Flood Risk Assessment for Priddy's Yard, Water End, Old Basing, Basingstoke, Hampshire, RG24

Flood Risk Assessment

For

Priddy’s Yard, Water End, Old Basing, Basingstoke, Hampshire, RG24 7BA

Project No. RRL036 1

Flood Risk Assessment

for

Priddy’s Yard, Water End, Old Basing, Basingstoke, Hampshire, RG24 7BA

Client: Hackwood Homes Ltd 6 Hackwood Business Park Water End, Basingstoke, Hampshire RG24 7BA

ISSUE A B Issued By S Ho S Ho

Date June 2018 June 2018 Purpose Planning Planning

Approved By CH CH

Project No: RRL034

The Town House, St.George’s Square, Bishops Waltham, Southampton, Hampshire, SO32 1AF E: [email protected] W: www.archassociates.co.uk T: 01489 890004 F: 01489 890005

Directors: Allen Rushby IEng, MIStructE. Chris Hendry MSc, CEng, MIStructE Associates: Daniel Waddup BEng [Hons], CEng, MIStructE. Jason Bentley Arch Associates Limited. Registered in England: 3832290 CONTENTS

1.0 Introduction

2.0 Evidence Base

3.0 Site Details

4.0 Flood Risk Policies and Guidance

5.0 Sources of Flood Risk

6.0 Proposed Surface Water Drainage Strategy

7.0 Proposed Foul Water Drainage Strategy

8.0 Conclusion and Recommendation

Figure 1 Site Location Plan Appendix 1 Proposed Masterplan Appendix 2 Topography Survey Appendix 3 British Geological Survey Online Mapping and Historical Borehole Log Appendix 4 EA’s Product 4 Data Appendix 5 Extracts of Natural England’s MAGIC Appendix 6 Extracts of Basingstoke and Deane Borough Council’s SFRA Appendix 7 Foul Water Drainage Calculation

Project No. RRL034 3 Background Information

Arch Associates have been commissioned by Hackwood Homes Ltd to undertake a Flood Risk Assessment to accompany the full planning application submission for an existing development extension scheme on a land south of London Road (A30), Old Basing, Basingstoke, Hampshire.

The existing development is a 2-storey office block (Use Class B1). Under the new proposal, the existing office block will be extended longitudinally by approximately 10m southwards to increase office floor spaces. This proposal will have no impact to the existing access road and the associated infrastructures.

The foul water drainage run-off generated from the proposed building extension will be increased by a negligible amount, and therefore will have minimal impact to the existing on-site private foul drainage network. Therefore, it is anticipated that no reinforcement work will be necessary for this site. However, any alterations in drainage flows to the Thames Water sewers will have to be agreed with Thames Water under the Water Industry Act (WIA) Section 106 Agreement. The foul water drainage requirement is discussed in detail in Section 3.1.

The surface water run-off generated from the post-development will remain unchanged as current, as the existing area to be replaced by the building extension is already a hardstanding area. Therefore, it is anticipated that no reinforcement work will be necessary for this site. Any connection to the private sewer will have to be agreed with the landowners and other concerned parties. The proposed surface water strategy is discussed in more detail in Section 3.2 of this report.

This report has been issued in accordance with the Basingstoke and Deane Borough Council’s Strategic Flood Risk Assessment, which provides the local plan evidence base necessary for applying the planning permission application.

Project No. RRL034 4 1.0 Introduction

The purpose of this report is to review the current risks of flooding and the impact of the development proposals to the site and elsewhere within the vicinity area from all sources, based on the desktop study and modelled data where known, to ensure that the Flood Risk Assessment used to gain the planning consent still representative. This report has been prepared in accordance with the National Planning Policy Framework (NPPF) (March 2012), the Planning Practice Guidance (PPG) (Nov 2016), Non-Statutory Technical Standards for Sustainable Drainage System (March 2015) and EA Guidance.

2.0 Evidence Base

2.1 Basingstoke and Deane Borough Council’s Strategic Flood Risk Assessment The Strategic Flood Risk Assessment (SFRA) for the site were obtained from Basingstoke and Deane Borough Council (BDBC)’s web site and are presented in Appendix 6.

2.2 UK Government’s Flood Warning Information Services Online Mapping The Flood Warning Information Services Online Mapping was accessed via the UK Government’s website to review detailed mapping information where appropriate and relevant printouts of flood maps are presented in Section 5.

