Environment Agency Title
Mersey Warrington
Flood Risk Management Scheme
Environmental Statement
Non-Technical Summary December 2011
Mersey Warrington Environmental Statement Flood Risk Management Scheme Non-Technical Summary
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1 Introduction
1.1 The Environment Agency has submitted a planning application to
Warrington Borough Council to construct a Flood Risk Management Scheme
(FRMS).
1.2 The proposed FRMS would reduce the risk of flooding to people, property
and the environment to a to 1% change of flooding in any one year to the
Howley, Latchford, Padgate, Bruche and Woolston areas of Warrington,
Cheshire.
Location of Proposed Development
1.3 The proposed development comprises the construction of approximately
5km of flood wall and 2.2km of embankment at discrete locations along the
River Mersey corridor between Woolston and Bridgefoot roundabout, along
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Padgate Brook at Orford Road and The Twiggeries, and along Spittle Brook
at Cinnamon Brow.
The Purpose and Structure of this Non-Technical Summary
1.4 An Environmental Statement (ES) has been prepared to accompany the
planning application for the FRMS. The ES describes the potential positive
and negative impacts of the proposed development and describes how any
adverse impacts are to be addressed.
1.5 This Non-Technical Summary (NTS) provides a summary of the ES and is
structured as follows:
Chapter 2 – Background to the Proposed Development;
Chapter 3 - Description of the Proposed Development; and
Chapter 4 - Summary and Conclusions.
1.6 The planning application is also accompanied by a:
Planning Application Supporting Statement;
Design Guide; and
Flood Risk Assessment.
Contact Details
1.7 If you would like any further information or wish to discuss the contents of
this document further please contact either:
Chris Stone, Project Manager, on 01925 542419
Jennifer Craig, Environmental Project Manager, on 01925 542373
Or write to them at:
Mersey Warrington FRMS
Environment Agency
Richard Fairclough House
Knutsford Road
Warrington
Cheshire
WA4 1HG
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Or via email at: [email protected]
1.8 If you have any comments relating to the planning application these should
be directed to the Development Control team at Warrington Borough
Council.
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2 Background to the Proposed Development
2.1 This section describes the reasons why we propose to build a flood risk
management scheme in Warrington, the options that were considered and
why the proposed scheme was chosen.
2.2 Drawing IMNW000699/GEN/ENV/001 shows the location of the proposed
development in the wider strategic context and key locations and features
referred to below.
Flood Risk in Warrington
2.3 The over-arching objective of Mersey Warrington FRMS is ‘To deliver a
comprehensive scheme to manage the risk to people, property and the
environment from flooding over the next 100 years’.
2.4 Warrington is at risk of flooding from high tides rising up the River Mersey
and from river flows from the River Mersey, Padgate and Spittle Brooks.
Our flood risk maps for Warrington identify approximately 4,000 properties
as being at a 1% chance of flooding in any one year across the town. In
2009, the National Flood Risk Assessment showed that Warrington had the
10th highest number of properties at significant risk of flooding in the country.
2.5 In order to assess the risk of flooding in the study area, a computer model
was developed. This showed that over 624 residential properties and 28
industrial/ commercial properties are at a 5% chance of flooding in any one
year, rising to 2,129 residential properties and 123 industrial/commercial
properties from a 1% annual chance of flooding.
2.6 In February 1990 a high tide resulted in flooding in the Lower Walton,
Knutsford Road and Westy areas affecting 17 residential properties,
approximately 8,000m2 of commercial floor space and a secondary school.
2.7 Further flooding occurred in 1998 and localised flooding of roads and low-
lying areas in tidal reaches were recorded during October/November 2000,
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with high tides in February 2002 and March 2006 also coming close to
flooding the Knutsford Road area. Typically, the River Mersey will overtop
its banks every year at the highest annual tides.
2.8 The existing flood walls within Warrington offer varying standards of
protection, estimated as providing up to 1 in 20 year standard.
The Strategic Approach and Alternative Options Considered
2.9 The proposed development is the result of a series of studies assessing the
feasibility and justification for a project to reduce the risk of flooding.
2.10 The Mersey Estuary Catchment Flood Management Plan was published in
December 2009. This study identified the proposed scheme area as being
within a wider area of moderate to high risk of flooding and that further
action should be taken to reduce flood risk. A key action from the plan was
the development of a Flood Risk Management Strategy to improve the
understanding of flood risk in the Warrington area and how it could be
addressed.
2.11 The Warrington Flood Risk Management Strategy was published in January
2010. This also considered a wider area than the proposed scheme.
Following detailed investigations of all options to manage flood risk, we
shortlisted three options:
i) Building of flood walls and embankments;
ii) Removing Howley Weir and building of flood walls and embankments,
albeit to a lesser height than option (i); and
iii) Building a tidal barrier across the River Mersey and flood walls and
embankments to a lesser height than option (i).
2.12 Following an appraisal of the consultation feedback, technical constraints,
the cost of each option and potential impacts on the environment, option (i)
was identified as the preferred option.
2.13 Variations of building flood walls and embankments were appraised during
the Project Appraisal Report (June 2011). The study developed an outline
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scheme and provided an assessment of the costs and benefits to support a
business case for the scheme.
2.14 The variations were generally different alignments of defences and different
types of construction methods. As a general principle, earth embankments
were preferred where physical space and ground conditions allowed.
Elsewhere floodwalls were proposed. Where technically feasible, reinforced
concrete floodwalls are preferred; sheet pile floodwalls are proposed only
where ground conditions and/or space constraints prevent alternative
construction methods.
2.15 The preferred scheme was determined through a comparison of the
potential impacts based on the professional judgement and experience of
the appraisal team comprising engineering, operational, planning and
environmental specialists.
2.16 The proposed Flood Risk Management Scheme (FRMS) was approved by
the Environment Agency’s internal review group in November 2011.
2.17 The proposed scheme excludes two areas identified during the Mersey
Warrington Project Appraisal Report:
i) Along Howley Lane between Howley Sub-station and Holmsfield
Road; and
ii) Between Mersey Walk and Kingsway North, referred to as the Westy
area.
2.18 Both these areas are being built by other developers. The works adjacent to
Howley Lane are already being built. With respect to the works in the Westy
area the developer is proposing to submit a planning application to build
flood structures in parallel to their development. Their proposals have been
developed through liaison with the Environment Agency and would reduce
the risk of flooding to the same standard of protection as the proposed
Mersey Warrington FRMS.
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3 Description of the Proposed Development
3.1 The proposed development is generally located on land adjacent to or within
the River Mersey corridor between Woolston and Bridgefoot Roundabout,
and at various locations along Padgate and Spittle Brooks, specifically:
River Mersey – from Woolston Weir to Bridgefoot Roundabout;
Padgate Brook - at Orford Road;
Padgate Brook – from The Twiggeries to the confluence with the River
Mersey; and
Spittle Brook – at Cinnamon Brow.
3.2 For the purposes of appraising the environmental impacts of the scheme the
study area extends beyond the river corridor adjacent to these
watercourses, dependent on the nature of the impact and the receptor
(person and/or environmental feature potentially affected).
3.3 Subject to receiving the necessary planning permission, funding approvals
and other consents, it is proposed to start building Phase 1 in October 2012.
