Crewe Green Link Road (South) Environmental Statement ......• Guidelines for Landscape and Visual Impact Assessment; 2nd Edition. 2002 – LI/IEMA Spon Press; and • Interim Advice

Highways

Crewe Green Link Road (South) Environmental Statement Volume 3, Technical Appendices Crewe Green Link Road South Crewe, Cheshire

October 2012 B1772401/OD/38

Highways

Page not used

Highways

Originated by Checked by Reviewed by Approved by

ORIGINAL NAME NAME NAME NAME

Ellie Philips Simon Bird Simon Bird Rosie Simon

DATE

18/10/12 INITIALS

EP INITIALS SB INITIALS SB INITIALS

Document Status Final for issue

REVISION NAME NAME NAME NAME

DATE INITIALS INITIALS INITIALS INITIALS

Document Status



Document Status



Document Status

Jacobs U.K. Limited This document has been prepared by a division, subsidiary or affiliate of Jacobs U.K. Limited (“Jacobs”) in its professional capacity as consultants in accordance with the terms and conditions of Jacobs’ contract with the commissioning party (the “Client”). Regard should be had to those terms and conditions when considering and/or placing any reliance on this document. No part of this document may be copied or reproduced by any means without prior written permission from Jacobs. If you have received this document in error, please destroy all copies in your possession or control and notify Jacobs. Any advice, opinions, or recommendations within this document (a) should be read and relied upon only in the context of the document as a whole; (b) do not, in any way, purport to include any manner of legal advice or opinion; (c) are based upon the information made available to Jacobs at the date of this document and on current UK standards, codes, technology and construction practices as at the date of this document. It should be noted and it is expressly stated that no independent verification of any of the documents or information supplied to Jacobs has been made. No liability is accepted by Jacobs for any use of this document, other than for the purposes for which it was originally prepared and provided. Following final delivery of this document to the Client, Jacobs will have no further obligations or duty to advise the Client on any matters, including development affecting the information or advice provided in this document. This document has been prepared for the exclusive use of the Client and unless otherwise agreed in writing by Jacobs, no other party may use, make use of or rely on the contents of this document. Should the Client wish to release this document to a third party, Jacobs may, at its discretion, agree to such release provided that (a) Jacobs’ written agreement is obtained prior to such release; and (b) by release of the document to the third party, that third party does not acquire any rights, contractual or otherwise, whatsoever against Jacobs and Jacobs, accordingly, assume no duties, liabilities or obligations to that third party; and (c) Jacobs accepts no responsibility for any loss or damage incurred by the Client or for any conflict of Jacobs’ interests arising out of the Client's release of this document to the third party.

Highways

Page not used

Highways

Contents

Appendix A - Consultation 1

Appendix A.1 - CEC Scoping Opinion 1

Appendix A.2 - Consultation Response 1

Appendix B - Landscape and Visual Impacts 1

Appendix B.1 - Landscape Methodology 1

Appendix B.2 - Arboricultural Implication Assessment 1

Appendix B.3 - Visual Effects Schedule 1

Appendix B.4 - Environmental Masterplan 1

Appendix B.5 - Tree Constraints plan 1

Appendix C - Ecology 1

Appendix C.1 - Legislation and Policy Guidance 1

Appendix C.2 - Ecological Designated Sites 1

Appendix C.3 - Phase 1 habitat survey figure 1

Appendix C.4 - Phase 1 habitat survey target notes 1

Appendix C.5 - White-clawed crayfish survey report 1

Appendix C.6 - Reptile survey report 1

Appendix C.7 - Great Crested Newts survey report 1

Appendix C.8 - Confidential Badger survey report (available upon request) 1

Appendix C.9 - Confidential barn owl survey report (available upon request) 1

Appendix C.10 - Bat survey report 1

Appendix C.11 - Otter and water vole survey report 1

Appendix C.12 - Kingfisher survey report 1

Appendix C.13 - GCN outline mitigation strategy 1

Appendix C.14 - Middlemarch Basford East, Crewe GCN survey 2012 1

Appendix C.15 - Middlemarch Basford East, Crewe Bat survey 2012 1

Highways

Appendix C.16 - Middlemarch Basford East, Crewe Breeding Birds survey 2012 1

Appendix C.17 - Middlemarch Basford East, Crewe Aquatic Macrophyte and invertebrate survey 2012 1

Appendix C.18 - Ecological impacts characterisation table 1

Appendix D - Archaeology 1

Appendix D.1 - Cultural Heritage Assessment 1

Appendix D.2 - Geophysical Survey Results 1

Appendix D.3 - Heritage Gazette 1

Appendix E - Air Quality 1

Appendix F - Noise and Vibration 1

Appendix G - Soils, Geology and hydrogeology 1

Appendix G.1 - Geo-environmental Desk Study Report 1

Appendix H - The Water Environment 1

Appendix H.1 - HAWRAT assessment Methodology 1

Appendix H.2 - WFD Objectives 1

Appendix H.3 - Addendum to FRA 1

Appendix H.4 - Summary of the results from the HAWRAT and spillage risk assessment 1

Highways

Appendix A - Consultation

Highways

Page not us

Highways

Appendix A.1 - CEC Scoping Opinion

Highways

Page not used

Highways

Appendix A.2 - Consultation Response

Highways

Page not used

Highways

Appendix B - Landscape and Visual Impacts

Highways

Page not used

Highways

Appendix B.1 - Landscape Methodology

Highways

Page not used

1

Highways

Methodology including Significance

The following methodology has been used for the assessment and is derived in accordance to the following guidance documents:

• Guidelines for Landscape and Visual Impact Assessment; 2nd Edition. 2002 – LI/IEMA Spon Press; and

• Interim Advice Note (IAN) 135/10 Landscape and Visual Effects Assessment (which replaces Design Manual for Road and Bridges (DMRB); Volume 11; Section 3; Part 5 – Landscape Effects) – Highways Agency, November 2010

The LI/IEA Guidance states that “… landscape impacts and visual impacts are separate, but related. Landscape impacts are changes in the fabric, character and quality of the landscape. Visual impacts relate solely to changes in available views of the landscape, and the effects of those changes on people. Landscape and visual impacts do not necessarily coincide.”

Existing, Baseline and future conditions

The landscape and visual baseline information has been described for the existing year and has considered any changes that might occur in this baseline prior to the construction year. The assessment has then considered the effects of proposals in three scenarios:

• During construction considering construction activities, compounds and traffic;

• On a winters day in the opening year before mitigation planting has begun to take effect; and

• A summers day in the fifteenth year after opening when mitigation planting can be assumed to be substantially effective.

Landscape Character Assessment

The existing/baseline landscape character has been identified in terms of regional and local context. The survey area has been divided into landscape character areas, in this case utilising the areas as defined in the original ES, which can then be assessed in terms of quality and value. This has in turn determined the sensitivity of the landscape (see Table 1). This sensitivity rating has been assessed against the proposed magnitude of change (See Table 2) in order to give an overall significance of effect (See Table 3).

Landscape quality is defined as follows:

“Landscape quality (or condition) is based on judgements about the physical state of the landscape, and about its intactness, from visual, functional, and ecological perspectives. It also reflects the state of repair of individual features and elements which make up the character in any one place.”

