x210165 foul drainage options report rev a march...

POTENTIAL STRATEGIC DEVELOPMENT SITE WEST OF CARTERTON OXFORDSHIRE

FOUL WATER DRAINAGE INFRASTRUCTURE OPTIONS

Hannah, Reed and Associates Limited Marlborough House High Street Kidlington OX5 2DN X210165/PHS/DKP/March 2011 Revision: A

COPYRIGHT THIS DOCUMENT MUST NOT BE COPIED OR REPRODUCED WITHOUT THE PRIOR PERMISSION OF HANNAH, REED AND ASSOCIATES LIMITED

Hannah Reed

Potential Strategic Development Site West of Carterton Foul Water Drainage Infrastructure Report Crest Nicholson Strategic Projects Revision A

X210165/PHS/DKP/August 2010 Hannah-Reed

CONTENTS PAGE NO.

1 EXECUTIVE SUMMARY 3 2 INTRODUCTION 4 3 FOUL WATER DRAINAGE OPTIONS 5 4 CONCLUSIONS AND RECOMMENDATIONS 9

APPENDICES

A Site Location Plan B Thames Water Asset Location Plans C British Geological Survey Map Extract

D Foul Water Management Strategy Options E Ground Investigation Report



1 Executive Summary Hannah Reed and Associates have carried out an investigation into the Foul Water Drainage Management aspects of a potential housing development at Carterton, West Oxfordshire. The site is identified in West Oxfordshire District Council’s Draft Core Strategy 2011 as a possible option for development, and lies to the west of the town. This report was prepared on behalf of Crest Nicholson Strategic Projects in support of a site allocation application to be submitted to West Oxfordshire District Council (WODC). The study has examined the Local Development Plan documents, which have identified a potential need for up to 1300 new dwellings. A technical appraisal has been carried out to address potential foul water drainage issues and provide possible solution options for a proposed development on land west of Carterton. The study has identified that there are two potential options for the management of foul waste water generated by the proposed development:

i. Up-grade the existing public sewer system and treatment works, following consultation with Thames Water Utilities Ltd and connect to the public foul sewer taking into consideration the peak and daily foul waste water flows.

ii. Provide an on-site foul waste water treatment plant, taking into consideration the peak and daily foul waste water flows. The on-site treatment plant could either be connected to the existing public foul sewer following limited up-grading of the existing public sewer system or be discharged to land following tertiary treatment.

The site investigation found that the soil has a permeability rate of approximately 2.59 x 10-6 m/s, which indicates that infiltration techniques such as reed beds and infiltration basins would be feasible to manage the treated discharge water. Suitable planting of native trees such as Poplars and Willow around the treatment plant and constructed wetlands would provide screening of the treatment plant from the existing and proposed residential dwellings as well as creating a habitat for native wildlife. It is concluded that the site is in a sustainable location. Some positive benefits could accrue from developing the site, including possible upgrading of the existing public sewers and sewage treatment works and improvement of the local wildlife habitats through tree planting and wetland construction.



2 Introduction West Oxfordshire District Council published their Local Development Framework (LDF) Draft Core Strategy in January 2011. The proposed development consists of the construction of approximately 1300 dwellings with associated infrastructure. The proposals also include a potential new primary school, leisure facilities and the development of the Shill Brook Valley into an ecology park. A new access road will be constructed, which incorporates a road bridge and pedestrian and cycle bridge over the Shill Brook. This report addresses the potential impact of a proposed development on land to the west of Carterton and provides strategic options to mitigate the potential options and where possible provide betterment to the site and the surrounding area.



3 Foul Drainage Options 3.1 This study has been carried out to examine the foul waste water drainage issues

which relate to the potential development of the site to the west of Carterton. See site Location Plan in Appendix A. The work has included analysis of local planning documents, Building Regulations Approved Document H, existing public sewers and treatment plants in the vicinity and the existing site’s geological and hydrological conditions to provide appropriate foul waste water management options.

3.2 Government guidance contained within DETR Circular 03/99/ WO 10/99

‘Planning requirements in respect of the use of non-mains sewerage incorporating septic tanks in new development’ and Building Regulations Approved Document H provides a hierarchy of foul wastewater drainage options that must be considered and discounted in the following order:

a. Connection to the public sewer b. Package sewage treatment plant c. Septic Tank d. If none of the above are feasible a cesspool

3.3 The proposed development consists of the construction of approximately 1300

dwellings with associated infrastructure. The proposals also include a potential new primary school, leisure facilities and the development of the Shill Brook Valley into an ecology park. A new access road will be constructed, which incorporates a road bridge and pedestrian and cycle bridge over the Shill Brook. Therefore, to allow for a possible future increase in the potential housing need, the estimation of the foul waste water peak and daily flow rates has been calculated on the assumption of 1300 dwellings with an average of 3 bedrooms.

3.4 The Peak Flow rate has been estimated in accordance with BS EN 752-1:1996

“Drain and Sewer Systems Outside Buildings”, Annex C “Calculation of Wastewater Flows for Drain Systems”.

3.5 The following should be considered when assessing the use factors and

consequential peak flow rates in a wastewater drain:

The number and type of appliances to be connected and the possibility of coincidence of discharge from different appliances

The rate of discharge from each appliance The average duration of discharge from each appliance The likely use interval of each appliance

The following empirical formula may be used:

____ Q = kDU √∑DU



Where; Q is the wastewater design flow rate, in litres per second kDU is a frequency factor, dimensionless. Typical values given in Table 3.5.1 DU is the discharge unit (a characteristic value of the rate of wastewater

outflow of a sanitary appliance), dimensionless. Typical values are given in Table 3.5.2

Table 3.5.1: Typical frequency factors (kDU): Type of Building kDU

Dwellings, guesthouses, offices (intermittent use) 0.5

Hospitals, school, restaurant, hotel (frequent use) 0.7

Toilets and/or shower open to the public (congested use) 1.0

Laboratory buildings (special use) 1.2 Table 3.5.2: Typical values of discharge units (DU): Type of Appliance DU

Washbasin, shower 0.3 to 0.6

Bath, kitchen sink 0.8 to 1.3

Dishwasher 0.2 to 0.8

Household washing machine 0.5 to 0.8

WCs 1.2 to 2.5 Table 3.5.3: The estimated Discharge Unit flow rate: Discharge Unit

Type No. Of DUs flow rate

(l/s) flow per

DU Wash hand basin 1300 0.45 585 WC single flush 1300 1.85 2405 Bath 1300 1.05 1365 Washing Machine 1300 0.65 845 Shower 1300 0.45 585 Kitchen Sink 1300 1.05 1365 Dishwasher 1300 0.50 650 ∑ DU = 7800

____ Q = 0.5 √7800 = 44.1 litres / second

3.6 The Thames Water Asset Location Plans included in Appendix B show the

locations of public sewers within the vicinity of the proposed development site. The plans show that there is a gravity sewer to the east of the site running along Upavon Way. This sewer continues for a short distance westward along the B4477 to a pumping station that discharges via a rising main.



