23.0 tidal lagoon swansea bay

23.0 Tidal Lagoon Swansea Bay

Water Framework Directive

Screening

July 2013

Tidal Lagoon Swansea Bay plc

Tidal Lagoon Swansea Bay

Water Framework Directive Screening

Contents

1.0 Water Framework Directive - Screening.....................................1

1.1 Introduction ................................................................................1

1.2 Overview of Project ....................................................................1

1.3 Consenting Process .....................................................................2

1.4 Overview of the Project ..............................................................2

2 The Water Framework Directive ................................................6

2.1 Introduction ................................................................................6

2.2 Methodology ..............................................................................6

2.3 Study Area (Stage 1) ...................................................................7

2.4 WFD Baseline (Stage 2) ............................................................ 11

2.5 Relationship of the Proposed Development to relevant

WFD Waterbodies (Stage 3) .................................................... 15

2.6 WFD Preliminary Assessment (Stage 4) ................................... 18

2.7 WFD Detailed Assessment (Stage 5) ........................................ 23

Appendix 1 Water Framework Directive Article 4.7



Water Framework Directive Screening Page 1

1.0 Water Framework Directive - Screening

1.1 Introduction

1.1.0.1 This assessment has been prepared in support of the PEIR published in relation to a

prospective DCO application for the Tidal Lagoon Project1 in Swansea Bay with a nominal

rated capacity of 240MW. A summary of the Project is provided below and a detailed

description of the proposed development can be found in Chapter 4: Project Description

of the PEIR.

1.1.0.2 During pre-application consultation, Natural Resources Wales (NRW) indicated that a

Water Framework Directive (WFD) Screening Assessment was required to form part of

the Environmental Impact Assessment. A WFD Screening Assessment determines

whether a proposed development is compliant with the objectives of the WFD, or if

further assessment is required. This assessment, therefore, screens the Project and its

component elements against the WFD.

1.2 Overview of Project

1.2.0.1 TLSB is proposing to construct and operate a tidal energy lagoon, located in Swansea Bay,

South Wales (Figure 1.1). The tidal lagoon will generate renewable energy in the form of

electricity using the large tidal range (the difference between high and low water) which

is a distinguishing feature of the Bay. The lagoon will have a rated capacity of 240

Megawatts (MW), generating 400GWh net annual output. This is enough electricity for

approximately 121,000 homes: more than Swansea’s annual domestic electricity use

(109k households); c.70% of Swansea Bay’s annual domestic electricity use (Swansea,

Neath & Port Talbot, 173k households); or c.9% of Wales’ annual domestic electricity use

(based on 1,369k households).

Figure 1.1: Location of proposed tidal lagoon

1 Definitions used in this [Report] are, so far as possible, the same as those used in the PEIR.




1.2.0.2 In addition to generating electricity, the Project also aims to provide visitor facilities and

other amenities including art, education, mariculture and sporting/recreational facilities.

The seawall is expected to be open to the public during daylight hours for walking, running,

cycling etc, though access will be controlled in extreme weather.

1.3 Consenting Process

1.3.0.1 As the Project is an offshore electricity generating station of more than 100MW, it is

considered to be a Nationally Significant Infrastructure Project (NSIP) under the Planning

Act 2008. Construction of such a project requires that a DCO is first granted by the

Secretary of State for Energy and Climate Change via an application to the Planning

Inspectorate (PINS) under the 2008 Act.

1.3.0.2 The Project is located in Welsh coastal waters and therefore it also requires a marine

license to be granted via an application to the Marine Licensing Team of Natural Resources

Wales (NRW) on behalf of the Welsh Government. Additional consents may also be

required from the local planning authorities – City & County of Swansea Council (CCSC) or

Neath Port Talbot County Borough Council (NPTCBC) – for elements of the Project which sit

outside the NSIP and DCO. Table 1.1 below summarises the components and consenting

requirements of the Project.

Table 1.1: Summary schedule of consents

Group of works Description Consenting process

Offshore Works The turbines, with their housing and other facilities such as

generators and switchgear; seawall enclosing the new lagoon;

provision for roll-on/roll-off ferry berthing facility; integral

visitor centre, leisure facilities and public realm; emergency

and operational facilities; dredging works; works to Swansea

Port Channel; works to Neath Harbour Channel; works to

existing long sea outfall; navigation facilities; ecological

enhancement and mitigation; and navigational/lighting

works.

These works will be authorised by

the DCO and, to the extent they are

marine works, will require a marine

licence. The consent would include

powers to construct temporary

works such as cofferdams or

lighting.

Grid Connection

Works

The cable works embedded in the seawall; cable from the

landfall of the Offshore Works to the existing Baglan

substation in Neath Port Talbot; and a cable crossing of the

River Neath by direct drilling (going underneath the river).

These works will be authorised by

the DCO. The cable crossing of the

River Neath will require a marine

licence.

Onshore Works Provision of a temporary working area, access routes and

road accesses for construction of the Project;

decontamination works; operation and maintenance (O&M)

facilities, with slipways; vehicle parking and manoeuvring

areas; onshore visitor and recreational facilities; and right-of-

way and seashore works/mitigation within the lagoon

including treatment of storm water and interfaces with

Crymlyn Burrows SSSI.

These parts of the Project will be

authorised by the DCO.

Access Works Provision of access to the Project including necessary

demolitions; swing bridge(s); cycle routes; highway

improvements; and other works.

These parts of the Project will be

authorised by the DCO, but may

also be the subject of applications

to local planning authorities under

the TCPA 1990.

1.4 Overview of the Project

1.4.1.1 In order to control the flow of seawater to generate electricity, the Tidal Lagoon will be

built by forming a 9.5km-long, U-shaped seawall (Figure 1.1) running from Swansea Port

out to sea before curving back to re-join land adjacent to Swansea University’s new Science

and Innovation Campus (SAIC). Access to the Project, and supporting onshore facilities at

these two (Swansea Port and Campus) landfalls, will be from Fabian Way.




1.4.1.2 The seawall will have a sediment core held in place by a casing of sediment-filled geotextile

tubes, known as Geotubes®. The outside of the structure will be covered in rock armour of

various sizes, depending on its level of exposure (Figure 1.2). The sand used to form the

walls will be taken from within the lagoon footprint. Rock armour will then be brought in

by sea to provide protection. The top of the seawall will have an access road which will be

used for operation and maintenance of the lagoon as well as for visitors.

Figure 1.2: Example cross-section through lagoon seawall

1.4.0.3 In the south-western part of the seawall there will be a turbine/sluice gate housing

structure (Figure 1.1). The housing structure will contain between 16 and 22 hydro (water)

turbines, which will be permanently underwater (Figure 1.3). These turbines (which will be

7m-8m in diameter) will generate electricity on both the flood (in-coming) and ebb (out-

going) tides. There will also be around 10 sluice gates – these are large gates which will be

underwater and able to let seawater in and out of the lagoon without going through the

turbines, as required.