Landscape value is defined as follows:

2

Highways

“The relative importance attached to a landscape (often as a basis for designation or recognition), which expresses national or local consensus, because of its quality, special qualities including perceptual aspects such as scenic beauty, tranquillity or wildness, cultural associations or other conservations issues.”

Visual Effects Assessment

This part of the assessment considers physical changes in views for receptors of the proposed scheme. Changes in visual impact would arise as a result of the loss of existing components e.g. the loss of existing vegetation, the restriction of long distance views, changes to landscape character, and the introduction of new features such as earthworks, structures and lighting, as well as traffic using the new road.

The Zone of Theoretical Visibility (ZTV) is the area from which the proposed scheme or part of the scheme may be visible. The potential ZTV will be noted during the site visits and a resulting Visual Envelope Map (VEM) will be produced. The VEM reflects the visibility of the site based upon the topography of the surrounding area and known elements such as buildings and the existing vegetation, where noted in the visual assessment, which provide all year screening. It should be noted that there will be areas within the VEM which do not have views of the scheme (due to the screening effects of vegetation, structures, local topographical formations, etc.), but it is an approximate guide used to assist in identifying key visual receptors.

As with landscape character, visual receptors has been assessed by giving a sensitivity rating (See Table 1) and assessing against the proposed magnitude of change (See Table 2). This will result in a significance of effect (See Table 3).

Sensitivity of Landscape and Visual Receptors

The Landscape Institute’s Guidelines for Landscape and Visual Impact Assessment defines landscape sensitivity in the Glossary as “The extent to which a landscape can accept change of a particular type and scale without unacceptable adverse effects on its character.” Sensitivity reflects the vulnerability of the landscape character/quality to accept or accommodate the proposed change (see magnitude of change).

In some instances a landscape with important elements may be of a lower sensitivity as a result of its potential tolerance to change e.g. a variable landform or high levels of tree cover. Conversely, a landscape with few features of interest may be of a higher sensitivity because it is vulnerable to the introduction of a road and traffic e.g. a flat landscape with an open character where screen planting would be inappropriate. Although the criteria have been established in Table 1, the assessment has relied upon professional judgement and subjective opinion based on professional experience.

The sensitivity of visual receptors not only depends on the type of receptor, but also on the context and perceptions of the viewer; the activity or occupation that brings them into contact with the view and the nature of the view, whether full or glimpsed, near or distant. In assessing the effects of the development proposals, the HA Interim Advice Note 135 (IAN 135/10) recommend criteria for sensitivity of the landscape or visual receptor which have been developed in accordance with the GLVIA and summarised in Table 1.

Table 1: Landscape and Visual Sensitivity Criteria Descriptors

3

Highways

SENSITIVITY Landscape Visual

HIGH

Landscapes which by nature of their character would be unable to accommodate change of the type proposed. Typically these would be:

� Of high quality with distinctive elements and features making a positive contribution to character and sense of place.

� Likely to be designated, but the aspects which underpin such value may also be present outside designated areas, especially at the local scale.

� Areas of special recognised value through use, perception or historic and cultural associations.

� Likely to contain features and elements that are rare and could not be replaced.

� Residential properties

� Users of Public Rights of Way or other recreational trails (e.g. National Trails, footpaths, bridleways etc.).

� Users of recreational facilities where the purpose of that recreation is enjoyment of the countryside (e.g. Country Parks, National Trust or other access land etc.).

MODERATE

Landscapes which by nature of their character would be able to partly accommodate change of the type proposed. Typically these would be:

� Comprised of commonplace elements and features creating generally unremarkable character but with some sense of place.

� Locally designated, or their value may be expressed through non-statutory local publications.

� Containing some features of value through use, perception or historic and cultural associations.

� Likely to contain some features and elements that could not be replaced

� Outdoor workers

� Users of scenic roads, railways or waterways or users of designated tourist routes.

� Schools and other institutional buildings, and their outdoor areas.

LOW

Landscapes which by nature of their character would be able to accommodate change of the type proposed. Typically these would be:

� Comprised of some features and elements that are discordant, derelict or in decline, resulting in indistinct character with little or no sense of place.

� Not designated.

� Containing few, if any, features of value through use, perception or historic and cultural associations.

� Likely to contain few, if any, features and elements that could not be replaced.

� Indoor workers

� Users of main roads (e.g. trunk roads) or passengers in public transport on main arterial routes.

� Users of recreational facilities where the purpose of the recreation is not related to the view (e.g. sports facilities).

Magnitude of Impact

The magnitude of impact is the degree of change that would occur during the construction and operation of the proposed scheme. Magnitude is determined by the perceived contrast or integration with the existing scenic features and aesthetic character of the view in terms of its form, line, colour, texture and scale. It also considers the duration of the impacts.

Duration is categorised as:

Short term - Up to 1 year or during construction

Short/Medium term - 1 to 5 years when new planting will not be effective

Medium/Long term - 5 to 15 years when planting will be effective mitigation

Long term - Over 15 years

4

Highways

The criteria for the magnitude of impact are described in Table 2. Landscape magnitude is described in terms of adverse and beneficial impact whereas visual magnitude is described as the degree of change.

Table 2: Magnitude of Impact Descriptors

MAGNITUDE Landscape Visual

MAJOR

Total loss or large scale damage to existing character or distinctive features and elements, and/or the addition of new but uncharacteristic conspicuous features and elements. Large scale improvement of character by the restoration of features and elements, and/or the removal of uncharacteristic and conspicuous features and elements, or by the addition of new distinctive features.

The project, or a part of it, would become the dominant feature or focal point of the view.

MODERATE

Partial loss or noticeable damage to existing character or distinctive features and elements, and/or the addition of new but uncharacteristic noticeable features and elements. Partial or noticeable improvement of character by the restoration of existing features and elements, and/or the removal of uncharacteristic and noticeable features and elements, or by the addition of new characteristic features.

The project, or a part of it, would form a noticeable feature or element of the view which is readily apparent to the receptor.

MINOR

Slight loss or damage to existing character or features and elements, and/or the addition of new but uncharacteristic features and elements. Slight improvement of character by the restoration of existing features and elements, and/or the removal of uncharacteristic features and elements, or by the addition of new characteristic elements.

The project, or a part of it, would be perceptible but not alter the overall balance of features and elements that comprise the existing view.

NEGLIGIBLE

Barely noticeable loss or damage to existing character or features and elements, and/or the addition of new but uncharacteristic features and elements. Barely noticeable improvement of character by the restoration of existing features and elements, and/or the removal of uncharacteristic features and elements, or by the addition of new characteristic elements.

Only a very small part of the project would be discernable, or it is at such a distance that it would form a barely noticeable feature or element of the view.

NO CHANGE

No noticeable loss, damage or alteration to character or features or elements.

No part of the project, or work or activity associated with it, is discernible.

Assessment of Significance of Landscape and Visual Effects

The assessment of significance of landscape and visual effects has been assessed using the same criteria as set out in Table 4 and the typical descriptors of these categories in show in Table 3. These levels of significance can either be beneficial or adverse. The matrix is used as a guide but it relies upon the common sense, experience and reasoned judgement, supported by substantiated evidence. For each specific case the score is as much based on a reasoned professional judgement of the assessor. For example, in some circumstance where the receptor is considered to be high sensitivity and the magnitude considered to be moderate then justification for giving a moderate or large significance will be required.