3.4 The proposed development is to be built in three phases:
Phase 1 – River Mersey (south bank) from Kingsway Bridge to
Bridgefoot roundabout, including Victoria Park;
Phase 2 – River Mersey (north bank) from Kingsway Bridge to
Bridgefoot roundabout; and
Phase 3 – River Mersey from Kingsway Bridge to Woolston including
works along Padgate Brook at Orford Road and from The
Twiggeries to the River Mersey, and along Spittle Brook at
Cinnamon Brow.
3.5 We expect that all three phases would be built within 3 years, ending in
September 2015.
3.6 The indicative landscape plans (see drawings IMNW000699/GEN/ILP/001 to
008) accompanying this Non-Technical Summary provide the key features of
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the proposed development and should be read alongside the following text.
For a full description of the works, refer to the main Environmental
Statement.
Phase 1
3.7 Phase 1 is approximately 1.28km of new flood embankments and 350m of
flood walls to heights typically up to 1.5m above the adjacent ground level,
with localised heights up to 1.8m.
3.8 A combination of new flood wall and embankment would be built from Black
Bear Park to the rear of commercial/industrial properties on Knutsford
Road/Black Brook Place, and along the Knutsford Road boundary of Victoria
Park to a new, relocated, park entrance.
3.9 The new Victoria Park entrance would be a semi-circular flood wall with 2-
way vehicle access and revised vehicle/pedestrian access to and within the
park.
Artist Impression of Victoria Park Entrance
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3.10 The relocated park entrance would require changes to the existing road
layout including the relocation of the Victoria Park bus stop and layby,
relocation of the pedestrian crossing and central reservation.
3.11 Within the park, there would be a new road connecting with Weir Lane
between the Bowling Green and Council’s depot, and a new access road to
the allotments.
3.12 A new flood wall would be built behind the existing electricity sub-station to
the west of the park entrance, creating a compound with separate vehicle
access to Knutsford Road.
3.13 Weir Lane would be permanently closed to vehicles. Access would be either
via the new park entrance or for pedestrians by steps over the new flood
wall.
3.14 The flood wall would extend from Victoria Park, along Knutsford Road to the
open space near Halfords Autocentre. At Howley Weir the path would be
locally widened to form a viewing platform, overlooking the river.
Photomontage along Knutsford Road at completion (excludes artwork)
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3.15 A new flood wall would be built within the River Mersey to the rear of
commercial properties/open spaces on Knutsford Road to Bridgefoot
roundabout to a height of 1.1m, The wall behind commercial properties
would have security fencing on top to a height of 2.0m and the wall behind
open spaces would have railings on top to a minimum height of 1.4m above
ground level.
3.16 Other works include the demolition of the lean-to extension at the rear of
Halfords Autocentre (73 Knutsford Road) to provide a safe working area for
construction and its subsequent rebuilding. Rock armour would be placed at
the foot of the riverbank at between Howley Weir and Bridgefoot
roundabout.
Phase 2
3.17 Phase 2 is approximately 2.03km of new flood wall and 120m of flood
embankment to heights typically up to 1.3m above the adjacent ground
level.
3.18 A new flood embankment would be built to the rear of the Warrington
Rowing Club to a height of 0.35m.
3.19 A new flood wall would be built over the Padgate Brook bridge (new course)
and new control structure within the river. The flood wall would be extended
to link with the new flood wall around the Howley Lane electricity sub-station
and steps built to maintain pedestrian access along the banks of Padgate
Brook.
3.20 Around the Howley Lane electricity sub-station, a new flood wall would be
built to a maximum height of 2.08m locally increasing the standard of
protection against flooding to a 0.1% chance of flooding in any one year.
The increased standard of protection resulted from additional contributions
from the landowner/ utility provider. A ramp with flood gate would provide
vehicle access to the sub-station from Howley Lane and steps built to
provide emergency pedestrian egress.
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3.21 A new flood wall would be built between Farrell Street and the Howley
Suspension Bridge ranging in height from 0.15m to 0.86m, with localised
ramps over the wall to maintain access. Other works include works to the
Padgate Brook (old course) and a control structure within the river, the
backfilling of the disused spillway at Howley Lane and structures to enable
water trapped on the dryside of the wall to drain back into the river.
3.22 A new flood wall would be built from the Howley Suspension Bridge to the
rear of the riverside path (Mersey Way) to the Riverside Retail Park on
Wharf Street ranging in height from 0.25m to 1.24m height above ground
level, with ramps over the wall to maintain access. Other works include
modifications to existing fire escape steps from properties on the Wharf
Street industrial estate and localised building up of the road surface by
approx. 0.3m at the Wharf Street/Vernon Street junction.
Phase 3
3.23 Phase 3 is approximately 2.0km of new flood wall and 1.5km of flood
embankment to heights typically up to 1.4m above the adjacent ground
level.
3.24 A new flood wall would be built to the rear of properties along Weir
Lane/Edward Gardens up to a height 1.4m above ground level with
pedestrian access to riverside footpath via new steps and new close
boarded fencing to a height of 1.8m above ground level to provide security
to properties. The new flood wall would run along the riverside track south
of the disused New Cut Canal at a height of 0.4m to 0.93m above ground
level with access steps and vehicle floodgate to reinstate paths. A short
length of flood embankment, to a height of 0.87m to 2.08m above ground
level would be constructed within open ground adjacent to Woolston Weir
with ramps to reinstate paths.
3.25 A new flood wall would be built to a height of 1.10m above ground level to
the rear of properties on Bridge Lane Industrial Estate with earth
embankment and ramp connecting to existing embankment to the east.
Localised ground raising would be undertaken to a height of 1.10m to the
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east of the Bridge Lane Industrial Estate to infill a low point in existing
embankment along River Mersey meander downstream of Woolston Weir.
3.26 A new flood wall would be built to a height of 0.49m to the rear of properties
on Wilkinson Avenue with new closed board fencing to a height of 1.8m
above ground level to provide security to properties. A new flood wall would
be built from Bennett Avenue to Paddington Bank to a height of 0.6m to
1.0m above adjacent ground. In addition the river bank would be stabilised
by sheet piles and localised reprofiling of the bank.
3.27 The ground level of the public open space at Paddington Bank/Kingsway
North would be raised by 0.86m with a new flood wall adjacent to a new
maintenance vehicle access. A new flood wall would extend from the public
open space to the Kingsway North allotments, to a height of 0.64m to 1.13m
above adjacent ground level with ramps over defences to provide access. A
new flood embankment would be constructed on the riverside of the
Kingsway North allotments, to a height of up to 1.0m above existing ground
level with vehicle and pedestrian access ramps over the defences.
3.28 At The Twiggeries a new 1.35m high flood embankment would be built to the
rear of properties on Kingsway North. A new river channel would be created
to connect with Padgate Brook both to the north and south and with
localised widening out to form ponds. A control structure would be built
within Padgate Brook to the north to maintain flowing water along both the
existing Padgate Brook and new river. Bridges would be built over the new
channel for footpath access. Either side of the new channel would be
planted up with reedbed to provide a new habitat. Signs would be erected to
inform members of the public that the land is liable to flooding.