Figure 1.3: Cross-section of turbine housing structure

1.4.0.4 To generate electricity, as the sea starts to rise (flood tide) from low tide level, water is

prevented from entering the lagoon for an average of 2 hours 5 minutes, and this creates a

difference in water levels known as ‘head’. Once sufficient head has been reached, the

water is allowed to flow into the lagoon through the turbines, turning the runner (like a

propeller) and generating electricity. This process is repeated on the ebb tide, where the

water is prevented from leaving the lagoon until there is sufficient head to start the

process again (Figure 1.4).




Figure 1.4: Illustration of water flow between the sea and the lagoon

1.4.0.5 Towards the end of the ebb or flood tide the sluice gates will be opened. This is to empty

or fill the lagoon as quickly as possible before low or high tide level. By doing this, it

ensures that the lagoon water level is as close to the outside sea level as possible, before

the tide starts to rise or fall again. This is to maximise electricity generation and to keep the

intertidal area as close as possible to that occurring naturally outside the lagoon. An option

to pump the seawater at the end of the tide is also being looked at to further equalise

seawater levels.

1.4.1.6 This generation sequence will happen on both the flood and ebb tides, four times a day in

total. Figure 1.5 below illustrates this generating cycle.

Figure 1.5: Indicative 48-hour operating cycle for the lagoon

1.4.0.7 The electricity generated from the lagoon will be transported to the nearest National Grid

substation at Baglan by underground cables. The cables will be laid in the seawall and then

alongside existing roads/paths to the River Neath and onto the substation. To cross the

River Neath, the cable will either be put through existing disused pipes or it will be drilled

underneath the river.

1.4.1.8 At the end of the lifetime of the project (120 years) there are a number of potential

options for decommissioning and these are outlined below.

a. At the end of the working life of the facility, the turbines and sluice gates could be

removed, and the tide allowed to flow through the resultant gaps in the structure.

b. An alternative to this approach would be to remove a section of the breakwater bund

seawall from landfall of the eastern arm to where it meets the River Neath Cannel. The

other breakwater bunds would remain and the Lagoon would continue to be used for

Leisure.



c. As identified above if

requirements of the community and the Local Planning Authorities, requires removal of

sections of the breakwater bund, then this would be undertaken either by the use of

barge mounted excavators with con

large sections of the breakwater were to be removed then an option would be to

remove the sediment with a Cutter Suction Dredger, after removal of the rock armour

and underlayer.

d. It is equally likely that

generation by tidal Lagoons will have further developed, and the Swansea Tidal Lagoon

will be progressively updated so that the facility can be kept in use as an energy source

as well as its ongoing leisure use.

1.4.0.9 The components of the Project considered relevant to the WFD assessment comprise:

i. Construction dredging

ii. The lagoon walls and other offshore structure

iii. The turbine housing and

iv. Inlet channels and scour protection;

v. The water area within the proposed lagoon / offshore public realm;

vi. Emergency facilities and slipways (onshore and offshore);

vii. Operation and maintenance facilities, visitors centre including parking;

viii. Connection to the electricity grid; and

ix. Terrestrial ancillary in

cycle routes and parking).

1.4.0.10 The location of the proposed d

Figure 1.6 Location of the proposed Swansea Bay Tidal Lagoon


As identified above if the ongoing use of the Lagoon, as determined by the



barge mounted excavators with conventional land based excavators and dumpers. If



It is equally likely that at the nominal end of the working life of this facility, power



ngoing leisure use.

of the Project considered relevant to the WFD assessment comprise:

Construction dredging;

The lagoon walls and other offshore structures;

The turbine housing and turbines;

Inlet channels and scour protection;

ter area within the proposed lagoon / offshore public realm;

Emergency facilities and slipways (onshore and offshore);

Operation and maintenance facilities, visitors centre including parking;

Connection to the electricity grid; and

Terrestrial ancillary infrastructure (public realm facilities, highways infrastructure,

cycle routes and parking).

proposed development is shown in Figure 1.6.

Location of the proposed Swansea Bay Tidal Lagoon

Page 5

the ongoing use of the Lagoon, as determined by the



ventional land based excavators and dumpers. If



at the nominal end of the working life of this facility, power



of the Project considered relevant to the WFD assessment comprise:

ter area within the proposed lagoon / offshore public realm;

Operation and maintenance facilities, visitors centre including parking;

frastructure (public realm facilities, highways infrastructure,

Location of the proposed Swansea Bay Tidal Lagoon




2 The Water Framework Directive

2.1 Introduction

2.1.0.1 The Water Framework Directive (2000/60/EC) was given effect in the UK by the Water

Environment (Water Framework Directive) (England and Wales) Regulations 2003.

2.1.0.2 The WFD was put in place to:

a) Enhance the status, and prevent further deterioration of aquatic ecosystems and

associated wetlands which depend on the aquatic ecosystems;

b) Promote the sustainable use of water;

c) Reduce pollution of water, especially by ‘priority’ and ‘priority hazardous’

substances; and

d) Ensure progressive reduction of groundwater pollution2.

2.1.0.3 The WFD sets the objectives for all waterbodies in Europe classified under the WFD and the

requirement that they should reach at least good status (or potential) by 2015. This date

has been extended to 2027 in respect of a large number of waterbodies. Around 20% of

waterbodies in England in Wales are currently meeting the objective.

2.1.0.4 The WFD required member states to establish river basin districts and, for each, a

management plan. In Wales, as in England, WFD-related actions are managed through the

River Basin Management Plan (RBMP) process. For the Project, the relevant RBMP is the

Western Wales RBMP. The first Western Wales RBMP was published by Environment

Agency Wales in 2009 and is currently being updated by Natural Resources Wales.

Waterbody Action Plans (WAPs) are also available and these summarise the key features

and objectives of the waterbody along with updated information on the current status

WFD between revisions of the RBMPs.

2.1.0.5 The WFD has important implications for planning works that may affect relevant

waterbodies. It has the effect of controlling such development to circumstances where it

does not cause deterioration in waterbody status (ideally, such development should

improve the status of the affected waterbodies).

2.1.0.6 The WFD provides that, in the event that a proposed development would result in an

adverse effect on a waterbody, which could cause a deterioration in its WFD status or

could prevent actions which are required to raise the WFD status of the waterbody, then

the proposed development must be assessed and justified, in the context of the actions

proposed to mitigate the adverse impact on the status of the waterbody3.