5

Highways

Table 3: Typical Descriptors of Significance of Effect Categories

CATEGORY Landscape Visual

VERY LARGE BENEFICIAL

EFFECT

The project would greatly enhance the character (including quality and value) of the landscape; create an iconic high quality feature and/or series of elements; enable a sense of place to be created or greatly enhanced.

The project would create an iconic new feature that would greatly enhance the view.

LARGE BENEFICIAL

EFFECT

The project would enhance the character (including quality and value) of the landscape; enable the restoration of characteristic features and elements lost as a result of changes from inappropriate management or development; enable a sense of place to be enhanced.

The project would lead to a major improvement in a view from a highly sensitive receptor.

MODERATE BENEFICIAL

EFFECT

The project would improve the character (including quality and value) of the landscape; enable the restoration of characteristic features and elements partially lost or diminished as a result of changes from inappropriate management or development; enable a sense of place to be restored.

The proposals would cause obvious improvement to a view from a moderately sensitive receptor, or perceptible improvement to a view from a more sensitive receptor.

SLIGHT BENEFICIAL

EFFECT

The project would complement the character (including quality and value) of the landscape; maintain or enhance characteristic features and elements; enable some sense of place to be restored.

The project would cause limited improvement to a view from a receptor of medium sensitivity, or would cause greater improvement to a view from a receptor of low sensitivity.

NEUTRAL EFFECT

The project would maintain the character (including quality and value) of the landscape; blend in with characteristic features and elements; enable a sense of place to be retained.

No perceptible change in the view.

SLIGHT ADVERSE EFFECT

The project would not quite fit the character (including quality and value) of the landscape; be at variance with characteristic features and elements; detract from a sense of place.

The project would cause limited deterioration to a view from a receptor of medium sensitivity or cause greater deterioration to a view from a receptor of low sensitivity.

MODERATE ADVERSE EFFECT

The project would conflict with the character (including quality and value) of the landscape; have an adverse impact on characteristic features or elements; diminish a sense of place.

The project would cause obvious deterioration to a view from a moderately sensitive receptor, perceptible damage to a view from a more sensitive receptor.

LARGE ADVERSE EFFECT

The project would be at considerable variance with the character (including quality and value) of the landscape; degrade or diminish the integrity of a range of characteristic features and elements; damage a sense of place.

The project would cause major deterioration to a view from a highly sensitive receptor, and would constitute a major discordant element in the view.

VERY LARGE ADVERSE EFFECT

The project would be at complete variance with the character (including quality and value) of the landscape; cause the integrity of characteristic features, elements and sense of place to be lost.

The project would cause the loss of views from a highly sensitive receptor, and would constitute a dominant discordant feature in the view.

Mitigation Measures

The assessment and proposals are part of an iterative process which leads to the identification of potential mitigation measures. The mitigation proposals are based not solely on the landscape and visual assessment but also take account of the

6

Highways

concerns and recommendations made by statutory bodies as well as other disciplines.

Early identification allows responsive design to eliminate or reduce adverse effects and therefore proposals should first prevent effects to receptors and replace lost landscape value. If that is not achievable, then proposals should reduce or offset the construction or operation of a development. They should create landscape opportunities to enhance the landscape condition and maximise the use of creative design and possibilities for advance planting. They should integrate with the surrounding landscape character, retain existing vegetation, compensate for the loss of trees, shrubs and hedges where retention is not feasible, reflect local species and provide additional benefit where possible.

Table 4 – Significance of Effect Matrix

No Change Negligible Minor Moderate Major

L

AN

DS

CA

PE

SE

NS

ITIV

ITY

Hig

h

Neutral

Slight

Slight/ Moderate

Moderate/ Large

Large/Very Large

Mo

dera

te

Neutral

Neutral/ Slight

Slight

Moderate

Moderate/ Large

Lo

w

Neutral

Neutral/ Slight

Neutral/ Slight

Slight

Slight/ Moderate

Highways

Appendix B.2 - Arboricultural Implication Assessment

Highways

Page not used

Highways

Appendix B.3 - Visual Effects Schedule

Highways

Page not used

Highways

Appendix B.4 - Environmental Masterplan

Highways

Page not used

Highways

Appendix B.5 - Tree Constraints plan

Highways

Page not used

Highways

Appendix C - Ecology

Highways

Page not used

Highways

Appendix C.1 - Legislation and Policy Guidance

Highways

Page not used

Highways

Appendix C.2 - Ecological Designated Sites

Highways

Page not used

Highways

Appendix C.3 - Phase 1 habitat survey figure

Highways

Page not used

Highways

Appendix C.4 - Phase 1 habitat survey target notes

Highways

Page not used

Highways

Appendix C.5 - White-clawed crayfish survey report

Highways

Page not used

Highways

Appendix C.6 - Reptile survey report

Highways

Page not used

Highways

Appendix C.7 - Great Crested Newts survey report

Highways

Page not used

Highways

Appendix C.8 - Confidential Badger survey report (available upon request)

Highways

Page not used

Highways

Appendix C.9 - Confidential barn owl survey report (available upon request)

Highways

Page not used

Highways

Appendix C.10 - Bat survey report

Highways

Page not used

Highways

Appendix C.11 - Otter and water vole survey report

Highways

Page not used

Highways

Appendix C.12 - Kingfisher survey report

Highways

Page not used

Highways

Appendix C.13 - GCN outline mitigation strategy

Highways

Page not used

Highways

Appendix C.14 - Middlemarch Basford East, Crewe GCN survey 2012

Highways

Page not used

Highways

Appendix C.15 - Middlemarch Basford East, Crewe Bat survey 2012

Highways

Page not used

Highways

Appendix C.16 - Middlemarch Basford East, Crewe Breeding Birds survey 2012

Highways

Page not used

Highways

Appendix C.17 - Middlemarch Basford East, Crewe Aquatic Macrophyte and invertebrate survey 2012

Highways

Page not used

Highways

Appendix C.18 - Ecological impacts characterisation table

Highways

Page not used

Highways

Appendix D - Archaeology

Highways

Page not used

Highways

Appendix D.1 - Cultural Heritage Assessment

Highways

Page not used

Highways

Appendix D.2 - Geophysical Survey Results

Highways

Page not used

Highways

Appendix D.3 - Heritage Gazette

Highways

Page not used

Highways

Appendix E - Air Quality

Highways

Page not used

1

Highways

Table E.1: AADT flows for the year of opening

Road Detail Year of opening Do Minimum

Year of opening Do Something

AADT flow

Speed km/hr

HGV %

AADT flow

Speed km/hr

HGV %

A500 (EB) West of the proposed scheme

10544 89 5 13105 89 5

A500 (WB) 10056 86 5 12203 85 5

A500 (EB) East of the proposed scheme

10544 86 5 8717 86 6

A500 (WB) 10056 89 6 8385 87 6

Proposed Road (NB) - - - 3817 50 2

Proposed Road (SB) - - - 4387 59 3

Main Road (NB) 4183 45 2 3815 44 2

Main Road (SB) 5036 59 1 4524 60 1

Weston Road (EB)

Between University Way and Main Road

10469 58 5 9638 59 6

Weston Road (WB)

10185 58 6 9972 57 6

Nantwich Road (A534) (EB)

Between the A5020 and Gresty Road

10456 18 5 9690 19 5

Nantwich Road (A534) (WB)