3.7 West Oxfordshire District Council’s Draft Core Strategy Sustainability Appraisal has identified that there is no capacity at the Brize Norton Sewage pumping station, which is overwhelmed during wet weather. It also identifies that the existing sewage treatment works would require up-grading to deal with additional wastewater from a significant new development.

3.8 Therefore, in accordance with the foul waste water drainage hierarchy the

proposed development should connect to the public sewer and include proposals for up-grading of the existing foul drainage system and sewage treatment plant following consultation with Thames Water Utilities Ltd.

3.9 The proposed site is of sufficient size to provide its own on-site waste water

treatment. Therefore, in accordance with the foul waste water drainage hierarchy, if following consultation with Thames Water Utilities it is not feasible to up-grade the existing sewer system and treatment works, an on-site treatment plant could be provided. See possible location of on-site treatment plant in Appendix D.

3.10 The size of the treatment plant should be based on the peak and daily flow

produced by the proposed 1300 dwelling development. The peak flow has been estimated in section 3.5. The daily flow has been estimated on the assumption that the proposed dwellings will have an average of 3 bedrooms.

3.11 The British Water Code of Practice, suggests that a daily foul flow volume of 180

litres per person per day should be used for the sizing of treatment systems for residential dwellings.

A 3 bedroom dwelling is estimated to house 5 people. Therefore, a 1300 dwelling estate would produce a daily foul waste water flow of: 180(1300x5) = 1,170,000 litres per day or 1170m3/day. This equates to an average foul waste water flow of 13.5 l/s. 3.12 It may be possible to discharge the treated effluent to the existing Thames Water

sewer system and treatment works following the up-grading of the existing public sewers’ and treatment plant’s capacities.

3.13 If following consultation it is not possible to discharge the treated effluent to the

public sewer it could be possible to discharge the effluent to land following tertiary treatment such as constructed wetlands or reed beds, which significantly reduce chemicals in the discharge and consequently also significantly reduce odours.

3.14 The British Geological Survey Map Sheet 236 for Witney, an extract of which is

included in Appendix C, indicates that the site is underlain by Cornbrash and Forest Marble, which is in turn underlain by White Limestone.



3.15 A ground investigation was carried out at the site to confirm the geology and the permeability of the soil, which would assist in determining if it would be appropriate to utilise infiltration techniques to mitigate the and manage the treated discharge water , e.g. soakaways, infiltration basins and reed beds.

3.16 The site investigation confirmed that the site has a capping of topsoil over Forest

Marble. Forest Marble consists of thin layers of clayey and sandy limestone brash and sandy clay resting upon weak to moderately strong thinly and thickly bedded limestone rock. The limestone rock layer resisted penetration by the excavation equipment used

3.17 Cornbrash and Forest Marble are moderately permeable and have typical

permeability rates of 1.0x10-5m/s and 3.5x10-6m/s respectively. As a result the geological conditions at the site are likely to be suitable for infiltration techniques, which would allow discharge to land.

3.18 The site investigation found that the soil has a permeability rate of approximately

2.59 x 10-6 m/s, which indicates that infiltration techniques such as reed beds and infiltration basins would be feasible to manage the treated discharge water.

3.18 Suitable planting of native trees such as Poplars and Willow around the treatment

plant and constructed wetlands would provide screening of treatment plant from the existing and proposed residential dwellings as well as creating a habitat for native wildlife.



4 Conclusions and Recommendations 4.1. The study has identified that there are two potential options for the management

of foul waste water generated by the proposed development:

i. Up-grade the existing public sewer system and treatment works, following consultation with Thames Water Utilities Ltd and connect to the public foul sewer taking into consideration the peak and daily foul waste water flows.

ii. Provide an on-site foul waste water treatment plant, taking into consideration the peak and daily foul waste water flows. The on-site treatment plant could either be connected to the existing public foul sewer following limited up-grading of the existing public sewer system or be discharged to land following tertiary treatment.

4.2. Cornbrash and Forest Marble are moderately permeable and have typical permeability rates of 1.0x10-5m/s and 3.5x10-6m/s respectively. As a result the geological conditions at the site are suitable for infiltration techniques, which would allow discharge to land.

4.3 A ground investigation was carried out at the site to confirm the geology and the

permeability of the soil, which would assist in determining if it would be appropriate to utilise infiltration techniques to mitigate the and manage the treated discharge water , e.g. soakaways, infiltration basins and reed beds.

4.4 The site investigation confirmed that the site has a capping of topsoil over Forest

Marble. Forest Marble consists of thin layers of clayey and sandy limestone brash and sandy clay resting upon weak to moderately strong thinly and thickly bedded limestone rock. The limestone rock layer resisted penetration by the excavation equipment used

4.5 Cornbrash and Forest Marble are moderately permeable and have typical

permeability rates of 1.0x10-5m/s and 3.5x10-6m/s respectively. As a result the geological conditions at the site are likely to be suitable for infiltration techniques, which would allow discharge to land.

4.6 The site investigation found that the soil has a permeability rate of approximately

2.59 x 10-6 m/s, which indicates that infiltration techniques such as reed beds and infiltration basins would be feasible to manage the treated discharge water.

4.7 Suitable planting of native trees such as Poplars and Willow around the treatment

plant and constructed wetlands would provide screening of the treatment plant from the existing and proposed residential dwellings as well as creating a habitat for native wildlife.