3.29 At Orford Road a new 1.4m high flood embankment would be constructed to
the rear of properties to a height of 1.4m above existing ground level from
Padgate Brook/the railway line to Birchwood Way with ramps for access and
a turning head for maintenance vehicles. To the east, a new river channel
would be created, extending the open length of Padgate Brook from the
railway line north to the existing bridge crossing. Gaps would be opened up
within the existing embankment along Padgate Brook to enable the open
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space to provide floodwater storage. A new flood wall would be constructed
around the Gas High Pressure Regulator Station.
3.30 The scheme at Solway Close is a combination of flood embankment and
walls less than 600mm high, comprising embankment through Poulton Park
Golf Club, flood wall along the vehicle access track, to the rear of properties
of Solway Close, embankment between Enfield Park Road and Spittle Brook
and flood wall to the rear of properties on Enfield Park Road/St Andrews
Close.
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4 Summary and Conclusions
4.1 This section summarises the key environmental baseline conditions, the
mitigation measures that may remove or reduce any adverse impacts arising
from the proposed development, and the conclusions from the Environment
Impact Assessment for each of the environmental receptors.
Ecology
4.2 Information was gathered through a combination of desk based research,
site visits, consultation and field survey. The field survey was agreed with
WBC’s Natural Environment Officer to ensure that information was detailed
enough to assess the potential ecological impacts across all three phases of
development, whilst recognising that further survey would be required to
update these findings for phases 2 and 3 to support both detailed design
and before starting construction.
4.3 Historic fish survey data indicate greater densities of fish in the Woolston
Weir to Howley Weir stretch of the River Mersey, crossing all three phases
of the scheme. From Carrington Pumping Station to Woolston New Cut
(upstream of the scheme proposals) and from Woolston New Cut to the
freshwater limit at Howley Weir (all three phases) are designated waters
under the Freshwater Fish Directive 2006. The River Mersey is an important
route for migratory fish species between the Irish Sea and upper freshwater
reaches.
Phase 1
4.4 There are no nationally, regionally or locally important wildlife sites within or
adjacent to Phase 1. The trees and scrub areas of Victoria Park, Black Bear
Park and along the banks of the River Mersey are used by breeding birds.
However, trees were assessed as having low bat roost potential and unlikely
to support roosting bats. Two species of bats, common pipistrelle and
soprano pipistrelle were recorded during the survey, although it was
determined that the scheme had low potential for commuting and foraging
bats. Badger survey indicated presence, the details of which are available
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only on request in order to protect from persecution. The River Mersey may
be a key route through which otter re-colonise within the county; however,
no signs of otter were found during Phase 1 habitat survey, albeit all
watercourses within the catchment have potential for use by otter. There
were no signs of water vole recorded during Phase 1 habitat survey and no
records exist for water vole within the area. No populations of great crested
newt were identified during surveys.
Phase 2
4.5 There are no nationally, regionally or locally important wildlife sites within or
adjacent to the phase 2. Due to the urbanisation of the area, opportunity for
breeding birds was considered to be limited, albeit there is potential where
trees/scrub exist.
4.6 No signs of otter were found, although there is potential for their presence.
None of the features (tree/buildings etc) were confirmed as having bat
presence, although some features, notably Warrington Rowing Club
building, have moderate potential to support roosting bats. Based on
existing survey records, potential for water vole in the downstream reaches
of Padgate Brook is considered to be high and therefore a precautionary
approach has been taken during assessment. No records or indications of
badger or great crested newt were found.
Phase 3
4.7 There is one nationally designated wildlife site, the Woolston Eyes SSSI,
with potential to be affected by Phase 3, situated on the adjacent bank at
Bridge Lane Industrial and Weir Lane, Woolston. In addition, there are 3
locally designated sites: Paddington Meadows SINC, Woolston New Cut
Canal SINC and the Twiggeries SINC. Based on existing survey records,
potential for water vole in Padgate Brook is considered to be high, most
notably through The Twiggeries, at Orford Road and adjacent to Spittle
Brook at Cinnamon Brow. There is moderate opportunity for breeding birds
due to the diversity of habitats including wetland, woodland and hedgerows,
in areas such as Paddington Meadows and The Twiggeries. None of the
features were confirmed as having bat presence during survey and the
majority of features across all sites were considered to have low bat
potential. No signs of otter were found, albeit there remains potential for
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presence. No records or indications of badger or great crested newt were
found.
4.8 Mitigation measures include a combination of:
General good practice, keeping working areas to a minimum and fenced
off to prevent damage to adjacent vegetation;
Reinstatement/planting up of disturbed areas;
Removing trees/shrub suitable for nesting birds outside the bird nesting
period of March to July inclusive;
Keeping riverside vegetation as far as possible;
Keeping trees/linear features suitable for bat commuting/foraging as far
as possible;
Supervision of tree felling by a Natural England licenced bat ecologist
where identified potential for bat roost; and works to be undertaken when
bats are most active, ie between March-May and September-October;
Installing bat boxes to compensate for any loss of trees with bat roost
potential;
Water vole survey to establish population size where works have
potential to disturb habitat and identification of appropriate mitigation
measures if needed;
Temporary measures to prevent water voles using working areas where
no water vole are present;
Changing the defence design/alignment to avoid badger setts and timing
the works to avoid breeding season (incorporated into Phase 1);
Phasing construction, setting back defences; and construction best
practice to reduce impacts / disturbance to fisheries;
A review of detailed construction methods where over-pumping may be
required (potentially Spittle Brook at Cinnamon Brow and Padgate Brook
at confluences with River Mersey and within The Twiggeries) and
identification of mitigation measures if required; and
Keep under review detailed design for phases 2 and 3 to ensure that any
changes to the scheme from the indicative alignments would not have
adverse environmental effects and try to include further beneficial
effects.
4.9 These mitigation measures would control and minimise the potential adverse
effects on ecology, reducing the significance of adverse effect generally to
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negligible. In conclusion, the only remaining adverse effects would be
minor adverse effect on semi-natural broadleaved woodland and plantation;
a minor adverse effect to otter, breeding birds and to bat-roosting potential
and foraging habitat; and a minor to moderate adverse effects on badgers
limited to Phase 1.
4.10 Planned environmental improvements including: the restoration work to
Padgate Brook at the Twiggeries; the removal of a culvert on Padgate Brook
at Orford Road; the placement of bat and bird boxes on the site; and
replacement tree and scrub planting; and wildflower planting will have a
positive impact on biodiversity.
Landscape and Visual Amenity
4.11 Each of the three phases includes residential properties either immediately
adjacent to or overlooking the proposed working areas. The study area also
includes several local commercial and light industrial areas and one school.
Main routes include Kingsway North, Orford Road and Knutsford Road
(A50), and Birchwood Way (A574) to the north east.
4.12 Victoria Park is a significant area of open space close to the town centre.
Other significant open spaces, more natural in character, include the
Twiggeries, Paddington Meadows and Woolston New Cut, all accessible by
public access routes. The Greenway Network is a system of existing and
potential off-road routes for walking and cycling, linking green spaces
throughout the urban area and connecting them to the countryside. The
proposed development affects a diverse range of landscape types, including
natural, semi-natural and ornamental mature tree and shrub cover primarily
along the River Mersey.
4.13 There are no statutory or non-statutory designated landscape near the
proposed development. Key landscape features include the broad river-
valley focusing on the River Mersey and its tributaries with large scale highly
visible industrial development and dense network of transport infrastructure.