12575 9 5 12076 10 5

Univ. Way (NB)

Near the roundabout with Western Road

5449 39 4 6835 29 4

Univ. Way (SB)

6247 56 4 7851 56 3

Nantwich Road (A534 (EB)

Within the AQMA

5617 26 5 5502 26 5

Nantwich Road (A534 (WB)

5135 30 5 5179 28 5

Crewe Road (EB)

Between A532 roundabout and Narrow Lane

5812 50 3 6189 50 3

Crewe Road (WB)

6251 50 2 6475 50 2

Gresty Road (EB)

Between Claughton Avenue

8097 34 3 7197 34 3

Gresty Road (WB)

7726 34 3 6880 35 3

Claugton Avenue (off Gresty Road) 2 way data

544 19 1 546 20 1

Davenport Avenue (EB) 1893 19 4 2197 20 3

Davenport Avenue (WB) 1750 29 4 1816 29 4

Laura Street (EB) 935 7 3 1004 8 3

Laura Street (WB) 1523 19 1 1446 19 1

1

Highways

Page not used

Highways

Appendix F - Noise and Vibration

Highways

Page not used

1

Highways

Acoustic Definitions

A sound wave travelling through the air is a regular disturbance in ambient atmospheric pressure. These pressure fluctuations, when of frequencies within the audible range, are detected by the human ear which passes nerve responses to the brain, producing the sensation of hearing. Noise has been defined in a variety of ways and is very much dependant on factors such as the listener’s attitude to the source of the sound and their environment, but is essentially any sound that is unwanted by the recipient.

It is impossible to measure the degree of nuisance caused by noise directly, as this is essentially a subjective response of the listener, but it is possible to measure the “loudness” of that noise. Loudness is related to both the sound pressure (the magnitude of the maximum excursion of the pressure wave around the ambient atmospheric pressure) and the frequency, both of which can be measured.

The human ear is sensitive to a wide range of sound levels; the sound pressure level of the threshold of pain is over a million times that of the quietest audible sound. In order to reduce the relative magnitude of the numbers involved, a logarithmic scale of decibels (dB) based on a reference level of the lowest audible sound is used.

Also, the response of the human ear is not constant over all frequencies. It is therefore usual to weight the measured frequency to approximate human response. This is achieved by using filters to vary the contribution of different frequencies to the measured level. The “A” weighting network is the most commonly used and has been shown to correlate closely to the non-linear and subjective response of humans to sound. The use of this weighting is denoted by a capital A in the unit abbreviation (i.e. LAmax, LAeq, LA90 etc.) or a capital A in brackets after a dB level (i.e. 3 dB(A)).

Sound Pressure Level: The sound pressure level (LP or SPL) is the instantaneous acoustic pressure and is measured in decibels (dB). Since the ear is sensitive to variations in pressure, rather than source power or intensity, the measurement of this parameter gives an indication of the impact on people. The SPL is defined as:

=

2

2

1010

refp

pSPL log

or

=

refp

pSPL

1020 log

where:

p is the rms pressure of the sound in question (in pascals)

pref is the reference sound pressure, defined as the limit of human audibility (2 x 10-5 Pa)

Leq: The Leq is defined as the equivalent continuous sound level and is the most widely used parameter for assessing environmental noise. Since this descriptor is a type of average level, it must by definition have an associated time period over which the measurement is referring to. This is often included in the abbreviation in

2

Highways

the form Leq, T, where T is the time period (i.e. LAeq, 5 min). The formula for calculating the Leq is:

−= ∫ dt

p

p

ttL

t

tref

eq .log2

12

2

12

10

110

In practice, since most modern sound level meters are digital and hence take periodic samples of the sound pressure level, the Leq will be the logarithmic average of all the SPL samples taken in the measurement period.

Lmax: The Lmax is defined as the maximum rms level recorded during a measurement period.

L10: The L10 refers to the level exceeded for 10% of the measurement period and is widely considered as the standard index to describe traffic noise.

L90: The L90 refers to the level exceeded for 90% of the measurement period and is widely considered to represent background noise, or the underlying noise in an area between noisy events (such as cars passing etc.).

Façade: The term “façade” refers to noise levels that have been measured or predicted 1 metre in front of the most exposed window or door in a façade.

Free-Field: The term “free-field” refers to noise levels that have been measured or predicted in the absence of any influence of reflections from nearby surfaces. In practice, a measurement is considered to be free-field if it was taken at a distance of over 3.5 m from any reflecting surfaces.

Lnight: The Lnight is a façade noise index derived from the LA10,18h index using TRL conversion method.

Lnight,outside: The Lnight,outside is defined as the free-field A-weighted long-term average sound level of the 8-hour night-time period determined over all nights of a year outside a property.

3

Highways

Noise Monitoring

The wind direction at each of the locations varied from day to day. On 12th February 2010, there was an easterly breeze, on 16th February 2010, there was a south westerly breeze. On the 19th February there was a southerly breeze and on 22nd February 2010, a north-easterly breeze.

Location 1 - between 1 and 2 Fourways

The sound level meter was located on Fourways, off Cemetery Road approximately 350 metres south-west of the proposed link road and approximately 12 metres from Cemetery Road. The sound level meter was positioned 1.3 metres above the ground in free-field conditions. The monitoring equipment was calibrated before and after the monitoring period using an acoustic calibrator, which has itself been calibrated against a reference set traceable to National and International Standards. There was no shift in the observed calibration level. During the measurement periods the main sources of noise were road traffic noise from Cemetery Road, background road traffic noise from the nearby A500 and birdsong.

Table F.1: Noise monitoring between 1 and 2 Fourways

Date

Start

Time

15 Minute Sound Pressure Level (dB)

LAeq

LA10

LA90

LAFmax

Daytime

12/02/2010 12:14 53.9 53.5 48.0 70.0

12/02/2010 13:56 55.3 55.0 48.5 72.2

16/02/2012 13:35 50.7 47.5 40.0 70.3

22/02/2010 10:32 54.8 53.0 47.5 75.4

22/02/2010 10:47 52.1 51.5 47.0 71.5

Night-time

16/02/2012 20:53 52.3 50.0 41.0 75.0

16/02/2012 21:13 48.8 49.0 41.0 68.8

Location 2 - Newstead

The sound level meter was located in the front garden of Newstead, a bungalow on Whites Lane, approximately 225 metres south of the propose link roads and approximately 7 metres from Whites Lane. The sound level meter was positioned 1.3 metres above the ground in free-field conditions. The monitoring equipment was calibrated before and after the monitoring period using an acoustic calibrator, which has itself been calibrated against a reference set traceable to National and International Standards. There was no shift in the observed calibration level.

During the measurement periods the main sources of noise were road traffic noise from Whites Lane, background road traffic noise from the A500 and birdsong.