Appendix A Site Location Maps



Land West of Carterton Site Location Maps

Grid Coordinates 426800mE 206600mN



Appendix B Thames Water Asset Location Plans

Asset Location Search

Page 1 of 54

Thames Water Utilities Ltd Property Insight PO Box 3189 Slough SL1 4WW DX 151280 Slough 13 T 0118 925 1504 F 0118 923 6655/57 E [email protected] www.twpropertyinsight.co.uk Registered in England and Wales No. 2366661, Registered office Clearwater Court, Vastern Road Reading RG1 8DB

Debbie Prichard Hannah Reed and Associates Ltd Marlborough House High Street OXFORD OX5 2DN

Search address supplied Land West Of

Carterton Oxfordshire

Your reference X210165 Our reference ALS/ALS Standard/2010_1812670 Search date 13 May 2010

OUR PRICES WILL BE CHANGING FROM 1st APRIL 2010. Thames Water Property Insight will be increasing the price of its Asset Location Search as indicated below. Prices with effect from 1st April 2010 are as follows: Site Size (m2) Price (excl. VAT) STANDARD Price (excl. VAT) 24-HOUR RESPONSE 0-250,000 £46.00 £91.60 250,001-500,000 £92.00 £183.20 500,001-750,000 £138.00 £274.80 750,001-1,000,000 £184.00 £366.40 Over 1,000,000 Price on application Price on application To avoid delays, please ensure that relevant personnel within your company are made aware of these changes as appropriate. If you require any further information or have any queries, please do not hesitate to contact the Customer Support Team on 0118 925 1504. Credit card payments are available. Please phone 01189 251509 You are now able to order your Asset Location Search requests online by visiting www.twpropertyinsight.co.uk


Page 2 of 54


Search address supplied: Land West Of, Carterton, Oxfordshire, Dear Sir / Madam An Asset Location Search is recommended when undertaking a site development. It is essential to obtain information on the size and location of clean water and sewerage assets to safeguard against expensive damage and allow cost-effective service design. This search provides maps showing the position, size of Thames Water assets close to the proposed development and also manhole cover and invert levels, where available. Please note that none of the charges made for this report relate to the provision of Ordnance Survey mapping information. The replies contained in this letter are given following inspection of the public service records available to this company. No responsibility can be accepted for any error or omission in the replies. You should be aware that the information contained on these plans is current only on the day that the plans are issued. The plans should only be used for the duration of the work that is being carried out at the present time. Under no circumstances should this data be copied or transmitted to parties other than those for whom the current work is being carried out. Thames Water do update these service plans on a regular basis and failure to observe the above conditions could lead to damage arising to new or diverted services at a later date. Contact Us If you have any further queries regarding this enquiry please feel free to contact a member of the team on 0118 925 1504, or use the address below: Thames Water Utilities Ltd Property Insight Tel: 0118 925 1504 PO Box 3189 Fax: 0118 923 6657 Slough SL1 4WW Email: [email protected] Web: www.twpropertyinsight.co.uk


Page 3 of 54


Waste Water Services

Please provide a copy extract from the public sewer map. The following quartiles have been printed as they fall within Thames' sewerage area: SP2605SW SP2605NW SP2606SW SP2606NW SP2607SW SP2605SE SP2605NE SP2606SE SP2606NE SP2607SE SP2706SW SP2706NW SP2707SW SP2707SE Enclosed is a map showing the approximate lines of our sewers. Our plans do not show sewer connections from individual properties or any sewers not owned by Thames Water unless specifically annotated otherwise. Records such as "private" pipework are in some cases available from the Building Control Department of the relevant Local Authority. Where the Local Authority does not hold such plans it might be advisable to consult the property deeds for the site or contact neighbouring landowners. This report relates only to sewerage apparatus of Thames Water Utilities Ltd, it does not disclose details of cables and or communications equipment that may be running through or around such apparatus. The sewer level information contained in this response represents all of the level data available in our existing records. Should you require any further Information, please refer to the relevant section within the 'Further Contacts' page found later in this document. For your guidance: • The Company is not generally responsible for rivers, watercourses,

ponds, culverts or highway drains. If any of these are shown on the copy extract they are shown for information only.

• Sewers indicated on the extract of the public sewer map as being subject to an agreement under Section 104 of the Water Industry Act


Page 4 of 54


1991 are not an ‘as constructed’ record. It is recommended that these details are checked with the developer.

Clean Water Services

Please provide a copy extract from the public water main map. The following quartiles have been printed as they fall within Thames' water area: SP2605SW SP2605NW SP2606SW SP2606NW SP2607SW SP2605SE SP2605NE SP2606SE SP2606NE SP2607SE SP2706SW SP2706NW SP2707SW SP2707SE Enclosed is a map showing the approximate positions of our water mains and associated apparatus. Please note that records are not kept of the positions of individual domestic supplies. For your information, there will be a pressure of at least 10m head at the outside stop valve. If you would like to know the static pressure, please contact our Customer Centre on 0845 920 0800. The Customer Centre can also arrange for a full flow and pressure test to be carried out for a fee. For your guidance: • Assets other than vested water mains may be shown on the plan, for

information only. • If an extract of the public water main record is enclosed, this will show

known public water mains in the vicinity of the property. It should be possible to estimate the likely length and route of any private water supply pipe connecting the property to the public water network.


Page 5 of 54


Payment for this Search An invoice is enclosed. Please send remittance to Thames Water Utilities Ltd., PO Box 223, Swindon, SN38 2TW.


Page 6 of 54


Further contacts:

Waste Water queries

Should you require verification of the invert levels of public sewers, by site measurement, you will need to approach the relevant Thames Water Area Network Office for permission to lift the appropriate covers. This permission will usually involve you completing a TWOSA form. For further information please contact our Customer Centre on Tel: 0845 920 0800. Alternatively, a survey can be arranged, for a fee, through our Customer Centre on the above number. If you have any questions regarding sewer connections, building over issues or any other questions regarding operational issues please direct them to our service desk. Which can be contacted by writing to:

Developer Services (Waste Water) Thames Water Clear Water Court Vastern Road Reading RG1 8DB Tel: 0845 850 2777 Fax: 0118 923 6613 Email: [email protected]

Should you require any further information regarding budget estimates, diversions or stopping up notices then please contact:

DevCon Team Asset Investment Thames Water Maple Lodge STW Denham Way Rickmansworth Hertfordshire WD3 9SQ Tel: 01923 898 072 Fax: 01923 898 106 Email: [email protected]


Page 7 of 54


Clean Water queries Should you require any advice concerning clean water operational issues or clean water connections, please contact our Kew Service Desk by writing to:

Clean Water Design Thames Water Utilities 1 Kew Bridge Road Brentford Middlesex TW8 0EF

Tel: 0845 850 2777 Fax: 0208 213 8833 Email: [email protected]

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Asset Location Search Sewer Map - ALS/ALS Standard/2010_1812670 SP2605SW

FW

Def

Issues

1.22m FW

85.9m

88.6m

88.9m

GP

War

d Bdy

1.22m RH

B 44

7 7

1.22m

RH

FW

The width of the displayed area is 500m and the centre of the map is located at OS coordinates 426250,205250 The position of the apparatus shown on this plan is given without obligation and warranty, and the accuracy cannot be guaranteed. Service pipes are not shown but their presence should be anticipated. No liability of any kind whatsoever is accepted by Thames Water for any error or omission. The actual position of mains and services must be verified and established on site before any works are undertaken. Based on the Ordnance Survey Map with the Sanction of the controller of H.M. Stationery Office, License no. WU298557 Crown Copyright Reserved.