4.14 Locally the landscape is generally flat and low-lying with the River Mersey
creating a physical and visual separation between urban areas to the north
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and south. The river and its tributaries are typically lined with trees and
shrubs creating a strong sense of enclosure.
4.15 Sensitive receptors have been identified as residential properties, users of
open space and leisure, road users, and the employees and customers of
local businesses and facilities.
4.16 To reduce the potential effects on the landscape and visual amenity, a
number of mitigation measures have been proposed, including:
Protection of vegetation near the construction works, as set out within
the Tree Removal, Retention and Temporary Tree Protection Plans;
Reinstatement of disturbed grass verges and ground on the wet-side of
the new flood structures;
Replacement tree/shrub planting; and
Improvements and extensions to the riverside walkways and
construction of new steps/ramps to maintain the path network over
structures.
4.17 Even with mitigation measures, there will be significant temporary, adverse
landscape and visual impacts from the vegetation clearance and
construction throughout all three phases. These will persist for the duration
of construction and may result in cumulative effects due to the proximity of
neighbouring sites along the river.
4.18 On completion of the scheme there will still be temporary and permanent
landscape and visual effects from mature vegetation loss and the
introduction of new elements (flood walls and embankments) on the
character of the study area and receptors’ views.
4.19 Knutsford Road will experience the most significant landscape effects due to
loss of tree cover; changes in streetscape character resulting from the flood
defences restricting views of the park and river at Howley Weir; and greater
proportion of hard surfaces in the streetscape. There will be cumulative loss
of vegetative cover across the river at Parkdale Industrial Estate. Once new
planting has matured, the landscape effects will decrease. There may still
be a sense of on-street enclosure generated by the flood defences but this
will have a limited impact on landscape character due to their limited height.
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4.20 15 years after the flood defences have been built, there should be no effects
on landscape character for the majority of residential properties, users of
open space and leisure, road users, and the employees and customers of
local businesses and facilities. However, there may still be minor adverse for
a small number of these receptors, including Knutsford Road. There will be
a minor/moderate beneficial effect on landscape character in several
locations including at the entrance to Victoria Park, The Twiggeries and
open space east of Orford Road.
4.21 In terms of visual effects the most significant change is from vegetation
clearance and flood wall construction at Knutsford Road; and flood
embankment construction west of Kingsway North at The Twiggeries. There
will also be visual effects from vegetation clearance along the river corridor
boundaries. The flood structures are limited in size and nowhere within the
scheme will they permanently block views for pedestrians though ground
floor views for some residents will be reduced.
4.22 15 years after the flood defences are built the majority of visual receptors will
not be affected. There may be minor adverse for a limited number of
residential properties along Knutsford Road and Kingsway North. There will
be a minor/moderate beneficial effect on visual amenity for users of Victoria
Park, The Twiggeries and open space east of Orford Road.
Cultural Heritage
4.23 The river corridor has been used from the prehistoric periods as a route of
communication, a trade route and a fording point across the river (which is
the last crossing point before the sea). There is little evidence of direct
prehistoric settlement in the area. The footprint of the scheme contains
varying levels of archaeological potential both within and on the edges of the
river bank. Features associated with exploitation of the river’s resources
might survive as preserved organic remains amongst the buried river silts.
4.24 There is also a high potential for buried palaeoenvironmental remains both
within the river and the riverbank areas. Former old courses of the River
Mersey are likely to survive underground.
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4.25 The study area includes a number of designated and non designated sites.
The key cultural heritage interest features within or nearby the proposed
scheme are:
Phase 1
Howley Footbridge - Grade II listed bridge that connects the right bank
of the River Mersey with Victoria Park;
Three further listed buildings within the surrounding area: The Old
Warps in Victoria Park (Grade II); No. 484 Knutsford Road (Grade II);
and The Black Bear Pub (Grade II);
Non-designated finds in/around the scheme including: possible Civil
War mound, buried remains from the site of a former 17th century
mansion house at Latchford Grange, site of former Manor Tannery,
ancient ford crossing over the River Mersey, The Manor Lock, and
several find spots along/adjacent to Knutsford Road including former
Latchford Cotton Mill, site of St James’ Church and Graveyard, site of
Latchford Old cotton Mill, former timber yards on Knutsford Road, site
of pin, file and tool works, Latchford Wire and Brush works, site of
timber yard on Wilderspool Causeway, site of Arginstall and Co Wire
Works and site of timber yard on School Street;
Phase 2
Howley Footbridge - Grade II listed bridge that connects the right bank
of the River Mersey with Victoria Park;
Bridge Street Conservation Area which straddles both sides of the
River Mersey near Warrington Bridge;
Four further listed buildings within the surrounding area: The Royal
Oak Pub on Bridge Street; The Old Academy on Bridge Street; bronze
statue of Oliver Cromwell; and cast iron K3 telephone box;
Located within an area identified as Area of Archaeological Potential
which covers the historic core of the town and to the north of the River
Mersey,
Non-designated finds in/around the scheme including: the site of
Mersey Bank Chemical Works No 1; site of Castle India Rubber works;
site of Mersey Flour Mills; four archaeological monuments; and four
further monuments/find spots within the wider area including site of
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cuckstool, site of Whalley’s Yard Tannery and Friary; site of brewery
on Moulder’s Lane and sit eof Phoenix Works;
Phase 3
Orford Hotel - listed building in vicinity of proposed works at Orford
Road;
Non-designated finds in/around the scheme including: line of the Bye
Wash/Feeder at Manor Locks, aqueduct to the Warrington-Latchford
Canal; Woolston New Cut; Woolston Lock; and site of Nos 263 and
265 Padgate Lane which used to be a Wesleyan Methodist Chapel.
4.26 To reduce the potential effects on cultural heritage features and their setting,
a number of mitigation measures have been proposed, including:
Phase 1
South-east corner of Victoria Park - watching brief during early stages
of construction to assess potential for buried archaeology in
association with ancient ford over the River Mersey and appropriate
recording;
St James Church and Graveyard – protective matting across the site
to reduce impact from construction vehicles on potential remains;
heras fencing to be erected to provide protection as necessary; and
watching brief over the digging of pits for replacement tree planting. If
human remains or other archaeological features are discovered during
excavation, these would be left in-situ and the tree-pit relocated;
Phase 2
Howley Footbridge - sensitive design of flood defences during detailed
design and associated landscape reinstatement scheme;
Site of former Mersey Chemical Works No 1 – watching brief over
trench excavations for flood wall;
Site of former Mersey Flour Mills – if reinforced concrete flood wall
construction then watching brief over trench excavation;
Phase 3
Woolston New Cut – watching brief/recording exercise over short
section of flood wall adjacent to the New Cut, the need or otherwise is
to be determined during detailed design;
The Twiggeries – intermittent watching brief during early-stage
construction as precautionary measures;
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Cinnamon Brow – intermittent watching brief during early-stage
construction; and
Orford Road – intermittent watching brief during early-stage
construction.
4.27 Overall the scheme will be beneficial to designated and non-designated built
heritage in the long-term by reducing the risk of flooding throughout the
Mersey corridor in Warrington. The new flood walls will change the historic
settings of some of the designated structures along the course of the
scheme, but these changes will be, at worst, minor adverse. It is also worth
noting that most of these designations have had their settings changed
throughout their existence from general development activity.