2.2 Methodology

2.2.0.1 In order to assess whether the Project is compliant with the objectives set out in the WFD,

the following steps have been undertaken, or will be undertaken as part of preparation of

the Application for a DCO:

2 http://ec.europa.eu/environment/water/water-framework/

3 Water Framework Directive (2000/60/EC) Article 4.7




i. Stage 1 – Defining the study area, based on the distance of waterbodies from the

Project and the hydrological connectivity of waterbodies to the Project (discounting

those waterbodies not considered to be relevant);

ii. Stage 2 – Collating baseline data on the screened-in waterbodies, their current WFD

status, their specific objectives and any mitigation measures or failures undertaken to

date;

iii. Stage 3 – Defining the relationship of the Project's components with the included

waterbodies (screening out components not considered to be relevant);

iv. Stage 4 – A preliminary assessment of the remaining components of the Project

against the WFD elements (biological, chemical and hydromorphological element that

make up the overall WFD status) of the included waterbodies. This is to identify

whether any components could have an impact on the WFD elements and whether a

detailed assessment is required;

v. Stage 5 (if required) – Undertake a detailed assessment based on the findings of the

preliminary assessment in respect of any components of the Project identified as likely

to have an impact upon the WFD elements. This assessment will also consider any

conflicts between the Project and relevant RBMP mitigation measures, and any

cumulative effects of the development;

vi. Stage 6 (if Stage 5 required) – Proposed programme of compliance of development,

required in accordance with Article 4.7 of the WFD (Article 4.7 of the WFD is provided

in Appendix 1).

2.3 Study Area (Stage 1)

2.3.0.1 The Project will be situated within the Western Wales River Basin District and within the

Ogmore to Tawe Catchment.

2.3.0.2 Coastal waterbodies, transitional (estuarine) waterbodies, river waterbodies and

groundwater waterbodies that are adjacent, upstream and downstream of the Project

are shown below in relation to the proposed development in Figures 2.1, 2.2, 2.3 and 2.4

respectively, and their waterbody IDs provided.

2.3.1 Coastal

2.3.1.1 Coastal waterbodies that have been identified, adjacent or near to the proposed

development, are:

a) Swansea Bay (Coastal waterbody, GB641008260000)

b) Bristol Channel Outer North (Coastal waterbody, GB611008590001)




Figure 2.1 WFD Waterbodies – Coastal

2.3.2 Transitional (Estuarine)

2.3.2.1 Transitional (or estuarine) waterbodies that have been identified, adjacent or near to the

proposed development, are:

a) Tawe Estuary (Estuarine waterbody, GB541005900900)

b) Neath Estuary (Estuarine waterbody, GB541005800700)

Figure 2.2 WFD Waterbodies – Transitional (Estuarine)




2.3.3 River

2.3.3.1 River waterbodies that have been identified, adjacent or near to the proposed

development, are:

i. River Neath - confluence with Nedd Fechan and Mellte to tidal limit (River waterbody,

GB110058032430)

ii. River Tawe - confluence with Twrch to tidal limit (River waterbody, GB110059032180)

iii. River Tawe – confluence with Nant Cwmgelli to tidal limit (River waterbody,

GB110059025690)

iv. Crymlyn Brook – Headwater to confluence with Tennant Canal (River waterbody,

GB110059025700)

v. Neath and Tennant (River waterbody, GB71010012).

Figure 2.3 WFD Waterbodies - Rivers

2.3.4 Groundwater

2.3.4.1 A groundwater waterbody that has been identified, adjacent or near to the proposed

development, is:

a) Swansea Carboniferous Coal Measures (Groundwater waterbody, GB41002G201000)




Figure 2.4 WFD Waterbodies - Groundwater

2.3.5 Conclusions

2.3.5.1 The five WFD rivers identified above (GB110058032430, GB110059032180,

GB110059025690, GB110059025700 and GB71010012) are upstream of the proposed

development, and beyond the tidal limit, and therefore are not hydrologically connected

to the proposed development. Consequently, it is not considered that they will be

affected by the proposed development and they are not considered further within this

assessment.

2.3.5.2 The majority of construction and operation relating to the Project will be located within

the marine environment, and there exists the potential for pollution prevention measures

to control construction impacts for the terrestrial infrastructure components (see

Chapter 17). As such, Swansea Carboniferous Coal Measures Groundwater Waterbody

(GB41002G201000) is not considered likely. Notwithstanding this a small potential to

affect the saline wedge has been identified (Chapter 18 of the PEIR) and this is being

investigated further during the EIA.

2.3.5.3 Therefore, those waterbodies that comprise the study area, and that are considered

further within this assessment, are:

a. Swansea Bay (Coastal, GB641008260000);

b. Bristol Channel Outer North (Coastal, GB611008590001);

c. Tawe Estuary (Transitional, GB541005900900);

d. Neath Estuary (Transitional, GB541005800700); and

e. Swansea Carboniferous Coal Measures (Groundwater, GB41002G201000).

2.3.5.4 These are the waterbodies that are at greatest risk of being affected by the proposed

development.




2.4 WFD Baseline (Stage 2)

2.4.0.1 This section provides the WFD baseline conditions for those waterbodies comprising the

study area.

2.4.0.2 WFD baseline data on the assessed waterbodies is presented in Table 2.1. Information

presented is taken from the Western Wales RBMP (Appendix B) and the updated

Waterbody Action Plans (WAPs), provided to TLSB by Natural Resources Wales on 2 May

2013. Note that red text indicates WFD failures.

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ed

oxy

ge

n –

Hig

h

(cu

rre

nt)

, H

igh

(p

red

icte

d)

Co

pp

er

– H

igh

(cu

rre

nt)

,

Dis

solv

ed

In

org

an

ic

Nit

rog

en

:

Cu

rre

nt

Sta

tus:

Go

od

(WA

P)

Dis

solv

ed

Oxy

ge

n

Cu

rre

nt

Sta

tus:

Hig

h

(WA

P)

Fro

m R

MP

No

t a

t ri

sk -

Nit

rate

.

Pro

ba

bly

no

t a

t ri

sk f

or

dif

fuse

pe

stic

ide

s;

ph

osp

ho

rou

s, c

hlo

rin

ate

d

sub

sta

nce

, h

aza

rdo

us

sub

sta

nce

.

T

ida

l La

go

on

Sw

an

sea

Ba

y p

lc

Tid

al La

go

on

Sw

an

sea

Ba

y

Wa

ter

Fra

me

wo

rk D

ire

ctiv

e S

cre

en

ing

P

ag

e 1

3

Wa

terb

od

y

ID

No

.

an

d n

am

e

Est

ua

rin

e

Co

ast

al

Wa

ter

Gro

un

dw

ate

r

GB

54

10

05

90

09

00

Ta

we

Est

ua

ry

GB

54

10

05

80

07

00

Ne

ath

Est

ua

ry

GB

64

10

08

26

00

00

Sw

an

sea

Ba

y

GB

61

10

08

59

00

01

Bri

sto

l C

ha

nn

el

Ou

ter

No

rth

GB

41

00

2G

20

10

00

Sw

an

sea

C

arb

on

ife

rou

s

Co

al

Me

asu

res

Cu

rre

nt

sta

tus:

Hig

h

Pre

dic

ted

sta

tus

by

20

15

:

Hig

h

Hig

h (

pre

dic

ted

) T

olu

en

e –

Hig

h (

curr

en

t),

Hig

h (

pre

dic

ted

)

Info

rma

tio

n o

n

sup

po

rtin

g

con

dit

ion

s (H

yd

ro-

mo

rph

olo

gic

al)

Tid

al

Re

gim

e -

Fre

shw

ate

r

Flo

w.