Table F.2: Newstead

Date

Start

Time


LAeq

LA10

LA90

LAFmax

Daytime

22/02/2010 11:05 54.3 51.5 46.5 76.6

4

Highways

22/02/2010 11:20 55.3 55.5 47.0 78.9

12/02/2010 12:33 56.9 53.5 48.0 79.5

12/02/2010 14:14 60.0 59.0 47.5 78.5

16/02/2012 14:16 59.1 59.0 45.0 80.2

Night-time

16/02/2012 21:35 49.4 48.0 43.0 69.3

16/02/2012 22:07 52.9 49.5 44.0 76.2

Location 3 - Crotia Mill Farm

The sound level meter was located on Mill Lane, leading up to Crotia Mill Farm, approximately 300 metres north-west of the proposed link road. The sound level meter was positioned 1.3 metres above the ground in free-field conditions. The monitoring equipment was calibrated before and after the monitoring period using an acoustic calibrator, which has itself been calibrated against a reference set traceable to National and International Standards. There was no shift in the observed calibration level.

During the measurement periods the main sources of noise were road traffic noise from the A500, birdsong, wind in the surrounding trees and occasional train ‘horn’ from the Crewe Line.

Table F.3: Crotia Mill Farm

Date

Start

Time


LAeq

LA10

LA90

LAFmax

Daytime

22/02/2010 09:53 54.3 51.5 46.5 66.8 22/02/2010 10:08 55.0 57.0 52.0 65.0

12/02/2010 13:00 53.9 56.0 50.5 66.7

16/02/2012 13:55 56.5 59.0 52.0 63.4

12/02/2010 14:34 51.1 53.0 48.0 64.1

Night-time

16/02/2012 20:18 51.9 54.5 47.5 62.3

16/02/2012 20:33 51.0 54.0 46.0 61.4

19/02/2012 23:00 52.6 55.0 48.0 67.5

19/02/2012 23:15 52.9 55.5 48.0 61.8

19/02/2012 23:30 52.8 56.0 47.5 68.3

19/02/2012 23:45 52.4 55.5 47.0 65.6

Location 4 - Dairy House

The sound level meter was located in the front garden of Dairy House on Weston Lane approximately 720 metres west of the proposed link road and approximately 20 metres from Weston Lane. The sound level meter was positioned 1.3 metres above the ground in free-field conditions. The monitoring equipment was calibrated before and after the monitoring period using an acoustic calibrator, which has itself been calibrated against a reference set traceable to National and International Standards. There was no shift in the observed calibration level.

During the measurement periods the main sources of noise were road traffic noise on the A500, local traffic on Weston Lane, birdsong and the occasional train ‘horn’ from the Crewe Line to the west.

5

Highways

Table F.4: Dairy House

Date

Start

Time


LAeq

LA10

LA90

LAFmax

Daytime

22/02/2010 09:17 55.2 57.5 51.0 66.1 22/02/2010 09:32 55.4 58.0 50.0 77.1

12/02/2010 13:27 52.7 56.0 47.0 63.0

12/02/2010 14:54 53.0 55.5 48.0 70.6

Night-time

16/02/2012 19:42 50.6 53.0 43.5 64.5

16/02/2012 19:57 50.6 53.0 43.5 64.5

6

Highways

Page not used

7

Highways

Construction Plant Information

Table F.5: Construction Plant Information

Scenario Activity Construction Phase

Plant No. of Plant

Noise level

dB(A) at 10 m

Plant height

(m) %

On time

BS 5228 Reference

1 – Normal working hours

Excavate Road (Chainage 300 – 600) and Excavate (Chainage 600 – end)

27 and 46

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

25t Dumper (mobile)

3 per hr 109* 1.8 30 C.2.33

Create Pond 82

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

25t Dumper (mobile)

3 per hr 109* 1.8 30 C.2.33

Top soil strip 26

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

25t Dumper (mobile)

1 109* 1.8 30 C.2.33

Culvert 88 25t Excavator 1 77 1.5 50 C.2.19

Backhoe loader 1 68 1.8 50 C.2.8

8

Highways

Water pump 1 62 0.5 100 C.2.46

10t Dumper (idling) 1 63 1.8 25 C.4.5


Top soil to pond 83

25t Dumper (idling) 1 74 1.8 100 C.2.32

25t Excavator 1 77 1.5 90 C.2.19

30t Dump truck (mobile)

3 per hour

109* 1.8 50 C.2.33

Borrow pit creation

84

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

30t Dumper (mobile)

4 per hour

109* 1.8 40 C.2.33

Excavate pond 85

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

30t Dumper (mobile)

3 per hour

109* 1.8 30 C.2.33

Culvert (Chainage 930)

89

25t Excavator 1 77 1.5 90 C.2.19


Water pump 1 62 0.5 100 C.2.46

10t Dumper (idling) 1 63 1.8 25 C.4.5

Top soil strip (east and west spur)

65

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C2.12

25t Dumper (idling) 1 74 1.8 100 C.2.32

25t Dumper (mobile)

3 per hour

109* 1.8 30 C.2.33

9

Highways

3 – Normal working hours Various storm

drainage 90 - 186

25t Excavator 1 77 1.5 90 C.2.19


Water pump 1 62 0.5 100 C.2.46

10t Dumper (idling) 1 63 1.8 25 C.4.5

Piling (Chainage 70 - 156)

189

Giken power pack 1 68 1.8 50 C.3.10

55t Tracked crane 1 80 2.0 90 C.3.29

Piling (Chainage 187 - 290)

190


55t Tracked crane 1 80 2.0 90 C.3.29


Surfacing (Chainage 600 to 1000)

50

Paver 1 77 2.0 90 C.5.31

Vibratory roller 1 84 1.0 90 C.5.24

Road lorry (idling) 1 63 1.8 50 C.4.5

Road lorry (mobile) 3 per hour

108* 1.8 30 C.4.20

Various storm drainage

90 - 186

25t Excavator 1 77 1.5 90 C.2.19


Water pump 1 62 0.5 100 C.2.46

10t Dumper (idling) 1 63 1.8 25 C.4.5

Bridge deck – Excavate and prepare

228 25t Excavator 1 77 1.5 90 C.2.19


Surfacing (Chainage 300 to 600)

31

Paver 1 77 2.0 90 C.5.31



Footpath 52 Backhoe loader 1 68 1.8 50 C.2.8

10

Highways

preparation and surfacing (Chainage 600 to end)

3t Vibratory roller 1 67 1.0 50 C.5.27

Paver 1 77 2.0 50 C.5.31


Bridge deck construction

229

Concrete mixer and pump

1 75 1.8 20 C.4.28

Vibratory poker 1 78 0.5 60 C.4.33

Diesel generator 1 65 0.5 100 C.4.83

80t Tracked Crane 1 76 2 90 C.5.37

Concrete truck (mobile)

1 per hour

108* 1.8 20 C.4.20


Surfacing (Chainage 25 – 300)

55

Paver 1 77 2.0 90 C.5.31



Footpath preparation and surfacing (Chainage 300 to 600)

33


3t Vibratory roller 1 67 1.0 50 C.5.27

Paver 1 77 2.0 50 C.5.31


Top soil verges (Chainage 600 – end)

61

25t Excavator 1 77 1.5 90 C.2.19

20t Dozer 1 81 1.2 90 C.2.12

Bridge deck

229


1 75 1.8 20 C.4.28

Vibratory poker 1 78 0.5 60 C.4.33

Diesel generator 1 65 0.5 100 C.4.83



1 per hour

108* 1.8 20 C.4.20

11

Highways

7 Possession Piling programme items

194 – 217


55t Tracked crane 1 80 2.0 100 C.3.29

Generator 1 65 0.5 100 C.4.83

8 Bored piling programme items

220 and 221

Rotary drilling rig 2 83 1.8 80 C.3.14


25t Excavator 1 77 1.5 50 C.2.19


1 75 1.8 50 C.4.28

Generator 1 65 0.5 100 C.4.83


1 per hour

108* 1.8 10 C.4.20

9 Foundation Works programme items

223, 224, 225 and 226.