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NB. Levels quoted in metres Ordnance Newlyn Datum. The value -9999.00 indicates that no survey information is available

Manhole Reference Manhole Cover Level Manhole Invert Level N/a

n/a

n/a

The position of the apparatus shown on this plan is given without obligation and warranty, and the accuracy cannot be guaranteed. Service pipes are not shown but their presence should be anticipated. No liability of any kind whatsoever is accepted by Thames Water for any error or omission. The actual position of mains and services must be verified and established on site before any works are undertaken.

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Asset Location Search Sewer Map - ALS/ALS Standard/2010_1812670 SP2605NW

SS

96.3m

88.8m


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n/a

n/a


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100.4m

98.6m


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n/a

n/a


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Field Farm

Alvescot

101.2m

100.9m

101.3m

100.2m

CR

ED & Ward Bdy

Alvescot Field

Alvescot StudCottage

Stable Cottage

Farm House

The Bungalow


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n/a

n/a


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101.6m

99.4m

CR


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n/a

n/a


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Asset Location Search Sewer Map - ALS/ALS Standard/2010_1812670 SP2605SE

Springfield House

FB

91.1mGP

Football Ground

Runway Approach Lights

B 4020

Rosebarn Cottage

(kennels)

GP

B 40

20


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n/a

n/a


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Asset Location Search Sewer Map - ALS/ALS Standard/2010_1812670 SP2605NE

92.5m

93.6m

94.9m

GP

Lay-by

B 4477


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n/a

n/a


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Kenns Farm

90.8m

B 4477

B 44

77


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n/a

n/a


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Asset Location Search Sewer Map - ALS/ALS Standard/2010_1812670 SP2606NE

Alvescot Down

Path

(um

)


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n/a

n/a


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Alvescot Down

Alvescot Downs Farm Cottages

Path ( um)

1 2


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n/a

n/a


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300

150

225

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Manhole Reference Manhole Cover Level Manhole Invert Level 4201 4301 4401 4402 3001 4001 3101 3102 3201 2201 2303 2302 2301 3304 3302 3303 3301 3402 3401 4002 4101 - 4102

94.73 95.12 94.53 96.75 87.09 90.22 n/a n/a n/a n/a 85.2 85.84 85.72 87.98 89.01 91.19 92.01 n/a 91.67 93.74 93.44 - 93.63

93.72 93.1 92.65 95.07 84.19 88.92 n/a n/a n/a n/a 83.01 84.04 83.97 85.33 87.01 89.32 89.06 n/a 89.67 91.49 91.89 - 92.14


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150

150

150

225

150

150

225

225

150

225

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225

225

225150

150

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150

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45024503

4504

4804

4805

49044903

2901

2801

2802

2701

3904

3602

3801

3902

2702

3601

3501

3903

3603

3901

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3502

3503

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Def

LB

TCB

St Joseph's

CS

98.5m98.8m

98.6m

92.0m

94.5m

96.3m

97.3m

Balancing Tank

School, Carterton

El Sub S

ta

Playground

Catholic Primary

SM

UPAV

ON

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77

PLACE

STIR

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WIN

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30

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1

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23

40

26

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31

17

37

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63

10

33

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20

70

19

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24

76

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71

90

96

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6

4

1

20

EDGEWORTH

CARR

27

78

81

85

91

97

74

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El Sub Sta


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Manhole Reference Manhole Cover Level Manhole Invert Level 4902 4801 4802 2901 2801 2802 2701 2702 3601 3902 3904 3801 3602 3903 3901 3603 3701 3702 3604 4901 4503 4504 4803 4804 4805 4904 4903 4505 4506 4502 3503 3502 3501 4501

98.41 98.2 97.85 98.61 98.11 97.22 97.58 96.72 n/a 99 98.95 98.51 94.13 99.15 99.33 94.47 97.69 98 96.07 98.69 98 97.98 97.9 97.81 97.87 98.15 98.44 96.67 98.07 97.97 92.51 92.29 n/a 96.41

95.76 96.3 94.66 93.91 93.56 93.22 n/a 93.64 n/a 94 95.8 96.36 91.88 94.11 96.83 92.89 94.23 94.44 93.37 94.49 94.94 95.33 94.71 95.13 95.27 94.7 94.54 94.94 96.11 94.7 91.71 90.51 n/a 94.07


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900

900

150

150

150

150

225150

150

150

375 ASSUMED ROUTE AND OUTFALL

900225

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%

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3404

3403

3401

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4201

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4001

3001

3002

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4103

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4101

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Alvescot Down

Downs Farm

101.4m

100.7m

100.0m

99.3m

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War

d Bd

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El Sub Sta

Playgrou

nd

B 44

77

STIR

LIN

G

FALC

ON

CLO

SE

HERON CLO

SE

Sunset View

25

1

14

15

20

13

30

7

8

19

21

10

6

5

3

30

14

1

13

7

8W

ARW

ICK

CLO

SE

CLO

SE


of 54


Manhole Reference Manhole Cover Level Manhole Invert Level 4102 4101 4203 4201 4202 4104 4103 3404 3001 3002 3403 3401 4401 4001 - 4002

100.65 100.88 101.26 100.97 100.91 101.23 101.36 90.05 99.65 99.97 100.69 100.58 101.41 99.43 - 100.21