Cu

rre

nt

sta

tus

-

“Su

pp

ort

s G

oo

d”

Pre

dic

ted

sta

tus

by

20

15

–

“Su

pp

ort

s G

oo

d”

Tid

al

Re

gim

e -

Fre

shw

ate

r

Flo

w.

Cu

rre

nt

sta

tus

-

“Su

pp

ort

s G

oo

d”

Pre

dic

ted

sta

tus

by

20

15

–

“Su

pp

ort

s G

oo

d”

No

in

form

ati

on

pro

vid

ed

wit

hin

RB

MP

or

WA

P

Mo

rph

olo

gy

Cu

rre

nt

Sta

tus:

Su

pp

ort

s

Go

od

Pre

dic

ted

Sta

tus

by

20

15

: S

up

po

rts

Go

od

No

t a

t ri

sk -

Sa

lin

e

intr

usi

on

.

Hy

dro

log

ica

l

rela

tio

nsh

ip w

ith

pro

po

sed

de

ve

lop

me

nt

Pro

po

sed

de

ve

lop

me

nt

is

loca

ted

pa

rtly

wit

hin

th

e

wa

terb

od

y

Pro

po

sed

de

ve

lop

me

nt

is

loca

ted

pa

rtly

wit

hin

th

e

wa

terb

od

y

Cro

sse

s th

e m

ari

ne

com

po

ne

nts

of

the

pro

po

sed

de

ve

lop

me

nt

Th

e p

rop

ose

d

de

ve

lop

me

nt

is l

oca

ted

insh

ore

wit

hin

th

e

ad

jace

nt

wa

terb

od

y

Th

e p

rop

ose

d

de

ve

lop

me

nt

is l

oca

ted

wit

hin

th

e g

rou

nd

wa

ter

bo

dy

are

a.

Ad

dit

ion

al

info

rma

tio

n f

rom

the

Wa

terb

od

y

Act

ion

Pla

ns

(WA

Ps)

Wa

terb

od

y i

s co

nsi

de

red

at

risk

of

ph

ysi

cal

or

mo

rph

olo

gic

al

alt

era

tio

n a

s a

resu

lt o

f d

red

gin

g.

W

ate

rbo

dy

is

con

sid

ere

d

pro

ba

bly

at

risk

of

po

int

sou

rce

po

llu

tio

n a

s a

re

sult

fro

m d

an

ge

rou

s su

bst

an

ces

an

d s

an

ita

ry d

ete

rmin

an

ds,

an

d a

lso

fro

m d

iffu

se s

ou

rce

po

llu

tio

n a

s a

re

sult

of

nu

trie

nt

nit

rog

en

.

Wa

terb

od

y i

s co

nsi

de

red

at

risk

of

ph

ysi

cal

or

mo

rph

olo

gic

al

alt

era

tio

n

as

a r

esu

lt o

f d

red

gin

g.

W

ate

rbo

dy

is

als

o

con

sid

ere

d p

rob

ab

ly a

t

risk

fro

m p

oin

t a

nd

dif

fuse

sou

rce

po

llu

tio

n a

s a

resu

lt o

f o

rga

nic

en

rich

me

nt

an

d s

an

ita

ry

de

term

ina

nd

s.

Wa

terb

od

y i

s co

nsi

de

red

pro

ba

bly

at

risk

of

dif

fuse

sou

rce

po

llu

tio

n a

s a

re

sult

of

nu

trie

nt

nit

rog

en

, a

nd

fro

m p

hy

sica

l o

r

mo

rph

olo

gic

al

alt

era

tio

n a

s

a r

esu

lt f

rom

sh

ore

lin

e

stru

ctu

res.

Wa

terb

od

y i

s

con

sid

ere

d p

rob

ab

ly a

t

risk

of

ph

ysi

cal

or

mo

rph

olo

gic

al

alt

era

tio

n a

s a

re

sult

of

dre

dg

e s

po

il

rep

lace

me

nt.

It

is a

lso

con

sid

ere

d p

rob

ab

ly a

t

risk

fro

m i

nv

asi

ve

spe

cie

s.

Wa

ter

Bo

dy

Pro

ba

bly

no

t

at

risk

- D

iffu

se S

ou

rce

Urb

an

& T

ran

spo

rt

Pre

ssu

re

Dri

nk

ing

, W

ate

r

an

d A

bst

ract

ion

.

N

ote

– t

ext

in

re

d i

nd

ica

ted

WF

D f

ail

ure




2.4.0.3 The WFD baseline information in Table 2.1 shows that, overall the Swansea Bay Coastal

Waterbody is failing under the WFD, on the basis of phytoplankton and dissolved

inorganic nitrogen. The Swansea Carboniferous Coal Measures, the Neath Estuary, Tawe

Estuary and Bristol Channel Outer North Coastal Waterbody are meeting the WFD

objective of Good Status.

2.4.0.4 In the context of the WAPs, Swansea Bay is considered to be at risk of failing to meets its

WFD objectives as a result of enhanced levels of nutrient nitrogen, and also because of

coastal morphological changes, due to shoreline structures. This is likely because of the

urbanised nature of the land surrounding Swansea Bay, including the conurbations of

Swansea and Port Talbot.

WFD Mitigation Measures for Waterbodies

2.4.0.5 Information in Appendix B of the Western Wales RBMP (Waterbody status objectives)

suggests that all relevant mitigation measures are in place for the Neath Estuary and

Tawe Estuary. However, the current WFD failure at Swansea Bay means that there is a

number of mitigation measures which are not in place in respect of this waterbody , as

set out in Appendix B of the RBMP. These mitigation measures, should they be

implemented, could improve the WFD status of the waterbody. The mitigation measures

are:

a. Indirect / offsite mitigation (offsetting measures);

b. Alter timing of dredging / disposal;

c. Reduce sediment resuspension;

d. Reduce impact of dredging;

e. Prepare a dredging / disposal strategy;

f. Avoid the need to dredge (e.g. minimise under-keel clearance; use fluid mud

navigation; flow manipulation or training works);

g. Operational and structural changes to locks, sluices, weirs, beach control, etc;

h. Preserve and where possible enhance ecological value of marginal aquatic habitat,

banks and riparian zone;

i. Managed realignment of flood defence;

j. Bank rehabilitation / reprofiling;

k. Preserve and, where possible, restore historic aquatic habitats;

l. Removal of hard bank reinforcement or replacement with soft engineering solution;

and

m. Remove obsolete structure.