1 75 1.8 100 C.4.28

Generator 1 65 0.5 100 C.4.83


1 per hour

108* 1.8 5 C.4.20

12

Highways

Page not used

13

Highways

Table F.6: Worst case predicted construction noise levels

Scenario Receptor Baseline LAeq dB

Predicted Construction LAeq dB

Total Noise Level

Noise Increase

1 Fir Tree Cottage 62.8 59.1 64.3 1.5

Crotia Mill Farm (NE) 57.0 57.1 60.1 3.1

Crotia Mill Farm (NW)

57.0 50.5 57.9 0.9

Crotia Mill Farm (SE) 57.0 57.5 60.3 3.3

Dairy House Farm 56.3 44.4 56.6 0.3

8 Fourways 56.0 50.0 57.0 1.0

6 Fourways 56.0 49.8 56.9 0.9

Newstead 59.6 53.3 60.5 0.9

Rookery Wood PH 66.9 58.5 67.5 0.6

2 Fir Tree Cottage 62.8 57.4 63.9 1.1



57.0 51.2 58.0 1.0



8 Fourways 56.0 57.5 59.8 3.8

6 Fourways 56.0 55.4 58.7 2.7

Newstead 59.6 51.2 60.2 0.6

Rookery Wood PH 66.9 54.4 67.1 0.2

3 Fir Tree Cottage 62.8 52.5 63.2 0.4



57.0 47.5 57.5 0.5



8 Fourways 56.0 41.6 56.2 0.2

6 Fourways 56.0 43.6 56.2 0.2

Newstead 59.6 47.6 59.9 0.3

Rookery Wood PH 66.9 54.6 67.1 0.2

4 Fir Tree Cottage 62.8 56.6 63.7 0.9



57.0 55.1 59.2 2.2



8 Fourways 56.0 52.2 57.5 1.5

6 Fourways 56.0 52.3 57.5 1.5

Newstead 59.6 56.6 61.4 1.8

Rookery Wood PH 66.9 55 67.2 0.3

5 Fir Tree Cottage 62.8 58.8 64.3 1.5



57.0 44.5 57.2 0.2

Crotia Mill Farm (SE) 57.0 55 59.1 2.1


8 Fourways 56.0 46.7 56.5 0.5

6 Fourways 56.0 46.7 56.5 0.5

Newstead 59.6 49.5 60.0 0.4

14

Highways

Scenario Receptor Baseline LAeq dB

Predicted Construction LAeq dB

Total Noise Level

Noise Increase

Rookery Wood PH 66.9 54.7 67.2 0.3

6 Fir Tree Cottage 62.8 59.5 64.5 1.7



57.0 51.2 58.0 1.0



8 Fourways 56.0 49.7 56.9 0.9

6 Fourways 56.0 49.5 56.9 0.9

Newstead 59.6 54.1 60.7 1.1

Rookery Wood PH 66.9 66.5 69.7 2.8

7 Fir Tree Cottage 54.6 46.1 55.2 0.6



43.9 0 43.9 0


Dairy House Farm 49.0 0 49.0 0

8 Fourways 53.6 0 53.6 0

6 Fourways 53.6 0 53.6 0

Newstead 54.4 29.8 54.4 0

Rookery Wood PH 58.5 50.4 59.1 0.6

8 Fir Tree Cottage 54.6 60.8 61.7 7.1

Crotia Mill Farm (NE) 43.9 48 49.4 5.5


43.9 0 43.9 0



8 Fourways 53.6 3.5 53.6 0

6 Fourways 53.6 3.6 53.6 0

Newstead 54.4 8.4 54.4 0

Rookery Wood PH 58.5 58.1 61.3 2.8

9 Fir Tree Cottage 54.6 49.4 55.7 1.1



43.9 0 43.9 0



8 Fourways 53.6 0 53.6 0

6 Fourways 53.6 0 53.6 0

Newstead 54.4 33.1 54.4 0

Rookery Wood PH 58.5 53.6 59.7 1.2

Highways

Appendix G - Soils, Geology and hydrogeology

Highways

Page not used

Highways

Appendix G.1 - Geo-environmental Desk Study Report

See attached CD

Highways

Page not used

Highways

Appendix H - The Water Environment

Highways

Page not used

Highways

Appendix H.1 - HAWRAT assessment Methodology

1

Highways

Page not used

1

Highways

Appendix H.1 HAWRAT Assessment

Surface Runoff Assessment

A quantitative assessment was carried out as part of the water environment assessment in the PES, which used the Water Risk Assessment Tool (HAWRAT) in order to predict the effects on receiving surface watercourses of dissolved (i.e. acute pollution) and sediment bound (i.e. chronic pollution) pollutants contained within highway runoff.

The methodology used for the HAWRAT assessment, as described in the PES, is also outlined below.

The assessment was carried out in three distinct steps:

Step 1 – Prediction of Runoff Quality

At this stage the model determined whether the discharge could contain sufficient contaminants to be an issue. This is a very simple assessment based on AADT, climatic region and site rainfall. This step concluded that road runoff needed to be assessed in more detail, thus Step 2 was required.

Step 2 – Prediction of River Impacts (after dilution and dispersion)

This stage took into account the dilution potential within the receiving watercourse from road runoff. The following additional data was required:

• Low Flow Discharge (Q95) and Base flow index (obtained using the method proposed by Institute of Hydrology (IoH) Report No. 108 [Gustard et al; (1992) Low Flow Estimation In The United Kingdom];

• Road runoff volume - Impermeable and permeable surface areas contributions to each outfall;

• Environmental importance - Basford Brook is a protected site designated as a Salmonid River under the Freshwater Fish Directive and supports populations of White Clawed Crayfish (which is an Annex II species under the Habitats Directive and a UK BAP Priority Species); and

• Water hardness - which was obtained from the EA website (What’s in your backyard? River Quality).

Step 2 also included two tiers of assessment for sediment accumulation (i.e. bound-pollutants):

• Tier 1 – Estimates the potential for sediment accumulation downstream from the outfall(s) based on the data already mentioned plus whether or not there is a structure within 100m of the outfall and an estimation of channel width. Both data were obtained from available online OS mapping.

• Tier 2 – If an outfall fails the Tier 1 test further survey data would be required of the bed width, bank and channel gradient, and Manning’s ‘n’ coefficient to facilitate a rigorous Tier 2 assessment. A Tier 2 assessment has not been required for this scheme.

Step 3 – In River Impacts Post-Mitigation

2

Highways

If a failure is predicted from Step 2, mitigation measures such as treatment will be needed to achieve an acceptable water quality. Step 3 allows treatment measures to be taken into account by applying an appropriate reduction factor. Where sustainable (vegetated) drainage systems are proposed their hybrid and bespoke nature makes it difficult to predict the treatment potential and professional judgement is required. This is supported by the results of research carried out by the Highways Agency and presented in HD45/09 and HA103/06 respectively.