2.3 Natural England’s MAGIC Natural England’s MAGIC information website is presented in Appendix 5.

2.4 EA’s Product 4 Flood Mapping Ea’s Product 4 Flood Mapping was received on 25th May 2018 and is included in Appendix 4.

2.5 British Geological Survey British Geological Survey (BGS) online mapping and historical borehole log are presented in Appendix 3.

2.6 360 Geomatics’s Topography Survey 360Geomatics’s topography survey dated May 2018 is presented in Appendix 2.

Project No. RRL034 5 3.0 Site Details

3.1 Site Location and Description The brownfield site is located at a land to the south of London Road (A30), Old Basing, Basingstoke, Hampshire. The site is bounded to the north by the dual- carriageway London Road (A30) and the Christopher Plumbing Services commercial properties, to the west and south by a large pasture land, and to the east by the Andwell Lane and a main watercourse Lyde River. A copy of the proposed masterplan is presented in Appendix 1.

The main watercourse, Lyde River, located immediately to the east of the site, flows from south to north in direction. Lyde River is a tributary of River Loddon adjoined at approximately 4.28km to the north in Sherfield on Loddon. Further to the north-east at 26.95km, River Loddon is adjoined with River Thames in Reading.

The existing vehicle access to the site is gained via the west-bound of London Road (A30), and it will not be impacted by the development proposals.

3.2 Existing Site Topography and Drainage 360Geomatics’s topography survey indicates that the site is generally flat. The highest ground level recorded is 65.864m AOD to the south of the existing building in the south-eastern corner of the site, and the lowest ground level is 65.140m AOD adjacent to north of the building in the north-eastern corner of the site. The topography survey drawing is included in Appendix 2.

Since the development is a brownfield site, it is anticipated that the private drainage networks are presented across the site.

Project No. RRL034 6 3.3 Geology BGS online mapping indicates that the bedrock beneath the site is the London Clay Formation which comprises Clay, Silt and Sand. BGS mapping also indicates that the superficial deposits across the majority of the site is designated as Alluvium which comprises Clay, Silt, Sand and Gravel; whilst a small portion of the area in the south is designated as River Terrace Deposits (Undifferentiated) which comprises Sand and Gravel. The BGS’s geology mapping is presented in Appendix 3.

BGS’s historical borehole log undertaken at approximately 240m to the south-west of the site indicates that the made ground is underlain by approximately 0.6m thick Alluvium of brown-silty Clay over 2.0m thick River Terrace of Clayey gravel. Further below at the bedrock stratum is the London Clay of grey-silty Clay 0.5m thick whereby the borehole was completed. The BGS’s historical borehole log is presented in Appendix 3.

Project No. RRL034 7 4.0 Flood Risk Policies and Guidance

These documents set out the requirements for flood risk management and detail the criteria for the content of an FRA report. The requirements of these documents are detailed below:

National Planning Policy Framework 2012

4.1 The NPPF published by the Department for Communities and Local Government in March 2012 sets out the Government’s planning policy for England and how these should be applied. The PPG was published in November 2016 as an online document to provide the technical guidance to the NPPF.

The aim of the NPPF in term of climate change is to steer new developments to areas less vulnerable to the range of impacts arising from climate change.

In accordance with footnote 5 under the NPPF, a site-specific flood risk assessment is required for:

• Proposals of 1 hectare or greater in Flood Zone 1;

• All proposals for new development in Flood Zones 2 and 3,

• An area within Flood Zone 1 which has critical drainage problems,

• Proposed development or change of use to a more vulnerable class may be subject to other sources of flooding.

4.2 Table 1: Flood Zones under the PPG defines the EA Flood Zones as follows:-

Flood Zone 1 Low Probability – Defined as land assessed as having less than 1 in 1,0000 annual probability of river of sea flooding (<0.1%).

Flood Zone 2 Medium Probability – Defined as land assessed as having between 1 in 100 and 1 in 1,000 annual probability of river flooding (1% - 0.1%) or between 1 in 200 and 1 in 1,000 annual probability of sea flooding (0.5% - 0.1%).

Flood Zone 3a High Probability – Defined as land assessed as having a 1 in 100 or greater annual probability of river flooding; or Land having a 1 in 200 or greater annual probability of sea flooding.(Land shown in dark blue on the Flood Map);

Flood Zone 3b The Functional Floodplain – Defined as land where water has to flow or be stored in times of flood (as identified by LPAs in their SFRA in agreement with the EA).