4.28 Inserting sheet piles can be destructive to buried archaeological deposits,
although no known archaeological features would be affected by the
scheme.
Land Use and Recreation
4.29 The study area primarily comprises a combination of residential and
industrial/commercial (business and retail) properties, with notable formal
and informal open recreational space most notably Victoria Park and The
Twiggeries, and infrastructure facilities.
4.30 There are no national or regional footpaths or Sustrans cycle paths that pass
through the study area. There are no Public Rights of Way (PRoW) within
Phases 1 or 2; there are 7 PRoW within Phase 3, located across the
Wilkinson Avenue to Kingsway Bridge, Woolston Weir, Orford Road and
Solway Close areas. WBC has also identified potential PRoW across all
three phases of the scheme. Furthermore, the Greenway Network, provides
a borough-wide network of existing and potential off-road routes for walking,
cycling and in some locations horse-riding. There are several local foot and
cycle paths, including Warrington’s Watery Heritage (Phase 1), Howley
Heritage Trail (Phase 2), and the Mersey Way (Phase 2 and Phase 3 in the
Woolston area only).
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4.31 Several recreational clubs use the River Mersey corridor and its tributaries,
most notably Warrington Anglers Association which lease fishing rights on
both banks of the River Mersey between Woolston Weir and Bridgefoot
roundabout, and Warrington Rowing Club whose clubhouse is situated off
Howley Lane with slipway into the River Mersey.
4.32 Future land use is guided by the adopted Warrington Unitary Development
Plan, emerging Core Strategy, the Warrington Regeneration Framework and
other land use and recreation strategies.
4.33 The proposed development and associated landscaping reinstatement
scheme have been designed to minimise the impacts on land use and
recreation, and includes the following mitigation measures:
Working with landowners to agree scheme and reinstatement
proposals;
Reinstatement of PRoW, locally recognised trails and access;
Where necessary for defences to cross existing PRoW and trails,
reinstatement will be designed to be accessible to disabled persons
where feasible;
Reinstatement of the public open recreational space including
improvements to the landscape where feasible;
Re-establishment of access from private gardens to riverside paths
where defence alignment coincides with existing property boundary.
10.4.1 The following further mitigation measures would be undertaken during
detailed design of Phases 2 and 3, and during the construction of all three
phases:
Liaison with landowners/tenants to agree working arrangements,
including programming works to reduce/eliminate adverse impact on
seasonally-critical activities as far as possible;
Minimising the working area and/or moving the working area in stages
as work progresses to reduce the extent and duration of land-take in
any one area;
Providing temporary alternative access to landowners;
Using vacant land (subject to landowner agreement) for the main site
compound (Navigation Street); and
Temporary diversion of PRoW and locally recognised trails.
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4.34 The proposed development would have permanent benefits to the users of
Victoria Park through a revitalised entrance, upgraded road links, increased
parking and the enhancements incorporated into the landscape scheme.
There would also be benefits to the electricity sub-stations at Victoria Park
and Howley Lane, and the gas compound at Orford Road, through increased
flood protection.
4.35 Permanent adverse effects have generally been assessed as either minor or
minor/moderate significance, and include the closure of Weir Lane, albeit
alternative vehicle, disabled and cycle access would be achieved via the
new park entrance; Warrington Rowing Club although this would not
constrain either their existing use or plans for future expansion, and access
to the slipway would be unobstructed; potential to effect to the pumping
station at Cinnamon Brow; Bridge Lane Industrial Estate, primarily affecting
unit 9b; the agricultural grazing land and railway embankment at Orford
Road/The Bennett Recreational Ground; and at Poulton Golf Course at
Cinnamon Brow. These are generally due to the minor land-take required to
construct flood walls/embankment. However, none of these prevent the
continued existing use of the land, albeit they may require some adaptation.
4.36 Temporary effects on land use are generally adverse, from the partial-land
take for the construction working area and disruption to access. These
effects would not prevent the continued use of the land and we will provide
alternative means of access either through diversion or negotiation with the
relevant landowner/tenant.
4.37 There would be no significant permanent effects on recreational routes.
Temporary effects on recreational routes are generally from temporary path
diversions, with the exception of the PRoW / local Sustrans route at Weir
Lane, where local diversions would not be feasible as there are no nearby
alternative bridge crossings of the River Mersey.
4.38 There may be some permanent loss of access to fishing rights over limited
lengths between Wilkinson Avenue and Kingsway Bridge; however, this may
be mitigated during detailed design of Phase 2. There would also be some
temporary disruption to access for fishing during construction.
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4.39 There were no permanent effects identified on future land use aspirations.
4.40 The over-riding benefit of the proposed scheme is the increase to the
standard of protection against flooding for 2,129 residential and 123
industrial/commercial properties within Warrington.
Traffic and Transport
4.41 The River Mersey runs through the borough of Warrington in an east-west
direction, which results in bottlenecks to north-south transport movements at
crossings. Within Warrington there exist only two “crossing” points (the A49
Chester Road / Mersey Street corridor and the A50 Kingsway Bridge). The
M6 Thelwall viaduct (to the east) and the A533 Silver Jubilee Bridge (to the
west) offer the alternative, but more distant, routes.
4.42 At a level local to the scheme the key transport routes that could be as
affected are:
Knutsford Road corridor – an east-west vehicular route to the south of
the River Mersey, providing access to the southern suburbs of
Warrington, including Latchford. The route runs immediately
alongside the river for a stretch between the A49 and Victoria Park,
and it is also located directly along the southern boundary of Victoria
Park;
Manchester Road corridor – an-east-west vehicular route between
Warrington Town Centre and junction 21 of the M6, and serving the
eastern Warrington communities including Woolston. Access from
Manchester Road will be required via local routes for the Bridge Lane
and Weir Lane compounds in Phase 3;
Kingsway North corridor – a north-south corridor offering one of two
opportunities to cross the River Mersey in Warrington;
Orford Road / Birchwood Way corridor – Bordering the western and
northern extents of the Orford Road works, these routes are key local
routes to the east of Warrington Town Centre;
Manchester – Liverpool Railway Line – running in an east-west
direction along the southern fringe of the Orford Road site, the line
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provides the main rail route between the major cities of Manchester
and Liverpool; and
Routes alongside the scheme – in addition to the individual routes
considered above, there exists a number of local routes, public rights
of way and footpaths in the immediate vicinity of the scheme.
4.43 Building the flood defences will create traffic and the surrounding network
will experience some abnormal loads and increased numbers of Heavy
Goods Vehicles and traffic associated with construction related staff.