Aggregation of Outfalls

The assessment first considers each outfall individually, but where outfalls are sufficiently close to have cumulative impacts, these outfalls are aggregated. Outfalls that are within 1km should be aggregated in terms of the dissolved pollutant assessment. Outfalls within 100m of each other also need to be aggregated in terms of the sediment bound pollutant assessment.

Presentation of Results

The HAWRAT assessment considered both short term and long term impacts:

• Short Term Dissolved Pollutants (acute) - The assessment compares the predicted concentration of dissolved copper and zinc against Runoff Specific Thresholds (RSTs) for 6 hours exposure and 24 hours exposure. The RSTs are summarised in Table C.1.

• Short Term Sediment Bound Pollutants (chronic) - The assessment determines whether sediment is likely to accumulate, and if so whether this is extensive.

• Long Term Impacts - The assessment compares the predicted concentrations of dissolved copper and zinc against WFD Environmental Quality Standards (See Table C.2).

Table H.1 Runoff Specific Thresholds

Zinc (ug/l) Water Hardness Band (mg/l CaC03)

Threshold Name

Copper (ug/l)

<50 50-200 >200

RST 24 Hour 21 60 92 385 RST 6 Hour 42 120 184 770

(Reproduced from Table 3.2 in HD45/09)1

Table H.2 WFD Environmental Quality Standards

Water Hardness Band (mg/l CaC03)

Dissolved Copper (ug/l) Zinc (ug/l)

0-50 1

7.8* >50-100 6 >100-250 10

>250 28

1 Note: It is assumed that beneficial impacts better than minor are unlikely to occur as a

result of the scheme and are therefore not presented.

3

Highways

(Reproduced from Table A1.1 in HD45/09)

* Proposed Value

HAWRAT produces a conservative result meaning that where a pass is predicted a high confidence can be attributed to the result. There are however, some limitations. In particular, HAWRAT was designed principally to assess non-urban trunk roads/motorways in England. Therefore, the data sets that it depends upon may not predict accurately the pollutant concentrations that might arise along urban roads. The proposed link road is semi-rural and therefore the results should be used with some care.

Spillage Risk Assessment

The spillage risk assessment was carried out following the detailed methodology described in Annex I (Method D) of HD45/09. The risk of an accident is defined as “the probability that there will be an accidental spillage of pollutant and that the pollutant will reach and impact the water body to such an extent that either a category 1 or 2 incident (a serious pollution incident) occurs.”

The assessment is based on the following data:

• The length of road (RL) for each of the categories listed in Table D.1 (HD45/09);

• The Annual Average Daily Traffic (AADT) two way flow for the design year of the new road which was obtained from the traffic data provided;

• The Heavy Goods Vehicles (HGVs) percentage, which was obtained from the traffic data provided;

• Spillage rates from Table D1.1 (HD45/09); and

• Emergency response times from Table D1.2(HD45/09).

Once the data listed above was determined the following calculations were carried out:

• The probability of a spillage (PSPL) for each length of the road was then calculated using the following formula:

( )

×××××=

−

100

%10365

9 HGVAADTSSRLP

SPL

• The total annual probability of a spillage was then calculated by adding the individual probabilities for each length of road:

∑=SPLSPL

PTP

• Finally, the annual probability of a serious incident is was given by:

POLSPLINCPTPP ×=

Being:

4

Highways

TPSPL the total annual probability of a spillage

PPOL the probability of a serious pollution incident arising as a result of a spillage (from table D1.2, HD45/09)

If annual probability of aserious pollution incident affecting a non-protected area watercourse is >1% (or greater worse than 1 in 50 years) mitigation measures to intercept and contain the spillage are required. For protected areas (e.g. SSSIs and SACs etc.) a more stringent threshold of >0.5% or in 100 years is applied.

If an unacceptable spillage risk is identified, the risk could be reduced by redesigning the road layout or changing the location of outfalls. If this is not possible containment facilities could be built into the design such as off-line storage tanks, penstocks, and ponds. Where the risk only just exceeds thresholds, containment facilities may not be required and appropriate emergency response plans could be prepared with local emergency services so that they are aware of the opportunities to block the passage of a spill before it outfalls into a watercourse.

Estimation of Low Flows (Q95)

A routine runoff assessment and a spillage risk quantitative assessments are required [in accordance with guidance in Volume 11, Section 3, Part 10 of the Design Manual for Roads and Bridges (DMRB) (HD45/09)] to assess the impact of certain road schemes on the water environment.

To allow us to carry out this assessment we required a number of variables, of which Q95 values (i.e. the flow that can be expected 95% of the time) is one of the most sensitive. The assessment method (HAWRAT) calculated both dilution of soluble pollutants and the river velocity which was then used to estimate whether sediments are likely to accumulate, and predicted the number of failures per year under a worse case situation (i.e. low flow).

Two methods can be used for obtaining Q95 values as documented in page 4/5 of HD45/09:

“Natural flows can be estimated using either the method in Institute of Hydrology (IOH) Report No. 108, or from a commercial software package called LowFlows™ available from Wallingford Hydrosolutions. Either method can be used to give a first order estimate of the natural Q95 flow, but neither is entirely reliable and judgement needs to be applied to ensure an appropriate value is used.”

Institute of Hydrology (IoH) method

This is the method that has been used for this assessment. This method estimates the Q95 using information regarding the hydrological characteristics of the upstream catchment, including standard average annual rainfall (SAAR), catchment area, base flow index (BFI), and potential evaporation (PE). These catchment descriptors can be obtained from the Flood Estimation Handbook (FEH) and from Gustard et al (1992)2.

In order to estimate mean flows, two equations can be used: either the Water Balance or the Regression Equation. When there is no record of data for most of the

2 Gustard A, Bullock A &Dixon JM (1992) Low Flow Estimation in the UK. Institute of

Hydrology Report No. 108

5

Highways

watercourses the regression equation should be used. However, both methods do give similar flow results.

Mean Flow using Water Balance:

Mean Flow (m3/s) = AARD x Catchment Area x C / Record length

Where:

AARD= SAAR – Losses

Losses= r x PE

r= 0.00061 x SAAR + 0.475 (for SAAR < 850 mm)

r = 1 (for SAAR => 850mm)

C = 3.17x10-5 for units of km2, mm and years

Mean Flow using regression equation:

Mean Flow (m3/s) = 2.7 x 10-7 x AREA1.02 x SAAR1.82 x PE-0.284

Where:

AREA = catchment area (km2)

SAAR = standard annual average rainfall (mm/yr)

PE = potential evaporation (mm/yr)

The percentage of the mean flow which forms the Q95 flow can then be estimated using the equation:

Q95:% of Mean Flow = 44.1 x BFI1.43 x SAAR-0.033 x AREA0.0342

Where:

BFI = baseflow index

The Q95 estimated values can be verified by comparing them with the flow data from monitoring sites located in close proximity to the study sites. If appropriate, estimated values can be adjusted using the flow data from nearby gauging stations.

There is some uncertainty with regards to the methods that can be used to predict Q95 flows within receiving watercourses, and no method is entirely reliable. This is important because low flow is one of the more sensitive parameters inputted into HAWRAT. A prediction of natural Q95 using a method devised by the Institute of Hydrology (see earlier) has been used by this assessment. In order to account for potential error in its prediction, the assessment for each outfall was re-run applying a 25% reduction to the predicted Q95 values.