2.4.0.6 The Project has been designed to take into consideration the requirements of the WFD.

The following mitigation measures and enhancements are proposed to reduce overall

potential effects of the project through all of its life stages and to provide benefits to the

WFD waterbodies status where relevant to the Project. Further mitigation measures will

be developed where appropriate during the EIA:




i. All construction works would be undertaken in accordance with relevant legislation

and good practice guidance for the protection of surface and groundwater, which

would ensure that there is no degradation in WFD objectives during the construction

phase;

ii. Construction site drainage would be carefully designed and controlled, with silt traps

established at the outset of the works, which would ensure that there is no

degradation in WFD objectives during the construction phase;

iii. It would be proposed that, prior to construction of the Offshore Works commencing,

invasive species would be removed as far as practical from within the footprint of the

Offshore Works. This would offer net benefits to the WFD waterbodies. These

presence of invasive species would be identified as part of the benthic survey, and an

invasive non-native species (INNS) management plan would be implemented during

the construction phase;

iv. The re-introduction of native oyster to the area would be encouraged, which would

offer benefits to the WFD waterbodies;

v. New rocky reef would be incorporated into the proposed development, which would

offer benefits to the WFD waterbodies;

vi. It is proposed that a lobster hatchery be developed and lobsters be introduced onto

the rocky reef, which would offer benefits to the WFD waterbodies;

vii. Opportunities for fisheries would be investigated, which would offer benefits to the

WFD waterbodies. At present, this would include the new reef habitat that will be

provided as part of the development;

viii. Options for reducing the potential effects of the intermittent storm discharge through

the existing outfall are being investigated. This would provide improvements to

bathing water quality and Shellfish Waters Directive4; and

ix. Potential introduction of surface “soft” landscaping within the existing coastal rock

armouring.

2.4.0.7 Further opportunities for enhancement measures, for example draped dunes and

saltmarsh, will be investigated during the EIA phase of the project.

2.5 Relationship of the Proposed Development to relevant WFD Waterbodies (Stage 3)

2.5.0.1 This section provides more information about the components of the proposed

development and their relationship to the WFD waterbodies included in this assessment.

This section determines whether the components of the proposed development have

potential to affect the WFD objectives of the five waterbodies.

2.5.0.2 Where the components of the proposed development are relevant to the WFD's

objectives, those components are taken forward to Stage 4 of this assessment

(Preliminary Assessment). If the components of the proposed development are not

considered relevant to the WFD, they are not taken forward to Stage 4 and are screened

out at this stage.

2.5.0.3 Table 2.2 presents further details of the elements associated with the proposed

development and their relationships with the WFD waterbodies identified above.

4 The European Community Shellfish Waters Directive (2006/113/EC)

T

ida

l La

go

on

Sw

an

sea

Ba

y p

lc

Tid

al L

ag

oo

n S

wa

nse

a B

ay

Wa

ter

Fra

me

wo

rk D

ire

ctiv

e S

cre

en

ing

P

ag

e 1

6

Ta

ble

2.2

Re

lati

on

ship

of

the

Pro

ject

co

mp

on

en

t w

ith

re

lev

an

t W

FD

wa

terb

od

ies

De

ve

lop

me

nt

Co

mp

on

en

t

An

tici

pa

ted

wo

rks

wit

hin

/ d

ire

ctly

ad

jace

nt

to W

FD

Wa

terb

od

ies

De

tail

s /

Co

mm

en

ts

Re

lev

an

t to

WF

D?

Lag

oo

n w

all

s.

Co

nst

ruct

ion

a

nd

lo

ng

te

rm p

rese

nce

of

Lag

oo

n w

all

s w

ith

in t

he

Sw

an

sea

Ba

y

Co

ast

al

Wa

terb

od

y a

nd

Ca

rbo

nif

ero

us

Co

al

Me

asu

res.

Pa

rtly

ad

jace

nt

to t

he

Bri

sto

l C

ha

nn

el

Ou

ter

No

rth

Co

ast

al

Wa

terb

od

y,

Ne

ath

Est

ua

ry a

nd

Ta

we

Est

ua

ry.

Co

nst

ruct

ion

in

volv

es:

• D

red

gin

g t

o p

rovi

de

se

dim

en

t fi

lle

d

ge

ote

xtil

e t

ub

es;

• D

red

gin

g t

o p

rovi

de

an

in

fill

of

sed

ime

nt,

fro

m t

he

la

go

on

fo

otp

rin

t; a

nd

• O

ute

r p

rote

ctio

n o

f ro

ck a

rmo

ur

of

vari

ou

s

gra

de

s.

Pre

sen

ce o

f la

go

on

wa

lls

wil

l a

lte

r co

ast

al

pro

cess

es

an

d t

he

refo

re a

ffe

ct e

xist

ing

hy

dro

mo

rph

olo

gy

.

Ye

s –

con

stru

ctio

n o

f la

go

on

wa

lls

wo

uld

ha

ve

po

ten

tia

l sh

ort

-te

rm i

mp

act

on

its

ch

em

istr

y a

nd

bio

log

y.

Pre

sen

ce o

f w

all

s d

uri

ng

op

era

tio

n

wo

uld

ha

ve a

po

ten

tia

l lo

ng

-te

rm i

mp

act

on

th

e

hy

dro

mo

rph

olo

gy

an

d b

iolo

gy

of

the

Sw

an

sea

Ba

y C

oa

sta

l W

ate

rbo

dy

.

No

eff

ect

an

tici

pa

ted

on

Ca

rbo

nif

ero

us

Co

al

Me

asu

res

Gro

un

dw

ate

r.

Tu

rbin

e h

ou

sin

g,

inle

t ch

an

ne

ls a

nd

sco

ur

pro

tect

ion

.

Co

nst

ruct

ion

an

d o

pe

rati

on

wit

hin

th

e

Sw

an

sea

Ba

y C

oa

sta

l W

ate

rbo

dy

.

Th

e t

urb

ine

s a

nd

slu

ice

ga

tes

wo

uld

be

ho

use

d w

ith

in t

his

co

mp

on

en

t, w

hic

h i

s to

be

loca

ted

in

th

e s

ou

th w

est

ern

po

int

of

the

bre

ak

wa

ter

wa

ll.

Th

e h

ou

sin

g w

ou

ld b

e u

p t

o

55

0m

lo

ng

an

d i

s cu

rre

ntl

y e

xpe

cte

d t

o h

ou

se

be

twe

en

16

– 2

2 t

urb

ine

s.

Th

e t

urb

ine

ho

usi

ng

wil

l b

e t

he

ma

in

exc

ava

tio

n o

f th

e s

ea

be

d w

ith

th

e i

nle

t

cha

nn

els

on

th

e g

rad

ien

t le

ad

ing

do

wn

to

it.

Sco

ur

pro

tect

ion

wil

l b

e p

lace

d i

n t

his

are

a.

Ye

s –

co

nst

ruct

ion

on

th

e s

ea

be

d w

ill

ha

ve a

po

ten

tia

l sh

ort

-te

rm i

mp

act

on

its

ch

em

istr

y.

