: No impact to setting and historic landscape character.

3.3.1 Mitigation

Follow the measures set out in the TMP and where possible limit the number of HGV movements to minimise potential for vibration to impact on listed buildings.

3.4 Landscape and Visual

Construction: Short-term and temporary minor to moderate adverse impact on landscape character.

Construction: Short-term and temporary minor to moderate adverse impact on visibility

Operation: Minor to moderate adverse impact on landscape character.

Operation: Minor to moderate adverse impact on visibility.

3.4.1 Mitigation

There are no identified mitigation measures that can reduce the impacts on landscape and visual.

3.5 Water

Construction: Short-term and temporary negligible risk of deterioration in water body status due to spillage or release of sediments

Operation: Negligible change to water body status.

3.5.1 Mitigation

Ensure that the working methodology adheres to the CIRIA`s Environment Good Practice on Site, 3rd Edition; and Construction Industry Publication (CIP) Construction Environmental Manual.

3.6 Ecology

Construction: Short-term and temporary minor adverse impact to saltmarsh habitats that are disturbed reducing to no impact over time once habitats re-colonise.

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Construction: Short-term and temporary negligible impact to breeding birds and reptiles while habitats re-establish, reducing to no impact over time.

Construction: No impact to wintering or passage birds.

Construction: No impact to otter, reptiles, badger or water vole.

Operation: No impact to bats, breeding birds, badger and eel.

Operation: Loss of 0.343ha of saltmarsh. Compensatory habitat required.

3.6.1 Mitigation

Main construction activities to be started after eel migratory period (after 15th May).

Ensure flow is maintained through Little Arch Sluice for eel passage during construction.

Works to be completed before the end of September.

Reinstatement of habitats and planting of scrub to offset loss.

Ensure otter and badger can get out of open trenches.

Carry out scrub removal before the breeding bird period (1st March-31st August). If any additional vegetation removal is required carry out a check survey for nesting birds.

Implement the Precautionary Method of Working for Reptiles.

Give a toolbox talk on ecology to all site personnel.

Ensure that the working methodology adheres to the CIRIA`s Environment Good Practice on Site, 3rd Edition; and Construction Industry Publication (CIP) Construction Environmental Manual.

Any shingle that falls within the direct footprint of the revetment will be moved and placed within the undisturbed section of shingle ridge.

0.343ha of compensatory saltmarsh habitat to be provided as part of Steart Habitat Creation Scheme. This will offset the loss of 0.343ha of saltmarsh to the scheme.

A check survey will be required in late Spring 2017 to confirm the exact locations of rare plants.

4 Conclusions

Overall, Stolford FDS will result in improved flood defences in the long-term, with a greater level of protection to properties in Stolford. It will also enable the natural geomorphological processes associated with the European site (Severn Estuary) to return.

Once mitigation measures have been implemented the proposed scheme will result in construction and operation impacts that are negligible to minor in scale and significance, whilst providing an array of environmental enhancements that will benefit the local community and surrounding environment of Stolford.