Project No. RRL034 8 4.3 Table 2: Flood Risk Vulnerability Classification under the PPG defines the flood risk vulnerability classes as follows:

Essential infrastructure • Essential transport infrastructure (including mass evacuation routes) which has to cross the area at risk. • Essential utility infrastructure which has to be located in a flood risk area for operational reasons, including electricity generating power stations and grid and primary substations; and water treatment works that need to remain operational in times of flood. • Wind turbines.

Highly vulnerable • Police stations, ambulance stations and fire stations and command centres and telecommunications installations required to be operational during flooding. • Emergency dispersal points. • Basement dwellings. • Caravans, mobile homes and park homes intended for permanent residential uses. • Installations requiring hazardous substances consent. (Where there is a demonstrable need to locate such installations for bulk storage of materials with port or other similar facilities, or such installations with energy infrastructure or carbon capture and storage installations, that require coastal or water-side locations, or need to be located in other high flood risk areas, in these instances the facilities should be classified as “essential infrastructure”).

More vulnerable • Hospitals. • Residential institutions such as residential care homes, children’s homes, social services homes, prisons and hostels. • Buildings used for dwelling houses, student halls of residence, drinking establishments, nightclubs and hotels. • Non–residential uses for health services, nurseries and educational establishments. • Landfill and sites used for waste management facilities for hazardous waste. • Sites used for holiday or short-let caravans and camping, subject to a specific warning and evacuation plan. 7

Less vulnerable • Police, ambulance and fire stations which are not required to be operational during flooding. • Buildings used for shops, financial, professional and other services, restaurants and cafes, hot food takeaways, offices, general industry, storage and distribution, non– residential institutions not included in “more vulnerable”, and assembly and leisure. • Land and buildings used for agriculture and forestry. • Waste treatment (except landfill and hazardous waste facilities). • Minerals working and processing (except for sand and gravel working). • Water treatment works which do not need to remain operational during times of flood.

Project No. RRL034 9 • Sewage treatment works (if adequate measures to control pollution and manage sewage during flooding events are in place).

Water-compatible development • Flood control infrastructure. • Water transmission infrastructure and pumping stations. • Sewage transmission infrastructure and pumping stations. • Sand and gravel working. • Docks, marinas and wharves. • Navigation facilities. • Ministry of Defence defence installations. • Ship building, repairing and dismantling, dockside fish processing and refrigeration and compatible activities requiring a waterside location. • Water-based recreation (excluding sleeping accommodation). • Lifeguard and coastguard stations. • Amenity open space, nature conservation and biodiversity, outdoor sports and recreation and essential facilities such as changing rooms. • Essential ancillary sleeping or residential accommodation for staff required by uses in this category, subject to a specific warning and evacuation plan.

4.4 Table 3: Flood risk vulnerability and flood zone ‘compatibility’ under the PPG as below:

Project No. RRL034 10 4.5 Environment Agency Guidelines

In addition to the NPPF the EA has produced Standing Advice and Guidance on development and FRAs which aim to outline the requirements for a FRA according to the nature of the development and the site location in relation to the Flood Zones. The following extract from the EA guidance sets out these FRA requirements.

When you need an assessment

In accordance with Section 2.2 under the EA’s Improving the Flood Performance of New Buildings (May 2007), a site-specific flood risk assessment is required to support a planning application for sites:

• more than 1 hectare (ha) in flood zone 1 • in flood zone 2 or 3 including minor development and change of use • less than 1 ha in flood zone 1, including a change of use in development type to a more vulnerable class (e.g. from commercial to residential), where they could be affected by sources of flooding other than rivers and the sea (eg, surface water drains, reservoirs) • in an area within flood zone 1 which has critical drainage problems as notified by the Environment Agency

When you don’t need an assessment

You don’t need to do a flood risk assessment for a development that’s less than 1 ha in flood zone 1 unless it could be affected by sources of flooding other than rivers and the sea, e.g. surface water drains.

When to follow standing advice

You should follow the Environment Agency’s standing advice if you’re carrying out a flood risk assessment of a development classed as: • a minor extension (household extensions or non-domestic extensions less than 250 square metres) in flood zone 2 or 3 • ‘more vulnerable’ in flood zone 2 (except for landfill or waste facility sites, caravan or camping sites) • ‘less vulnerable’ in flood zone 2 (except for agriculture and forestry, waste treatment, mineral processing, and water and sewage treatment) • ‘water compatible’ in flood zone 2 You also need to follow standing advice for developments involving a change of use into one of these vulnerable categories or into the water compatible category.