Th

ere

wil

l b

e a

po

ten

tia

l lo

ng

-te

rm i

mp

act

on

th

e

hy

dro

mo

rph

olo

gy

an

d b

iolo

gy

of

the

Sw

an

sea

Ba

y C

oa

sta

l W

ate

rbo

dy

, d

uri

ng

th

e o

pe

rati

on

al.

Alt

ho

ug

h u

nli

ke

ly (

Ch

ap

ter

18

of

the

PE

IR)

po

ten

tia

l e

ffe

ct o

n s

alt

we

dg

e a

nd

Ca

rbo

nif

ero

us

Co

al

Me

asu

res

Gro

un

dw

ate

r w

ill

be

fu

rth

er

inve

stig

ate

d.

Lag

oo

n w

ate

r a

rea

/ o

ffsh

ore

pu

bli

c

rea

lm.

Co

nst

ruct

ion

an

d o

pe

rati

on

ad

jace

nt

to

an

d w

ith

in t

he

Sw

an

sea

Ba

y C

oa

sta

l

Wa

terb

od

y,

an

d a

dja

cen

t to

th

e T

aw

e

Est

ua

ry.

Th

is a

rea

wo

uld

be

a w

ate

rsp

ort

ve

nu

e,

wit

hin

th

e l

ag

oo

n w

all

s, a

s th

ey

wo

uld

pro

vid

e a

sa

fe b

od

y o

f w

ate

r.

No

– a

s th

ere

wil

l b

e m

inim

al

con

stru

ctio

n w

ith

in

the

wa

terb

od

ies,

be

st p

ract

ice

po

llu

tio

n

pre

ven

tio

n b

ein

g d

ep

loy

ed

wo

uld

mit

iga

te a

ny

po

ten

tia

l im

pa

ct.

Em

erg

en

cy f

aci

liti

es

an

d s

lip

wa

ys

(on

sho

re a

nd

off

sho

re).

Co

nst

ruct

ion

an

d o

pe

rati

on

wit

hin

th

e

Sw

an

sea

Ba

y C

oa

sta

l W

ate

rbo

dy

.

Th

ese

fa

cili

tie

s w

ou

ld h

ou

se e

me

rge

ncy

bo

ats

wit

h s

lip

wa

y a

cce

ss,

on

e b

ase

d o

n t

he

we

ste

rn s

ide

of

the

la

go

on

an

d p

ote

nti

all

y

on

e o

n t

he

ea

ste

rn s

ide

.

No

– a

ny

co

nst

ruct

ion

wit

hin

th

e S

wa

nse

a B

ay

Co

ast

al

Wa

terb

od

y w

ill

pri

ma

rily

be

on

th

e

lag

oo

n w

all

s (c

on

sid

ere

d s

ep

ara

tely

ab

ove

).

Op

era

tio

n a

nd

ma

inte

na

nce

faci

liti

es,

bo

ati

ng

cen

tre

/ vi

sito

rs

Co

nst

ruct

ion

an

d o

pe

rati

on

wit

hin

th

e

Ta

we

Est

ua

ry W

ate

rbo

dy

an

d a

dja

cen

t to

the

Sw

an

sea

Ba

y C

oa

sta

l W

ate

rbo

dy

.

Loca

ted

on

th

e w

est

ern

sid

e o

f th

e l

ag

oo

n,

ad

jace

nt

to t

he

la

nd

.

No

– m

inim

al

con

stru

ctio

n a

dja

cen

t to

wa

terb

od

y,

tho

ug

h l

oca

lise

d t

em

po

rary

dre

dg

ing

to a

llo

w a

cce

ss a

t a

ll s

tate

s o

f ti

de

. T

his

dre

dg

ing

wil

l b

e a

sse

sse

d w

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he

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by

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on

stru

ctio

n w

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th

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ly i

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all

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on

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lls

so l

imit

ed

imp

act

s a

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n W

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wa

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rse

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aw

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on

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info

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de

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, p

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act

(Ch

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of

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IR f

or

Gro

un

dw

ate

r).




2.5.0.4 The information in Table 2.2 demonstrates those components of development

considered to potentially be relevant to the WFD objectives of the relevant waterbodies,

and these are:

a) Lagoon Walls (construction and operation); and

b) Turbine Housing with Inlet Channels and Scour Protection (construction and

operation).

2.5.0.5 These components are therefore screened into the preliminary assessment and are taken

forward to Stage 4.

2.5.0.6 All other components of the proposed development are screened out of the preliminary

assessment, and not taken forward for assessment at Stage 4, as it is not considered that

they could inhibit the waterbodies included within the study area achieving, or continuing

to achieve, the WFD objectives.

2.6 WFD Preliminary Assessment (Stage 4)

2.6.0.1 This section reports the preliminary assessment. It assesses each component of the

proposed development that has been identified as being relevant to the WFD against the

waterbodies comprised in the study area. The assessment has been undertaken on the

basis of whether the works undertaken as part of the Project are likely to result in:

1. Failure to achieve, good ecological status or good ecological potential within the

waterbody;

2. Failure to prevent any deterioration in groundwater status, ecological status or

ecological potential within the waterbody;

3. Permanent exclusion of, or compromised achievement of, WFD objectives in the

waterbody (or other waterbodies);

4. Non-compliance or compromised implementation of other EU legislation; and

5. Prevention of the waterbody in meeting any of the mitigation measures specified in

the RBMP, either now or in the future.

2.6.0.2 In general, construction of the Project will have a temporary effect on the surrounding

environment, for example impacts in respect of noise and increased suspended solids.

However, there would be longer term effects associated with construction, such as

permanent loss of habitat beneath the footprint of the proposed development. During

operation, longer term effects are anticipated, some negative and others potentially

positive.

2.6.0.3 An assessment of the components of the Project (identified in Table 2.2 above) will be

undertaken for both the construction and operation phase. The results of these

assessments are presented in Table 2.3 and Table 2.4 respectively. These tables provide a

matrix of the potential effects of those screened in components of the proposed

development against the WFD Elements for Transitional, Coastal and Ground Water

bodies, as listed in the relevant section of River Basin Management Plan Western Wales

River Basin District Annex B: Water body status objectives WFD.




Table 2.3 Preliminary Assessment of Project components against WFD elements during

construction

WFD Elements Lagoon Walls Turbine Housing, Inlet Channels &

Scour Protection

Biological Quality

Elements

(comprising

phytoplankton,

other aquatic flora

(macrophytes and

phytobenthos),

benthic invertebrate

fauna and fish

fauna)

Swansea Bay, Bristol Channel

Outer North, Tawe Estuary, Neath

Estuary

Temporary noise, vibration and re-

suspension of sediment (reducing

oxygen, releasing contaminants)

during construction of the lagoon

walls could potentially impact upon

marine ecology. Direct loss of

habitat under the footprint of the

proposed development. Further

assessment will be undertaken

during the EIA.

Swansea Bay

The construction of the turbine

housing/inlet area will require the

formation of a temporary cofferdam so

that the main works can be

undertaken in the dry. Depending on

its type (sand bund, steel cofferdam,

etc.) the temporary impacts will vary.