98.85 98.68 97.96 96.57 97.56 98.98 98.41 88.37 97.75 98.27 97.81 98.79 98.86 97.88 - 98.66


of 54


10-64971

PROPOSED NETWORK PENDING ADOPTIONAGREEMENT/LEADBITTER CONSTR/10-29935

SYCAMORE DRIVE

AS CONSTRUCTED NETWORK UNDER ADOPTIONAGREEMENT. OXFORD CITIZENS HA

BURFORD ROAD CARTERTON150

225

150

150

150

150

225

150

225

150

225

150

15015

0150

150

225

150

150

300

150

150

150

150

225

150 150

225

225

150150

225

TO BE

ABANDONED

150

225

150

100

1 3

150

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150

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8301

930284078406

84108408

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8402

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5201

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9401

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9102

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9101

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8013

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8114

8020

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8106

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8025

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8023

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7101 8105

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71027107

81017108 81028109 8115

81107109 812081198103811181048117 81168112

81187111 7110

720372027201 82078206

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8205

8208

8302

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5105

5001

5102

5103

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CARTERTON

College

Community

Carterton

101.3m

100.3m

99.3m

98.3m

99.8m

96.2m

99.2m

98.8m

ED &

Ward B

dy

El Sub Sta

Playground

UPAVON WAY

DRIVE

B 4477

KESTREL CLOSE PLACE

CLOSE

DOVETREES

NORTHOLT ROAD

LORD

CLOSE

LIME TREE CLOSE

RO

CK

CLO

SEROCK ROAD

FINC

HD

ALE

CLO

SE

LAUREL

BUR

FORD

RO

AD

SYC

AM

OR

E D

RIV

E

POU

LTN

EY

Blaiford

House

Corner House

Blenheim

94.6m

Fairseat

Court

11

9 to 11

116

110

1 to 25

35 to 45

23 to 33

1

6

34

3

14

20

39

8

28

15

12

22

13

35

66

18

50

23

47

3129 30

24

26

32

9

5

75

51

49

120

7

2

21

45

38

10

58

37

17

100

92

19

108

25

88

46

40a

56

16

42

78

63

44

59

27

33

4102

10436

40b

40

65

18

13

2

14

23

1

14

33

35

66

2228

11

1

4

15

37

12

14

32

15

11

31

14

22

26

14

11

7

El Sub S

ta

51

45

1

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4

4

21

24

24

2

12

El Sub S

ta

1

17

11

27

16

6

1

42

39

1

El Sub Sta

14

31

11

7

38

1

1

14

8

22

12

7

6

3

35

14

28

5

1

63

B 4020

FAULDER AVENUE

ROWAN CLOSE

ROBINSON CLOSE

MERLIN CLOSE

ST JOHN'S

118

SYCAMORE

15 to 21

18

2

21

122

9098

42

5768

1

CLO

SE

El Sub Sta

23

4027

28

UPAVON WAY

15

7


of 54


Manhole Reference Manhole Cover Level Manhole Invert Level 8401 9001 9302 9002 9301 8008 8009 8024 8025 8101 7201 8207 8206 8201 7204 8406 9401 9201 8007 8015 8105 8102 8109 8103 8118 8004 8012 8016 8017 8019 8020 8021 8106 8208 8410 8403 8023 8107 8108 8110 8111 8112 8202 8302 8407 8405 8011 8005 8010 8006 8402 8018 9102 9202 5101 5102 5105 5103 5104 5201 5202 6201 6102 6401 6001 6103 6104 6301 6002 6004 6005 6108 7103 6101 6504 9403 9101 9003 9303 7106 7002 7105 8301 8204 8119 8003 8013 8116 8205 8114 8404

100.04 95.82 99.74 95.57 98.07 96.58 96.81 96.71 97.18 100.81 98.46 98.42 98.37 98.02 98.46 n/a 100.2 96.55 96.18 96.52 96.78 97.09 97.19 97.24 97.49 95.68 n/a n/a 95.76 n/a 96 96.42 96.25 97.04 98.43 101.59 96.67 96.6 96.91 97.33 97.6 97.6 97.83 101.59 n/a n/a 95.5 95.5 95.29 95.36 100.37 n/a 95.13 95.62 99.65 100.77 100.98 100.93 100.44 101.32 101.17 100.91 99.87 101.03 99.28 99.82 99.85 100.56 n/a n/a n/a 99.29 n/a n/a 101.04 100.79 94.47 94.08 98.67 99.25 n/a 98.89 98.89 97.78 97.06 96.13 96.11 96.98 97.76 96.26 n/a

96.99 94.54 96.8 94.73 96.27 95.21 95.51 95.09 95.43 99.45 97.28 97.13 96.93 95.84 96.51 97.08 97.55 94.27 94.86 94.63 94.84 95.56 95.32 95.6 96.44 94.07 n/a n/a 94.27 n/a 95.1 95.04 95.15 95.09 96.34 97.59 94.67 94.72 95.06 95.94 96.28 96.43 96.17 100.63 96.88 n/a 93.84 94.03 93.69 94.62 97.12 n/a 93.28 93.61 95.55 95.92 96.18 97.18 97.64 97.17 97.72 98.06 99.28 99.54 97.5 99.47 99.41 98.61 n/a n/a n/a 98.32 n/a n/a 99.78 98.22 93.25 92.08 96.95 98.6 n/a 98.03 97.14 96.41 96.03 94.24 94.28 96.2 96.61 95.03 n/a

of 54

Manhole Reference Manhole Cover Level Manhole Invert Level 8409 8104 7001 7005 7101 7102 7110 7203 7202 7003 7004 7107 7108 7109 7111 9402 8408 8001 8014 8117 8203 8002 8120 8113 8022 8115 5001 5002

n/a 96.95 97.51 97.3 98.3 97.87 98.9 98.81 98.5 n/a n/a 98.93 n/a n/a n/a 100.39 n/a 96.47 96.36 97.45 n/a 96.41 97.2 96.73 96.42 97.17 99.05 98.71

96.43 95.85 96.47 95.56 96.72 96.47 97.73 97.59 97.39 n/a n/a 98.12 n/a n/a n/a 98.06 96.68 94.6 94.42 96.16 n/a 94.51 95.75 94.84 94.45 95.74 94.95 95.26


of 54

ALS Sewer Map Key

Foul: A sewer designed to convey waste water from domestic andindustrial sources to a treatment works.

Surface Water: A sewer designed to convey surface water (e.g. rainwater from roofs, yards and car parks) to rivers or watercourses.

Combined: A sewer designed to convey both waste water and surfacewater from domestic and industrial sources to a treatment works.

Trunk Surface Water

Storm Relief

Vent Pipe

Proposed Thames SurfaceWater Sewer

Gallery

Surface Water RisingMain

Sludge Rising Main

Vacuum

Public Sewer Types (Operated & Maintained by Thames Water)

Notes:1) All levels associated with the plans are to Ordnance Datum Newlyn.

2) All measurements on the plans are metric.

3) Arrows (on gravity fed sewers) or flecks (on rising mains) indicate direction offlow.

4) Most private pipes are not shown on our plans, as in the past, this information hasnot been recorded.

5) ‘na’ or ‘0’ on a manhole level indicates that data is unavailable.