4.44 To reduce the potential adverse effects on traffic and transport during the
construction stage, the following mitigation measures have been proposed:
Phase 1
ML5 Temporary Haul Route - appropriate traffic management
measures to ensure that the impact on all users, particularly vehicle
and pedestrian users of Knutsford Road, is minimised, to be agreed
with WBC;
ML5 Temporary Closure of Black Brook Park (adopted highway) –
suitable diversion routes to minimise disruption to pedestrians;
ML5/ML6 Temporary Closures of footpaths/disruption to access to
Victoria Park – suitable diversion routes to minimise disruption to
pedestrians;
ML5/ML6 Temporary Traffic Management to accommodate works to
Victoria Park entrance and Knutsford Road Retainer – appropriate
traffic management measures including relocation of bus
stops/pedestrian crossings;
ML6/ML7 Temporary closure of Knutsford Road footway – suitable
diversion routes to minimise disruption to pedestrians and relocation of
bus stops;
ML8 Access for Piling Rig – all vehicle access/egress from site
compound and working areas to be agreed with WBC in advance;
Generation of a Traffic Management Plan to be agreed with WBC in
advance of construction;
Phase 2
MR5 Temporary lane closure between Farrell Street and Navigation
Street – appropriate traffic management measures;
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MR5 Temporary closure of local trail – suitable diversion routes to
minimise disruption to pedestrians;
MR5 Temporary disruption during works over Padgate Brook bridges –
appropriate traffic management;
MR6 Temporary Road Closure of Wharf Street – appropriate traffic
management measures including potential temporary opening of
access to Sutton Street to provide alternative access;
MR6 Temporary closure of local trail - suitable diversion routes to
minimise disruption to pedestrians;
All vehicle access to/from site compound and working areas to be
agreed with WBC in advance. Full consideration of trips generated
during Phase 2 would be identified within the Traffic Management Plan
and appropriate mitigation measures identified;
Phase 3
MR1 Temporary closure of Public Right of Way/local trail - alternative
suitable footway provisions;
MR1 Access to Woolston Weir – Traffic control to be provided where
necessary;
MR2 Access to site by landowners/tenants – liaison with
landowners/tenants to agree access arrangements; various options to
be considered during detailed design;
MR3 Temporary closure of Public Right of Way/local trail - alternative
suitable footway provisions;
MR3/MR4 Temporary closure along Paddington Bank – alternative
traffic management measures including land closure, parking
restrictions and creation of temporary one-way system;
MR4 Temporary closure of Kingsway North footway and relocation of
bus stops – alternative suitable footway provision and relocated bus
stop to appropriate location; and
All vehicle access to/from site compound and working areas to be
agreed with WBC in advance. Full consideration of trips generated
during Phase 3 would be identified within the Traffic Management Plan
and appropriate mitigation measures identified.
4.45 Once the scheme is built, there will be no further deliveries to the site, nor
any fuels or waste removed. Therefore, traffic to the flood defences will only
be vehicles associated with the annual inspection and maintenance of the
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defences. However, there are a number of locations where the proposed
scheme would require some permanent changes to adopted highways and
public rights of way.
4.46 To reduce the potential adverse permanent effects on traffic and transport
the following mitigation measures have been proposed:
Relocated Victoria Park entrance - New 2-way vehicle access ramped
over the defence to Knutsford Road and revised vehicle / pedestrian
access within the park to reinstate connectivity with existing access. A
new vehicle access would be provided between Knutsford Road and
the electricity sub-station;
Relocated Victoria Park entrance conflicts with bus stop and
pedestrian crossing – relocated bus stop and pedestrian crossing;
Closure of Weir Lane – DDA/cycle access provided via new Victoria
Park entrance with pedestrian access provided via steps over flood
wall;
Vehicle access to allotments to be relocated;
Access to Howley Lane electricity sub-station – ramp with flood gate to
provide vehicular access and pedestrian steps to north for emergency
access.
4.47 In conclusion the temporary impacts on traffic from construction would
generally be mitigated to have insignificant effects; however some slight
adverse effects remain due to the nature of the scheme, such as the need
for localised diversion routes, the temporary road closure of Wharf Street
and short-term localised diversion through Sutton Street, temporary closure
of the PRoWs at Woolston Weir and through Orford Road where no suitable
diversion is feasible, and temporary lane closure along Paddington Bank.
4.48 Permanent impacts on traffic and transport are mainly insignificant with
proposed mitigation measures in place. Additionally, there would be some
positive impacts associated with aspects of the scheme including the
widening of Victoria Park entrance and widened riverside foot and cycle
paths.
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Water Environment
4.49 It was determined at scoping stage that the proposed scheme may affect
water quality during construction and may also have permanent effects on
geomorphology/hydromorphology.
Water Framework Directive
4.50 Impacts upon hydromorphology/geomorphology have been considered in a
Water Framework Directive (WFD) compliance assessment to determine
whether the construction of the scheme would adversely affect the water
body, or prevent improvements being made to the water bodies in the future.
4.51 The WFD classifies rivers in terms of how much they have been modified by
humans. This classification includes artificial water bodies created by
humans where no water body previously existed (such as canals) and
heavily modified water bodies (HMWB) whose physical characteristics have
been substantially changed. Four separate water bodies have been
identified within the study area:
Mersey Estuary (Transitional/Estuarine water body) – Identified as a
HMWB with moderate ecological potential and failing current chemical
quality. The WFD objective is to achieve good ecological potential by
2027 and high chemical status by 2027;
River Mersey from Manchester Ship Canal to Howley Weir (including
Padgate Brook) – Identified as a HWMB with moderate ecological
potential and failing current chemical quality. The WFD objective is to
achieve good ecological potential by 2027 and high chemical status by
2027;
Spittle Brook – identified as a HMWB with moderate ecological
potential. The WFD objective is to achieve good ecological potential
by 2027; and
Lower Mersey Basin and North Merseyside Permo-Triassic Sandstone
Aquifers (Groundwater) – identified as poor current chemical quality.
The WFD objective is to attain poor quantitative status by 2015 and
poor chemical status by 2015.
4.52 One of the main reasons for the HMWB designation of the River Mersey is
the existing presence of flood structures at various locations along its length.
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Water Quality
4.53 The River Mersey (from Manchester Ship Canal to Howley Weir) is currently
failing the chemical water quality due to the presence of three priority
hazardous substances. It is also classified as moderate for dissolved oxygen
levels and poor for ammonia and phosphates. Spittle Brook has not been
assessed for chemical quality but is classified as poor for ammonia,
dissolved oxygen and moderate for phosphates.
Groundwater
4.54 The superficial deposits across the central area of Warrington (and
extending along the flanks of the River Mersey) are classified as a
Secondary aquifer with soils classified as having high leaching potential.
4.55 The whole area is considered to form part of the total catchment of a Source
Protection Zone (SPZ); these areas are designated around groundwater
sources used to supply public drinking water. The outer zones of the SPZs
are located north of the M62, approximately 500m from Solway Close.
4.56 To reduce the potential adverse effects on water quality during construction
the contractor will be required to undertake the works in accordance with the
Environment Agency’s Pollution Prevention Guidelines, CIRIA Report 156:
Control of water pollution from construction sites and, where relevant,
legislative and construction best practice with regards to demolition and
construction works. Furthermore, the contractor will be required to ensure
relevant training and staff awareness of site procedures.
4.57 In addition, the following measures are to be adopted where appropriate:
Control of sediment and run-off form working areas;
On-site drainage, interception and collection of run-off.