The potential impacts of this will be

assessed further during the EIA.

Dry construction of the turbine house

will minimise potential impacts.

The removal of the cofferdam and final

formation of the inlet channels could

impact upon the aquatic flora and

fauna, which will be identified within

the EIA. Further assessment will also

be undertaken during the EIA.

Chemical and

physico-chemical

elements

comprising:

transparency,

thermal conditions,

oxygenation

conditions, salinity,

nutrient conditions,

and specific

pollutants.

Swansea Bay, Bristol Channel

Outer North, Tawe Estuary, Neath

Estuary

Dredging for the construction of

the lagoon walls, and disturbance

of the seabed could result in

increased sediment being re-

suspended into the water column.

This sediment could contain

contaminants that would

detrimentally affect water

chemistry. Further assessment will


Swansea Bay

Depending on the option selected, the

formation and removal of the

cofferdam may have similar impact to

that of the lagoon wall, and will be

further assessed within the EIA.

The dry construction of turbine

housing/ inlet channel is not

considered likely to have any

significant impact on the chemical

status of the waterbodies during

construction, assuming best-practice

pollution control measures are

adopted.

Hydromorphological

elements

comprising:

morphological

conditions (depth

variation; quantity,

structure and

substrate of the

bed; structure of

the intertidal zone)

and tidal regime

(freshwater flow,

wave exposure).

Swansea Bay, Tawe Estuary, Neath

Estuary

The lagoon walls could potentially

alter the flow regime and

hydromorphology in Swansea Bay,

through providing an obstruction

to natural flows and coastal

processes. Further assessment will


Swansea Bay

The construction of the turbine

housing/inlet channel is not considered

likely to have significantly greater

effect on the flow regime and


than the construction of the lagoon

walls, which are considered separately.

No further assessment required.

Note – Swansea Bay currently failing WFD for phytoplankton

Note – Swansea Bay currently failing WFD for dissolved inorganic nitrogen




Table 2.4 Preliminary Assessment of components against WFD elements during operation

WFD Elements Lagoon Walls Turbine Housing/ Inlet Channels &

Scour Protection

Biological Quality

Elements

(comprising

phytoplankton,

other aquatic flora

(macrophytes and

phytobenthos),

benthic invertebrate

fauna and fish

fauna)


Estuary

During operation, although not a

barrage across the Neath or Tawe

rivers, the walls would form a

physical barrier to part of the bay

which could impact upon other

aquatic flora and fauna, through

changed flows, reduced feeding

areas and translocation of species.

Further assessment will be

undertaken during the EIA.

Swansea Bay/ Carboniferous Coal

Measures Groundwater

Noise, vibration and re-suspension of

sediment from turbine operation could

potentially impact upon marine

ecology. Although not a barrage there

is a potential for fish to come in

contact with the turbines. Small

change to tidal state within lagoon

footprint could potentially affect

saltwater wedge and groundwater.

Further assessment will be undertaken

during the EIA.

Chemical and

physico-chemical

elements

comprising:

transparency,

thermal conditions,

oxygenation

conditions, salinity,

nutrient conditions,

and specific

pollutants.


Estuary

The presence of the lagoon walls

will alter the flows around the bay.

An assessment of potential change

in water chemistry will be

undertaken in combination with

the turbine operation. Further

assessment will be undertaken

during the EIA.

Swansea Bay

The turbine operation could potentially

cause changes in flows and water

chemistry. This impact will be assessed

in conjunction with the lagoon as a

whole as part of the EIA. Any

additional measures which will be

implemented to improve water quality

within the lagoon during operation will

also be considered. Small change to

tidal state within lagoon footprint

could potentially affect saltwater

wedge and groundwater. Further

assessment will be undertaken during

the EIA.

Hydromorphological

elements

comprising:

morphological

conditions (depth

variation; quantity,

structure and

substrate of the

bed; structure of

the intertidal zone)

and tidal regime

(freshwater flow,

wave exposure).


Estuary

The lagoon walls could potentially

alter the flow regime and


through providing an obstruction

to existing flows and coastal

processes. Further assessment will


Swansea Bay

The turbine housing will generate

increased currents in its vicinity which

could cause localised scour. Although

localised, it will be considered further

during the EIA. Further assessment will

be undertaken.

Note – Swansea Bay currently failing WFD for phytoplankton

Note – Swansea Bay currently failing WFD for dissolved inorganic nitrogen

2.6.0.4 Those interactions between the Project and the surrounding WFD waterbodies which are

considered to pose a risk to the achievement of the objectives of the WFD in respect of

the relevant waterbody/waterbodies are highlighted in red in Tables 2.3 and 2.4 above.

These components of the Project and interactions will, therefore, be taken forward to

Stage 5, where they are subject to more detailed assessment of their impact upon the

WFD waterbodies.




2.6.0.5 Stage 5, detailed assessment, will be undertaken during the EIA and reported in the

Environmental Statement submitted with the application for development consent for

the project.

WFD Mitigation Measures Assessment

2.6.0.6 The WFD states that development should not inhibit the achievement of any of the

mitigation measures that could be implemented to enable a waterbody to achieve its

WFD objectives (RBMP Annex B: Water body status objectives). As outlined above, in

Section 2.3.0.5, the Western Wales RBMP includes a series of mitigation measures

relating to Swansea Bay Coastal waterbody. These are not in place, but could be

implemented to ensure that the waterbody achieves its WFD objectives. These mitigation

measures are considered below, in relation to the Project. Where potential conflicts

between the Project and implementation of the RBMP mitigation measures occur, these

are highlighted in red, and where mitigation measures are supported by the proposed

development, these are shown in green. Swansea Bay mitigation measures which are not

affected or are not relevant to the proposed development are shown by strike through:

a) Indirect / offsite mitigation (offsetting measures);

b) Alter timing of dredging / disposal;

c) Reduce sediment resuspension – The Project intends to use dredged material from

Swansea Bay, within the tidal lagoon area, to construct the lagoon walls. During the

construction phase this dredging will cause resuspension of sediment from the seabed

although the geotubes will reduce this compared to normal dredging practices. This

will be further examined during the EIA process;

d) Reduce impact of dredging - The Project intends to use dredged material from

Swansea Bay, within the tidal lagoon area, to construct the lagoon walls – this would

be a temporary, construction phase effect. During operation of the project the effect

on the current dredging practices in Neath, Tawe and Port Talbot channels would be

reviewed as part of the EIA process;

e) Prepare a dredging / disposal strategy - the need for this during the operation phase

would be based on the findings of the EIA;

f) Avoid the need to dredge (e.g. minimise under-keel clearance; use fluid mud

navigation; flow manipulation or training works);

g) Operational and structural changes to locks, sluices, weirs, beach control etc;

h) Preserve and where possible enhance ecological value of marginal aquatic habitat,

banks and riparian zone – will be considered as part of any bank side river works;

i) Managed realignment of flood defence;

j) Bank rehabilitation / reprofiling;

k) Preserve and, where possible, restore historic aquatic habitats – opportunities for

improvements here associated with Port Rock armour intertidal habitat;

l) Removal of hard bank reinforcement or replacement with soft engineering solution –

Lagoon walls are to be rock-armoured, and scour protection is to be employed around

the turbine housing (underwater). The former is therefore extensions of the hard bank

reinforcement. However, it is proposed that there will be some softening of the

existing sea defence rock armour, through the provision of draped dunes etc. which

could result in benefits;

m) Remove obsolete structure - although not obsolete, the removal of the existing 2m

high seawall along the Port eastern breakwater is being considered with it being

replaced with marine landscaping. Although this wall is understood not to be part of

any flood protection, it does provide wave/spray shelter. The offshore lagoon wall and




reduction in fetch should replace this function, thereby allowing this coastal stretch to

be improved.