Highways

Page not used

Highways

Appendix H.2 - WFD Objectives

1

Highways

Page not used

1

HighwaysAPPENDIX H.2 - WFD OBJECTIVES

Table H.3 Proposed Actions

Pressure Sector Improvement Required Comments

Direct biological pressures

Environment Agency; Fisheries and Angling Interests; DEFRA

Develop and deliver a programme of improvements for the most significant physical barriers to fish migration and movement through the design and installation of fish passes.

This is not applicable to the construction or operation of the proposed development. The new road will not be a barrier for fish migration.

Physical modification

Environment Agency

WFD mitigation measures manual for flood and coastal erosion risk management and land drainage activities. This manual will set out best practice options for measures to mitigate against the impacts of such activities upon ecology. This will be used to ensure that new and existing schemes and management activities will take into consideration WFD requirements and will result in minimal ecological damage.

A number of mitigation measures have been proposed in this Chapter to avoid, minimise and offset any potential adverse effects on the surface water environment.

Sediments (as a direct pollutant); Priority Hazardous Substances, Priority Substances and Specific Pollutants; Microbiology

Rivers Trusts

Aquatic Litter Programme to tackle the problem of waterborne debris including that prevalent in culverts. In some instances litter traps can be introduced on suitable rivers.

The proposed new road will incorporate structures to prevent litter entering surface water bodies. This will be done during the detailed design stage.

Sediments (as a direct pollutant); Priority Hazardous Substances, Priority Substances and Specific Pollutants; Organic pollutants

Environment Agency; Local Authorities

Promote SUDs and make guidance readily available in urban areas to reduce pollution through sediments, chemicals, oils, nutrients and to control surface water flooding. Encourage schemes like reed beds on polluted surface waters and interceptor/retention basins on road outfalls.

The proposed drainage design of the new road incorporates oil interceptors and an attenuation pond prior to discharge of surface runoff from the road to Basford Brook

2

HighwaysPressure Sector Improvement Required Comments

Sediments (as a direct pollutant);Organic Pollutants.

Urban and Transport Local Authorities

Advise planning authorities on the implementation of SUDs. Explore the issues of who owns and maintains the SUDS schemes with regard to legal, financial, health and safety concerns. Policy EM5 requires SUDS and Water Efficiency to highest contemporary standards in all new developments and encourages its retrofitting in existing ones.

The proposed road scheme incorporates SUDs techniques both during construction and operational phases of the development.

Hazardous substances and non-hazardous pollutants; Priority Substances and Specific Pollutants (Metals)

Urban and Transport

Follow the sustainable drainage systems (SUDS) Interim Code of Practice – comply with published advice for operators on sustainable drainage systems

The proposed road scheme incorporates SUDs techniques both during construction and operational phases of the development.

Physical modification

Urban and Transport Wildlife Trusts; Natural England; Local Authorities; Land managers and owners; Environment Agency

Reduce impact from hard bank reinforcement. Protect, enhance, restore & retain marginal and in channel habitats, increase habitat morphological diversity. Improve and maintain fish movement. Improve connection to floodplain. Appropriate sediment, vegetation and channel maintenance strategies. Minimise impacts from land drainage activities.

The proposed road scheme will cross Basford Brook by means of an open span bridge which helps to maintain the river ecosystem as opposed to culverted crossings.

[Source: North West River Basin Management Plan (EA, 2009)].

Highways

Appendix H.3 - Addendum to FRA

See attached CD

Highways

Page not used

Highways

Appendix H.4 - Summary of the results from the HAWRAT and spillage risk assessment

Highways

Page not used

1

Highways

ROUTINE RUNOFF AND SPILLAGE RISK ASSESSMENT

Table H.4 Summary of the Routine Runoff Assessment Step 2 – Tier 1

Outfall No

Receiving

water

course

Short Term

Long Term (WFD) Acute Impacts – Dissolved

Pollutants Chronic Impacts – Sediment Bound Pollutants

Copper Zinc

Sediment Accumu

lating

Low Flow

Vel m/s Extensive

Deposition

Index

Dissolved

Copper

EQS (ug/l)

WFD

EQS

Coppe

r (ug/l)

Dissolved

Zinc EQS

(ug/l)

WFD

EQS

Zinc

(ug/l) RT

Ss

EQ

Ss

RT

Ss

EQ

Ss

Ind

ivid

ual

2 Basford

Brook Pass Pass Pass Pass

Alert

protected

area

No 0.19 No - 0.03 28 0.12 7.8

4 Basford


Alert

protected

area

No 0.16 No - 0.01 28 0.02 7.8

6 Basford


Alert

protected

area

No 0.16 No - 0.01 28 0.05 7.8

Ag

gre

gate

d

2+4+

6 Basford

Brook Pass Pass Pass Pass N/A N/A N/A N/A N/A 0.05 28 0.19 7.8

1

Highways

Page not used

Highways

Table H.5 Spillage Risk Assessment

Ca

tch

me

nt

Ou

tfa

ll

Re

ce

ivin

g

Wa

terc

ou

rse

Highway Type/Road Stretch Road Length

(Km)

Serious

Spillage Risk

Rate per 106

HGV km/yr

Annex I Table

D1.1

AADT % HGV Pacc

Risk

Reductio

n factor

(Ppol) Ppol/year

Return

Period

risk Mitigatio

n

required

?

Spillage

risk after

Oil

Separator

Return

Period

with Oil

Separator

Further

mitigatio

n

required

?

Spillage

risk after

Pond

Return

Period

with Pond

Further

mitigation

required? Annex I

Table

D1.2

1 in

x(years)

A

2 Basford

Brook

Crewe Green Link Rd New

Roundabout North - Roundabout 0.073 5.35 9751 2.50 0.00003

2 Basford

Brook


Roundabout West - Roundabout 0.1 5.35 9751 2.50 0.00005

2 Basford

Brook


Roundabout South - Roundabout 0.1 5.35 9751 2.50 0.00005

2 Basford

Brook


Roundabout East - Roundabout 0.1 5.35 9751 2.50 0.00005

2 Basford

Brook

Crewe Green Link Rd South - No

Junction 0.355 0.31 9751 2.50 0.00001

2 Basford

Brook

Crewe Green Link Rd A500

Roundabout - Roundabout 0.1 5.35 9751 2.50 0.00005

Sub-Total 0.00023 0.45 0.00011 9,458 No 0.00005 18,916 No N/A

C

4

Basford

Brook

Crewe Green Link Rd North - No

Junction 0.134 0.31 9751 2.50 0.00000

4

Basford

Brook


Roundabout North - Roundabout 0.027 5.35 9751 2.50 0.00001

Sub-Total 0.00002 0.45 0.00001 134,281 No 0.00000 268,563 No N/A

E

6

Basford

Brook

Crewe Green Link Rd Weston Rd

Roundabout - Roundabout 0.071 5.35 9751 2.50 0.00003

6

Basford

Brook

Crewe Green Link Rd North - No

Junction 0.245 0.31 9751 2.50 0.00001

Sub-Total 0.00004 0.45 0.00002 54,794 No 0.00001 109,588 No 0.00000 219,175 No

Documents

Crewe Green Link Road (South) Environmental Statement ......• Guidelines for Landscape and Visual Impact Assessment; 2nd Edition. 2002 – LI/IEMA Spon Press; and • Interim Advice