Disposal of surface water runoff to sewers or tankered to the nearest
Sewage Treatment Work; discharge to watercourses would be
permitted only where approval from the EA has been obtained. The
relevant sections of BS6031: Code of Practice for Earthworks for the
general control of site drainage will be followed;
Control of dewatering activities by use of sheet piles, diaphragm walls
and other groundwater exclusion techniques;
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Disposal of pumped out water to grassed land or into an
infiltration/settlement basin or soakaway as appropriate to the volume
and nature of water;
Dewatering pumping out/return to be at a sufficiently slow rate to
permit water to infiltrate and prevent scour;
Dewatering pumps to be mounted on a tray to catch fuel and drained
regularly;
Spill kits to be on hand in case of emergency with relevant staff
trained in their deployment; and
Works with potential to give rise to degradations in water quality to be
undertaken during dry weather, as far as is possible.
4.58 With the adoption of proposed mitigation measures the risk of pollution
during construction would be controlled and effects would be minor adverse
to negligible.
4.59 The WFD assessment found that the flood defence scheme will not
permanently affect the hydromorphology of the River Mersey, Padgate
Brook or Spittle Brook. Some aspects of the scheme will have beneficial
effects by removing the culvert at Orford Road and restoring the wetland
habitat at The Twiggeries..
Contaminated Land
4.60 The contaminated land assessment comprised a detailed assessment of the
potential risks within Phase 1 to assess the potential ground hazards
including both land stability and contamination, and the associated
influences upon the ground engineering, controlled waters and upon human
health.
4.61 For Phases 2 and 3 a preliminary scoping assessment has been undertaken
to examine the issues which may need to be addressed during detailed
design and to accompany applications for the approval of reserved matters.
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Phase 1
4.62 The current land uses with potential for contamination within Phase 1
include a car rental site with petrol/diesel filling points and associated
underground fuel storage tanks and an automotive repair garage to the west
between the River Mersey and Knutsford Road. To the east, within Victoria
Park, allotments are present which may be associated with the use of
pesticides or spreading of ash. Historical land uses with potential for
contamination along the site include a graveyard and site of the former
Mersey Bank Chemical Works, all of which are located to the west between
the River Mersey and Knutsford Road at the approximate location of the
existing car rental site and automotive repair garage. To the east is the in-
filled Latchford Canal within Victoria Park. No information on the structure of
the canal or what material was used for its infill has been obtained.
Historical plans also indicate that a building located in Victoria Park was
once called “The Old Warps” (now the Spirit restaurant) indicating that land
reclamation may have taken place in the area. Where areas of ground have
been reclaimed, there may be the possibility of Le Blanc waste (galligu)
deposited in the 19th century, which was commonly tipped within Warrington
during this period, particularly in the use of raising ground levels and for
infilling old river channels.
4.63 Accordingly, there is potential for contaminants across Phase 1;
investigations carried out during 2010 identified the presence of asbestos,
arsenic, extractable petroleum hydrocarbons (EPH), concentrations of PAH
and phenol at various locations across Phase 1. No groundwater was
analysed within Phase 1 boreholes and no testing undertaken for pesticides
or herbicides, or Polychlorinated Biphenyl’s (PCBs).
4.64 The likely receptors sensitive to potential contamination are:
Controlled waters;
Humans;
Building fabric (buried concrete); and
The wider environment.
4.65 The potential for aggressive ground conditions is anticipated to vary across
the site; appropriate grade concrete will be assessed and used to mitigate
conditions.
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4.66 Potential effects during construction of Phase 1 prior to mitigation were
identified as:
Humans (residents) – residents inhaling dust borne asbestos and
metals;
Humans (construction workers) – contact with hydrocarbons, metals
and asbestos by contact or inhalation;
Controlled waters (aquifer) – monitoring wells acting as pathways for
contamination migration; and
Controlled waters (River Mersey) – run-off and surface water drainage.
4.67 Potential effects during the operation of Phase 1 were identified as:
Humans (users of public open spaces) – contact, ingestion and/or
inhalation of metals and organics;
Building fabric – aggressive ground conditions attacking the concrete;
and
Controlled waters – direct impact by substances leached from soils.
Phase 2
4.68 Current and historical land uses with potential for contamination include the
electricity sub-station, the Central and Howley tanneries, a transport depot,
paper and saw mills. Ground investigations reported elevated
concentrations of lead and zinc near Howley Quay in made ground, as well
as elevated concentrations of polyaromatic hydrocarbons. Elevated
concentrations of chromium were identified within Phase 2; further sampling
and analysis is required to determine the potential risk to human health.
Elevated concentrations or coliforms were identified in made ground in the
vicinity of the former Howley Tannery, which could post a risk to human
health, particularly construction workers. Furthermore, elevated
concentrations of faecal coliforms were recorded in groundwater obtained
from boreholes at the same location. Leachable concentrations were also
identified within made ground at Howley Quay.
4.69 Likely receptors for the above would be similar to those identified for Phase
1.
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Phase 3
4.70 The stretch of land between Kingsway Bridge and Woolston New Cut Canal
and the Twiggeries did not show significant current and historical land uses
with potential for contamination, consisting primarily of residential, public
open space and allotments. However, elevated concentrations of chromium
were identified at these locations; further sampling and analysis is required
to determinate the potential risk to human health. Ground investigations for
Woolston and Solway Close did not record the presence of any
contaminants likely to give risk to risks to human health. Potential for
pesticides and ash has been identified within the allotments although this
was not identified during ground investigations.
4.71 No analysis of groundwater samples or leachate tested was undertaken at
this time to assess risks to controlled waters. No ground investigation data
is available for Orford Road at this time.
4.72 Likely receptors for the above would be similar to those identified for Phase
1 with the inclusion of Spittle and Padgate Brooks.
4.73 To reduce the potential adverse effects the following mitigation measures
will be employed:
During Construction of Phase 1
Best practice measures in accordance with Health and Safety
Executive guidance, including dust suppression such as dampening
exposed soils and wheel washes for site vehicles as appropriate;
Potential for air monitoring within/outside the construction areas, if
deemed necessary;
Site hygiene measures for construction workers such as appropriate
personal protective equipment and washing facilities;
Locating and decommissioning of acquifer wells in accordance with
standard guidance;
Adherence to best practice guidance including Environment Agency
Pollution Prevention Guidance, such as bunding of oil tanks, use of
drip trays and preparation including emergency spillage action plan;
Design of buried structures to appropriate guidance to reduce risk of
aggressive attack on concrete;
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Management of excavated contaminated soils, ie temporary storage
on covered ground and stockpiled covered to prevent contaminated
run-off, prior to its re-use on site or disposed of off-site in an
appropriately licences facility;
During Operation of Phase 1
Severance of potential pathways by presence of hard standings and
flood structures, and/or use of clean importuned materials;
Buried structures designed/specified in accordance with appropriate
engineering guidance to eliminate risk of aggressive attack by soils on
buried concrete;
Additional site investigations within Victoria Park; and
Remediation/removal of contaminated materials, where deemed
necessary following further validation testing.
4.74 Following the implementation of the above mitigation measures, there will be
no remaining impacts to the ground condition and contamination during the
construction phases. Furthermore, there will be no effects, or moderately
beneficial effects, to the ground condition and contamination during the
operational phases of the flood defences.
4.75 The preliminary appraisal of environmental impacts/constraints for Phases 2
and 3 identified historical uses with potentially contaminative activities;
previous site investigations identified that some exceedences of assessment
criteria in relation to risks to humans, controlled waters and the wider
environment. However, subject to appropriate mitigation such as the
removal of soils/materials containing excessive concentrations of
containments and/or the provision of an inert cover system, the identified
exceedences are not considered to be sufficient to render the site unsuitable
for the proposed flood risk management scheme.