Trunk Foul

Trunk Combined

Bio-solids (Sludge)

Proposed Thames WaterFoul Sewer

Foul Rising Main

Combined Rising Main

Proposed Thames WaterRising Main

Sewer FittingsA feature in a sewer that does not affect the flow in the pipe. Example: a ventis a fitting as the function of a vent is to release excess gas.

Operational ControlsA feature in a sewer that changes or diverts the flow in the sewer. Example:A hydrobrake limits the flow passing downstream.

Air Valve

Dam Chase

Fitting

Meter

Vent Column

Control Valve

Drop Pipe

Ancillary

Weir

End ItemsEnd symbols appear at the start or end of a sewer pipe. Examples: anUndefined End at the start of a sewer indicates that Thames Water has noknowledge of the position of the sewer upstream of that symbol, Outfall on asurface water sewer indicates that the pipe discharges into a stream or river.

Outfall

Undefined End

Inlet

Other SymbolsSymbols used on maps which do not fall under other general categories

Summit

Public/Private Pumping Station/

Invert Level

Change of characteristic indicator (C.O.C.I.)

Other Sewer Types (Not Operated or Maintained by Thames Water)

Areas

Lines denoting areas of underground surveys, etc.

Agreement

Chamber

Operational Site

Conduit Bridge

Foul Sewer

Combined Sewer

Culverted Watercourse

Surface Water Sewer

Gulley

Proposed

Abandoned Sewer

Tunnel

6) The text appearing alongside a sewer line indicates the internal diameter ofthe pipe in milimetres. Text next to a manhole indicates the manholereference number and should not be taken as a measurement. If you areunsure about any text or symbology present on the plan, please contact amember of Property Insight on 0118 925 1504.

P PM

W

of 54

Asset Location Search Water Map - ALS/ALS Standard/2010_1812670 SP2605SW

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Def

Issues

1.22m FW

85.9m

88.6m

88.9m

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B 44

77

1.22m

RH

FW


of 54

Asset Location Search Water Map - ALS/ALS Standard/2010_1812670 SP2605NW

SS

96.3m

88.8m


of 54


100.4m

98.6m


of 54


6" S

TR

ATE

GIC

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Field Farm

Alvescot

101.2m

100.9m

101.3m

100.2m

CR

ED & Ward Bdy

Alvescot Field

Alvescot StudCottage

Stable Cottage

Farm House

The Bungalow


of 54


6"

6"

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101.6m

99.4m

CR


of 54

Asset Location Search Water Map - ALS/ALS Standard/2010_1812670 SP2605SE

Springfield House

FB

91.1mGP

Football Ground

Runway Approach Lights

B 4020

Rosebarn Cottage

(kennels)

GP

B 40

20


of 54

Asset Location Search Water Map - ALS/ALS Standard/2010_1812670 SP2605NE

1985

STR

ATEG

IC 2

00m

m D

I

92.5m

93.6m

94.9m

GP

Lay-by

B 4477


of 54


200m

m S

TRAT

EGIC

Kenns Farm

90.8m

B 4477

B 44

77


of 54

Asset Location Search Water Map - ALS/ALS Standard/2010_1812670 SP2606NE

6" STRATEGIC

Alvescot Down

Path

(um

)


of 54


Alvescot Down

Alvescot Downs Farm Cottages

Path ( um)

1 2


of 54


100mm

(198

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91.6m

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Chapel of

Track

Pumping Station

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23

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MINTY CLOSE

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97.7

29


of 54


4"

6"

4"

4"

4"

3"

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4"

4"

3"

4"

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Def

LB

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St Joseph's

CS

98.5m98.8m

98.6m

92.0m

94.5m

96.3m

97.3m

Balancing Tank

School, Carterton

El Sub S

ta

Playground

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23

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63

10

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70

19

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80

75

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96

22

19

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CLO

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59 30

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CLO

SE

1

23

14

14

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6

El Sub Sta

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1

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78

81

85

91

97

74

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of 54


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Alvescot Down

Downs Farm

101.4m

100.7m

100.0m

99.3m

Pond

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War

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El Sub Sta

Playgrou

nd

WAR

WIC

K C

LOS

E

B 44

77

STIR

LIN

GC

LOS

E

FALC

ON

CLO

SE

HERON CLO

SE

Sunset View

25

1

14

15

20

13

30

7

8

19

21

10

6

5

3

30

14

1

13

7

8


of 54


4"

125mm

80mm

100m

m

90mm

100mm

DISINFECTION TAPPING

3"

4"

4"

4"

100mm ST

100m

3"

3"

3"

3"

3"

3"

3"3"

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100mm

6"

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3"3"

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CARTERTON

College

Community

Carterton

101.3m

100.3m

99.3m

98.3m

99.8m

96.2m

99.2m

98.8m

ED &

Ward B

dy

El Sub Sta

Playground

UPAVON WAY

DRIVE

B 4020

B 4477

KESTREL CLOSE PLACE

FAULDER AVENUE

CLOSE

DOVETREES

ROWAN CLOSE

NORTHOLT ROAD

LORD

CLOSE

LIME TREE CLOSE

RO

CK

CLO

SEROCK ROAD

FINC

HD

ALE

CLO

SE

LAUREL

BUR

FORD

RO

AD

ROBINSON CLOSE

SYC

AM

OR

E D

RIV

EMERLIN CLOSE

POU

LTN

EY

Blaiford

House

Corner House

Blenheim

94.6m

Fairseat

Court

11

9 to 11

116

110

SYCAMORE

1 to 25

35 to 45

23 to 33

1

6

34

3

14

20

39

8

28

15

12

22

13

35

66

18

50

23

47

3129 30

24

26

32

9

5

75

51

49

120

7

2

21

45

38

10

122

37

17

100

92

19

108

25

88

46

40a

56

16

42

78

57

63

44

59

27

33

4102

10436

40b

40

65

12

31

El Sub Sta

El Sub S

ta

1

18

21

15

14

38

14

1

11

22

18

1

4

17

32

15

1

11

4

35

14

11

23

11

14

1

26

5

7

23

16

21

13

4

33

2

24

24

2

1211

7

37

15

28

27

16

39

14

42

8

1

El Sub Sta

14

31

22

El Sub S

ta

12

45

1

1

14

8

35

22

2

6

3

66

14

28

51

1

7

63

ST JOHN'S

118

15 to 21

58

9098

42

68

28

CLO

SE

7

4027

UPAVON WAY


of 54

ALS Water Map Key

PIPE DIAMETER DEPTH BELOW GROUND

Up to 300mm (12”) 900mm (3’)

300mm - 600mm (12” - 24”) 1100mm (3’ 8”)

600mm and bigger (24” plus) 1200mm (4’)

DistributionMain: The most common pipe shown on water maps.With few exceptions, domestic connections are only made todistribution mains.