2.6.0.7 The potential adverse effect of the proposed development on those mitigation measures

highlighted in red above will be taken forward to Stage 5 for detailed assessment.

Cumulative Impact Assessment

2.6.0.8 The scoping work undertaken for the EIA has identified a list of developments proposed

within the local area that should be reviewed in terms of cumulative effects. These

developments are shown below in Table 2.5, and a preliminary screening has been

undertaken to identify those which will be considered further in terms of the WFD during

the EIA process.

Table 2.5 Preliminary assessment of cumulative sites

Project and location Current Status Preliminary WFD Assessment

Swansea Bay Science and

Innovation Campus, adjacent to

Crymlyn Burrows.

Planning permission granted,

construction Feb 2013 – Sept

2015.

Potential positive impacts in

terms of WFD objective, from a

flood risk perspective, through

encompassing the shoreline

within the tidal lagoon. Further

consideration during EIA. Further

assessment required.

St Modwens land development

- East of port to west of Neath

estuary.

Remediation of land, and

potential future developments

– no details available.

Works anticipated to be

complete – no cumulative impact

anticipated.

Mumbles pier, foreshore and

coastal strip redevelopment

Due to be redeveloped by the

end of 2013.

Works anticipated to be

complete – no cumulative impact

anticipated.

Construction of new RNLI

Lifeboat Station, Mumbles

Expected completion 2014. Works anticipated to be

complete – no cumulative effect

anticipated.

SA1 development Development currently taking

place. Completion date

unknown.

Works shore based – no

cumulative impact anticipated.

Construction of the Southern

Access Road to Coed Darcy

Urban Village, crossing nearby

Crymlyn Bog.

Nearing completion. Works distant and shore based –

no cumulative impact

anticipated.

Swansea Boulevard project-

work between Princess way and

the Strand, and the River Tawe

bridges and The Strand.

First phase to be complete in

November 2013. Second phase

to start 2014 - working to a

similar timescale.

Works shore based – no


Wind turbine - on Welsh water

site on Fabian Way.

Status unknown Works shore based – no


5 wind turbines - at Mynydd

Marchywel between Rhos and

Cilfrew Neath

Submitted Jan 2012.

Consultation finished Jan 2013.

Still in planning.

Works distant – no cumulative

impact anticipated.

16 wind turbines - at Mynydd Y

Gwair, Swansea

Approved – unknown

construction timetable.


impact anticipated.

5 wind turbines - on land at

Mynydd Brombil Farm,

Margam, Port Talbot

Submitted June 2012, still in

planning. Consultation finishes

April 2013.


effect Works distant and shore

based – no cumulative impact

anticipated.

Atlantic Array Wind Farm – off

North Devon Coast approx

DCO application not submitted.

Construction timetable

Works distant and shore based –

no cumulative impact




35km distant. unknown. anticipated.

76 turbine Pen y Cymoedd

windfarm near Neath.

Planning approved –

construction 2014


impact anticipated.

15 turbine windfarm - on land

500m South West of

Cynnonville Port Talbot

Status Unknown Works distant – no cumulative

impact anticipated.

Port Talbot Harbour

Redevelopment.

Potential future activities/

Development. Status unknown.

Status and need for assessment

will be reviewed in EIA.

Upgrading of existing coastal

defence of Aberavon West

Promenade, Sandfields, Port

Talbot

Status Unknown Increased rock armour. Further

detail sought for EIA and if

available further assessment.

Porthcawl regeneration scheme

Plans include Porthcawl Marina

project.

Approved - Timescale unknown. Works distant– no cumulative

impact anticipated.

Underground coal gasification

under Swansea Bay.

License issued No cumulative impact

anticipated.

Navigational dredging Tawe,

Neath and Port Talbot.

Existing/proposed dredging in

Bristol Channel.

On-going Potential cumulative impacts will

be considered further in the EIA.

Marina dredging - Monkston

cruising and sailing club and

Swansea Marina

On-going Maintenance

dredging

Potential cumulative impacts will

be considered further in the EIA.

Severn Barrage Timescale unknown. High level review to be

undertaken.

Swansea Barrage Operational Currently operational – no

cumulative impacts anticipated.

Cardiff Barrage Operational Project distant and currently

operational – no cumulative

impact anticipated.

Baglan Power station Operational No cumulative impact

anticipated.

2.6.0.9 Those developments that could cumulatively effect the waterbodies and inhibit them

from achieving their WFD objectives are highlighted in red in the above table. A

consideration of those developments will form part of the detailed assessment at Stage 5.

2.7 WFD Detailed Assessment (Stage 5)

2.7.0.1 Those interactions and potential impacts identified for further assessment as part of the

WFD preliminary assessment will be considered during the WFD Detailed Assessment.

This assessment will be undertaken through the EIA process.

Tidal Lagoon Swansea Bay Plc



APPENDIX 1

Water Framework Directive Article 4.7

Tidal Lagoon Swansea Bay Plc



‘Member States will not be in breach of this Directive when:

- failure to achieve good groundwater status, good ecological status or, where relevant, good

ecological potential or to prevent deterioration in the status of a body of surface water or

groundwater is the result of new modifications to the physical characteristics of a surface water

body or alterations to the level of bodies of groundwater, or

- failure to prevent deterioration from high status to good status of a body of surface water is the

result of new sustainable human development activities and all the following conditions are

met:

(a) all practicable steps are taken to mitigate the adverse impact on the status of the body of

water;

(b) the reasons for those modifications or alterations are specifically set out and explained in

the river basin management plan required under Article 13 and the objectives are reviewed

every six years;

(c) the reasons for those modifications or alterations are of overriding public interest and/or

the benefits to the environment and to society of achieving the objectives set out in

paragraph 1 are outweighed by the benefits of the new modifications or alterations to

human health, to the maintenance of human safety or to sustainable development, and

(d) the beneficial objectives served by those modifications or alterations of the water body

cannot for reasons of technical feasibility or disproportionate cost be achieved by other

means, which are a significantly better environmental option.’

23.0 tidal lagoon swansea bay

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