4.76 Further assessment will be undertaken during the detailed design stage for
phases 2 and 3 to consider in detail potential short term ground risks
associated with the re-development of the site, and long term risks
associated with its operation and maintenance. However, it is considered, on
the basis of this assessment, that there are unlikely to be any significant
contamination risks that cannot be resolved by appropriate remediation in
accordance with relevant adopted Government technical guidance.
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Noise and Air Quality
4.77 Impacts on air quality were scoped out of the assessment for the following
reasons:
Although there is the potential for short term impacts upon air quality
as a result of the construction works, from the vehicle movements
required to bring material to the site and from dusty conditions which
may occur during the works, this is considered a minor and short term
impact that can be successfully managed by the adoption of standard
construction practice; and
There would not be any air quality impacts once the flood defence
scheme is complete and in operation.
Phase 1
4.78 Noise will be generated during construction of the flood defences. Within
Phase 1 there are existing residential receptors located approximately 25m
to the south, across Knutsford Road to the proposed works. The works
being undertaken to the rear of commercial properties near Bridgefoot
roundabout are located approximately 40m from the nearest noise sensitive
receptors across Knutsford Road. Latchford Primary School is located
approximately 80m to the south.
Phase 2
4.79 In Phase 2 there are several groups of receptors located at different
distances from works undertaken between Kingsway North and the Howley
Suspension Bridge. From east to west, these are residential properties on
Moorside (approx 140m across the river from Warrington Rowing
club/Padgate Brook and the electricity Sub-station); Salisbury Street
(approximately 375m to the north of works at Farrell and Navigation Street,
including the disused slipway); Birch Court Nursing and Residential Home
(approximately 24m from works); and Riverside Close (within 10m of works
at Howley Suspension Bridge).
4.80 Works undertaken between Howley Suspension Bridge and Bridgefoot
roundabout are within 10m of residential properties on Riverside Close,
extending to approximately 150m when in relation to works at Howley Weir.
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Works are also within approximately 65m of Birch Court Nursing and
Residential home. Works being undertaken on Wharf Street in MR6 are
approximately 110m from Sutton Street to the north.
Phase 3
4.81 During Phase 3, works being undertaken at Woolston Weir would be carried
out within 10m of residential properties on Weir Lane, Edward Gardens and
Timberscombe Gardens. At Bridge Lane Industrial Estate, works would
occur approximately 200m from the closest noise sensitive receptors on
Cliftonville Road to the north, although the Industrial Estate lies between the
works and these receptors.
4.82 At Paddington Bank, the closest residential dwellings would be within 15m of
residential properties on Wilkinson Avenue and Paddington Bank, and 25m
across the A50 Kingsway North in relation to works along Kinsgway North.
4.83 Work undertaken at Twiggeries would be within 15m of residential dwellings
on Bibby Avenue and Peacock Avenue, and 20m of dwellings on the A50
Kingsway North.
4.84 At Orford Road, there would be residential properties within 35m located on
Orford Road and 50m located on Eric Avenue. At Cinnamon Brow/Solway
Close there would be residential dwellings to the west on Solway Close and
to the east on St Andrews Close, all within 10-50m, depending on the
location of the works which are subject to detailed design.
4.85 Liaison with WBC’s Environmental Health Officers indicated that the main
concerns in relation to air and noise quality are likely to be the hours of
operation, ensuring that residents/businesses are well-informed of when and
where works are likely to occur, and providing a consistent means of public
liaison.
4.86 Accordingly, the majority of construction works would be limited to between
8am and 7pm Monday to Friday with no weekend or bank holiday working.
However, it may be necessary to undertake a limited works outside these
times, for example to minimise traffic congestion during works to locally raise
the road at Wharf Street.
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4.87 ‘Best Practicable Means’ would also be employed to minimise construction
impacts, including the following examples,
Keeping local residents and property owners fully informed;
Using local screens or barriers to shield particularly noisy activities;
Use of regularly maintained and appropriately silenced equipment;
Shutting down of equipment when not in use;
Static machines shall be sited as far away as practicable from
inhabited buildings or other noise sensitive locations;
Handling of all materials in a manner which minimises noise;
Moving parts of working platforms and other equipment shall be
lubricated to control noise when being operated;
No vehicles shall wait or queue with their engines running for any
more than 5 minutes;
Switching all audible warning systems to the minimum setting required
by the Health and Safety Executiveor using banksmen; and
Planning the routes and times of deliveries to minimise nuisance to
local communities.
4.88 In Phase 1, receptors located within 25m of works undertaken in Victoria
Park, and also receptors located within 40m of works adjacent to Bridgefoot
roundabout are expected to experience the highest daytime noise levels.
With variation in distance along the length of the works, and the
implementation of mitigation measures as outlined in the mitigation section,
it would be expected that overall construction noise levels may be reduced
at these receptors.
4.89 In Phase 2, receptors on Riverside Close located within 10m, and Birch
Court Nursing and Residential Home within 24m, of works undertaken at
Howley Suspension Bridge are expected to experience the highest daytime
noise levels. With variation in distance along the length of the works, and the
implementation of mitigation measures as outlined in the mitigation section,
it would be expected that overall construction noise levels can be reduced
for the receptors.
4.90 In Phase 3, receptors located within 10m of works undertaken at Woolston
Weir and at Cinnamon Brow/Solway Close, and within 15m of works at
Mersey Warrington Environmental Statement Flood Risk Management Scheme Non-Technical Summary
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Paddington Bank and Orford Road are predicted to experience the highest
daytime noise levels when works are occurring at the closest locations. With
variation in distance along the length of the works, and the implementation
of mitigation measures as outlined in the mitigation section, it would be
expected that overall construction noise levels will be reduced from the
predicted levels for periods of the works.
4.91 With the proposed mitigation and control, measures in place it is considered
that the scheme will comprise only short term and manageable impacts
upon the local noise environment.
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Drawings
Figure Reference Revision Description
IMNW000699/GEN/ENV/001 D Site Location and Site Context Plan
IMNW000699/GEN/ILP/001 E Indicative Landscape Plan Warrington Bridge to Howley Weir Sheet 1 of 8
IMNW000699/GEN/ILP/002 D Indicative Landscape Plan Victoria Park Sheet 2 of 8
IMNW000699/GEN/ILP/003 E Indicative Landscape Plan Victoria Park Entrance Sheet 3 of 8
IMNW000699/GEN/ILP/004 B Indicative Landscape Plan Howley Weir to Kingsway Bridge Sheet 4 of 8
IMNW000699/GEN/ILP/005 C Indicative Landscape Plan Kingsway Bridge to Paddington Meadows Sheet 5 of 8
IMNW000699/GEN/ILP/006 C Indicative Landscape Plan Warrington Bridge to Howley Weir Sheet 6 of 8
IMNW000699/GEN/ILP/007 C Indicative Landscape Plan Bridge Lane and Woolston Weir Sheet 7 of 8
IMNW000699/GEN/ILP/008 C Indicative Landscape Plan Solway Close and Orford Road Sheet 8 of 8
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