Trunk Main: A main carrying water from a source of supply to atreatmentplant or reservoir, or from one treatmentplant or reservoirto another. Also a main transferring water in bulk to smaller watermains used for supplying individual customers.

Supply Main: A supply main indicates that the water main is usedas a supply for a single property or group of properties.

Fire Main: Where a pipe is used as a fire supply, the word FIRE willbe displayed along the pipe.

Metered Pipe: A metered main indicates that the pipe in questionsupplies water for a single property or group of properties and thatquantity of water passing through the pipe is metered even thoughthere may be no meter symbol shown.

Transmission Tunnel: A very large diameter water pipe. Mosttunnels are buried very deep underground. These pipes are notexpected to affect the structural integrity of buildingsshown on themap provided.

ProposedMain: A main that is still in the planningstages or in theprocess of being laid. More details of the proposed main and itsreference number are generally included near the main.

Water Pipes (Operated & Maintained by Thames Water)

HydrantsSingle Hydrant

MetersMeter

ValvesGeneral PurposeValve

Air Valve

End ItemsSymbol indicating what happens at the end of �a water main.

Blank Flange

Capped End

Undefined End

Manifold

Customer Supply

Fire Supply

Emptying Pit

Operational SitesBooster Station

Other

Other (Proposed)

Pumping Station

Service Reservoir

Shaft Inspection

TreatmentWorks

Unknown

Other Symbols

Other Water Pipes (Not Operated or Maintained by Thames Water)

Data Logger

Other Water Company Main: Occasionally other water companywater pipes may overlap the border of our clean water coveragearea. These mains are denoted in purple and in most cases havethe owner of the pipe displayed along them.

Private Main: Indiates that the water main in question is not ownedby Thames Water. These mains normally have text associated withthem indicating the diameter and owner of the pipe.

3” SUPPLY

3” FIRE

3” METERED

L

CF

4”

16”

Water Tower

?

Pressure ControlValve

CustomerValve


X210165/PHS/DKP/August 2010 Page 13 Hannah-Reed

Appendix C British Geological Survey Map Extract



British Geological Map Sheet 236 – Witney

Key: Alluvium Cornbrash Forest Marble with Limestone Forest Marble Oxford Clay

FMb (L)

KlC

FMb

CB



Appendix D Foul Water Management Options



Appendix E Site Investigation Report

Geotechnical andGeoenvironmentalConsultants

GROUND Our Ref: S.3909

INVESTIGATIONSERVICES Your Ref:

28 February 2011Debbie PrichardHannah-ReedMarlborough HouseHigh StreetKidlingtonOX5 2DN

Dear Debbie

PERMEABILITY TESTING - LAND WEST OF CARTERTON, OXFORDSHIRE

We have completed the soil infiltration tests in respect of the above and accordinglyenclose location plan, trial pit logs and permeability test results.

In summary, three trial pits were excavated to depths of between 1.40m and 1.80m.Each pit was then filled with potable water which was allowed to drain whilemeasurements of the falling head were recorded over a three day period.

The results of the excavation work reveal the geology to comprise a capping oftopsoil over Forest Marble, which consists of thin layers of clayey and sandylimestone brash and sandy clay resting upon weak to moderately strong thinly andthickly bedded limestone rock. This rock layer resisted penetration by theexcavation equipment in TP2 and TP3. TP2 and TP3 remained dry duringexcavation work while in TP1 perched groundwater was recorded entering the pit at0.60m depth.

The results of the permeability testing indicate the Forest Marble has a low tomedium permeability classification with calculated soil infiltration rates of 4.23 x10-7 m/sec and 2.59 x 10-6 m/sec. The infiltration rate in TP1 was not calculated duelack of robust data.

15 Bostock Road, Abingdon, Oxon OX14 1DPTel (01235) 521631 Fax (01235) 553972Web: www.gis-geotec.come-mail: [email protected]

Hannah-Reed Permeability testing -Land west of Carterton,

28 February 2011 Report No. S.3909 Oxfordshire

Martyn Paul Boughton BSc (Hons) Julian M Huxham BSc (Hons)FGS

Page 2

PERMEABILITY ASSESSMENT AND SOAKAWAY DESIGN

Surface water currently infiltrates the open soft landscaping either percolatingdirectly into the soil fabric or via surface runoff down gradient into channels andvalleys.

There were areas of surface flooding and pooling developed around localiseddepressions or in areas where the ground topography was either flat or level withconsequential slow vertical infiltration of surface water into the soil.

New development at the site is likely to increase the rate of surface runoff ifdrainage waters are discharged directed into localised soakage chambers withoutsome degree of attenuation. The implications of the development on surface waterrunoff will be evaluated via a Flood Risk Assessment (FRA) however that is likely toconclude that the drainage strategy for the site should be based on a preference forrainwater harvesting and infiltration drainage with attenuation to mitigate thepotential for increased run off.

In consideration of the drainage area (for example 50m2) and the permeability testresults, the following table provides indicative infiltration drainage design.

Table 1 – Indicative Infiltration Drainage Design

Infiltration TestLocation and depth

Slowest InfiltrationRate

Soakaway for 50m2

Impermeable Area for 1in30 year up to 24 hour event

(Note 1)

Comments

TP1 1.45m No calculation N/A Further testingrequired in thislocality

TP2 1.40m 2.59 x 10-6 m/sec 1.88m x 1.99m (L x W) x1.05m effective depthHalf empty time – 15 hours

Cubiform chamber willsuit ground conditions

TP3 1.80m 4.23 x 10-7 m/sec 15.81m x 0.24m (L x W) x1.05m effective depthHalf empty time – 23 hours

Long narrow pitrequired to dischargewaters effectively.Cubiform chamberunacceptable

Notes:1. BRE 365 Soakaway Design methodology, based on drainage through soakaway sides only (effective

depth) with a factor of safety of 1 is applied as it assumes the base may silt up with time, granularbackfill porosity with 30% free volume design aims for a soakaway to be les than half full in 24hours following a storm event based on M5 - 60 minutes rainfall and 60 minutes rainfall duration

2. No allowance has been made for possible climate change effects. It may be necessary to include anallowance of +20% to the peak rainfall intensity for design storm events.

Hannah-Reed Permeability testing -Land west of Carterton,

28 February 2011 Report No. S.3909 Oxfordshire

Martyn Paul Boughton BSc (Hons) Julian M Huxham BSc (Hons)FGS

Page 3

Of course, the indicative infiltration drainage design is for illustrative purposes only,a more specific design based on the actual land area available and various stormduration permutations should be considered. It should be noted these calculatedvalues have been based on a software programme produced from the official BREDigest 365 Soakaway Design.

It should be noted that the (f) values were extrapolated on the basis of a single setof results for TP3 and two sets of results for TP2 and not the standard three sets.Therefore the results do not necessarily reflect natural working conditions wherebythe soil has previously been saturated. The designer should therefore take this intoconsideration when designing the soakaway chambers.

The indicative infiltration drainage design shows that infiltration drainage couldform a component of the drainage strategy for the development of the site. Theunderlying rock layer, which was not penetrated should be further exploited withadditional testing to confirm its effectiveness as a drainage medium which weanticipate may yield higher permeability potential. We recommend addition testingis conducted over a more intensive area at greater depths and within a relatively dryperiod to avoid surface waters entering the test pits.

Permissions to drain into the ground should be sought from the EnvironmentAgency given the site overlies a Secondary (A) Aquifer. It is anticipated acceptancewill be granted for provision of discharge of all roof drainage without demurral buthardstanding drainage will require installation of interceptors. It is likely that adepth limit will be imposed on the level of the soakaway chambers.

Should you have any queries regarding the above, please do not hesitate to contactthe undersigned.

For and on behalf ofGround Investigation ServicesYours sincerely

Martyn Boughton (Partner)

Email: [email protected]

Enc Site Plan and Infiltration Test Results

Trial Pit position (infiltration Test)

Land west of Carterton, Oxfordshire

Fig

1

Ground Investigation Report No.

Services S.3909TRIAL PIT LOCATION PLAN

Date: February 2011 Fax 01235 553972

CLIENT: Hannah-Reed Ground Investigation Services

15 Bostock Road

SITE: Abingdon OX14 1DP

Tel 01235 521631

Five

TP1

TP2

TP3

Depth (m)

Brown clayey sand

TOPSOIL

Soft orange brown sandy CLAY

Medium dense rubbly LIMESTONE brash with some to much interbedded

orange brown sandy clay

Firm light grey mottled orange brown CLAY with some to much fine gravel sized

limestone fragments and a little sand pockets

Weak to moderately strong thinly bedded LIMESTONE rock with a little interbedded

orange brown clayey sand

FOREST MARBLE

Test Pit Dimensions: 1.40 x 0.55 x 1.45m (Length x width x depth - metres)

Date of Testing: Logged by: MPB

Checked by: JMH

SOAKAGE TEST DATA

Elapsed

time in

Minutes Test 1 Test 2 Test 3#

0 0.51

30 0.51

60 0.51

90 0.51

120 0.505

180 0.505

240 0.50

300 0.495

360 0.49

1410 0.44

1590 0.44

1770 0.44

2850 0.44

3030 0.44

REMARKS: It was not possible to complete testing in accordance with BRE Standards due to rising

water levels as a result of perched groundwater entering the pit

# Tests 2 and 3 not undertaken

CLIENT: Hannah-Reed BRE DIGEST 365 : 1991

SITE : SOAKAWAY DESIGN

Date: February 2011

TEST PIT DATA TRIAL PIT NO. 1

Strata Description

GL

0.60

1.30

0.20

0.90

Weather: Mild, dry and bright

Depth to Water (metres)

#

14-16 February 2011

Groundwater strike: 0.60m (seepage)

Groundwater standing:

Fig.Services

15 Bostock Road, Abingdon OX14 1DP S.3909 2Tel 01235 521631 Fax 01235 553972

INSUFFICIENT DATA TO CALCULATE


Ground Investigation

PERMEABILITY TESTReport No.

SOIL INFILTRATION RATE, f

Depth (m)

Brown clayey sand with some limestone fragments

TOPSOIL

Medium dense rubbly LIMESTONE brash with some to much interbedded orange brown

sandy clay

Firm light grey mottled orange brown CLAY with some fine gravel sized

limestone fragments

Moderately strong LIMESTONE rock

FOREST MARBLE



Checked by: JMH

SOAKAGE TEST DATA

Elapsed

time in


0 0.60 0.43

30 0.65 0.48

60 0.69 0.53

90 0.73 0.56

120 0.77 0.60

180 0.83 0.66

240 0.88 0.71

300 0.92 0.75

360 0.79

400 0.83

1140© 1.40©

1350@ 1.40@

1410 1.26

1530 1.29

2101© 1.40©

REMARKS: © Interpolated time when dry

@ Actual time when dry

# Test 3 not undertaken due to limited time constraints

* Soil infiltration rate based on extrapolated data

Test 2 used to calculate infiltration rate



Date: February 2011


2.59 x 10-6 m/sec *



PERMEABILITY TESTReport No. Fig.

Services15 Bostock Road, Abingdon OX14 1DP S.3909 3Tel 01235 521631 Fax 01235 553972

Groundwater standing: Dry Weather: Mild, dry and bright


1.15

1.40

14-16 February 2011

Groundwater strike: Dry

0.35


Strata Description

GL

Depth (m)

Brown clayey sand with some limestone fragments

TOPSOIL

Soft to firm orange brown sandy CLAY with some fine to medium gravel sized

limestone fragments

Medium dense rubbly LIMESTONE brash with some to much interbedded orange brown

sandy clay

Moderately strong LIMESTONE rock

FOREST MARBLE



Checked by: JMH

SOAKAGE TEST DATA

Elapsed

time in


0 0.53

30 0.57

60 0.63

90 0.66

120 0.70

180 0.75

240 0.80

1290 1.05

1470 1.06

1650 1.07

2730 1.13

2910 1.14

12105© 1.80©

REMARKS: © Interpolated time when dry

# Test 2 and 3 not undertaken due to limited time constraints

* Soil infiltration rate based on extrapolated data

Test 1 used to calculate infiltration rate



Date: February 2011

Fig.Services

15 Bostock Road, Abingdon OX14 1DP S.3909 4Tel 01235 521631 Fax 01235 553972


4.23 x 10-7 m/sec *



PERMEABILITY TESTReport No.

14-16 February 2011

Groundwater strike: Dry

Groundwater standing: Dry Weather: Mild, dry and bright


#

1.80


Strata Description

GL

0.35

0.85

x210165 foul drainage options report rev a march...

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