Project No. RRL034 11 5.0 Sources of Flood Risk

In accordance with the NPPF requirement, all sources of flooding must be considered within the site-specific FRA. A review of BDBC’s SFRA, UK Government’s Flood Warning Information Services Online Mapping, Natural England’s MAGIC information website and EA’s Product 4 data have been completed, and the sources of flood risk identified in the vicinity area are summarised in the following:

5.1 Flood Risk from River (Fluvial)

EA’s Product 4 flood map confirms that the site lies within Flood Zone 3a, which is considered to be a very high risk of flooding from the adjacent watercourse, Lyde River. A copy of the EA’s Product 4 is presented in Appendix 4.

This is further proven by UK Government’s Flood Warning Information Services Online Mapping, which also indicates the site to be located within the high Flood risk area. The UK Government’s Flood Warning Information Services Online Mapping is presented below.

In accordance with the National Planning Policy Framework (NFFP) as described in Section 4 of this report, the proposed development with use class B1 (office) is considered to be less vulnerable, which is appropriate for development within Flood Zone 3a subject to passing the Sequential Test by designing flood resilience development. As such the development will meet the philosophy of the Sequential Test and no application of the Exception Test will be required, therefore satisfying the NPPF.

Project No. RRL034 12 5.2 Flood Risk from Groundwater

Natural England’s MAGIC website indicates that the site is not located within the Groundwater Source Protection Zone (SPZ). However, the site is located within proximity of the Groundwater Vulnerability Zones designated as Minor Aquifer Intermediate. The bedrock and the superficial deposits beneath portions of the site are designated as Secondary A Aquifers. The MAGIC’s groundwater maps are presented in Appendix 5.

BGS’s historical borehole log indicates that groundwater was encountered at approximately 1m below ground, which is considered to be shallow depth. Given the high groundwater table, it is anticipated that the soakaway drainage technique may not be suitable for this site. The BGS’s historical borehole log is presented in Appendix 3.

5.3 Flood Risk from Surface Water

UK Government Flood Warning Information Services and BDBC’s SFRA mapping indicate that the site is subject to low to high risks of surface water flooding within the site. Extracts of BDBC’s SFRA is presented in Appendix 6.

The Flood Warning Information Services’ online mapping is presented below:

However, EA’s Product 4 data advises that the site is subject to very low risk of flooding from surface water. A copy of the EA’s Product 4 is presented in Appendix 4.

Project No. RRL034 13 5.4 Historical Flooding Records

EA’s Product 4 data advises that the site is located outside the historical flood events occurred in 1947, which is extended adjacent to the southern boundary of the site.

5.5 Flood Risk from Reservoir

UK Government Flood Warning Information Services’ online mapping indicates that Old Basing lies outside the extents of flood risk from reservoirs, and therefore the site is considered to be at very low risk from reservoir flooding.

Project No. RRL034 14 6.0 Proposed Surface Water Drainage Strategy The existing development rooftop area is 590.10m2, and the post-development rooftop area will be increased by circa 35% to 794.65m2.

Any connection to the private sewer will have to be agreed with the landowners and other concerned parties.

Overland/surface exceedance flows due to extreme events or blockage of drainage systems would naturally flow towards the north of the site onto London Road (A30) and runoff in westerly direction.

7.0 Proposed Foul Water Drainage Strategy

Any connection to the private sewer will have to be agreed with the landowners and other concerned parties. Any alterations in drainage flows to the Thames Water sewers will have to be agreed with Thames Water under the Water Industry Act (WIA) Section 106 Agreement.

The hydraulic design for the discharge rate for the foul wastewater design has been calculated in accordance with Thames Water produced Daily Peak Discharge Flow Rates Schedule for various types of building usage, which state the design flow rates of 4950l/100m2/day for office premises. Therefore, the discharge rate for the proposed development extension equates to a peak foul discharge rate of approximately 0.46 l/s. Refer to Appendix 7 for the foul water drainage calculation.

Project No. RRL034 15 8.0 Conclusions and Recommendation

The site lies within the Environment Agency’s Flood Zone 3a, and is considered to be at very high risk of flooding from the adjacent watercourse, Lyde River.

In accordance with the National Planning Policy Framework, the proposed development with use class B1 (office) is considered to be less vulnerable, which is appropriate for development within Flood Zone 3a subject to passing the Sequential Test by designing flood resilience development. As such the development will meet the philosophy of the Sequential Test and no application of the Exception Test will be required, therefore satisfying the NPPF.

The site is subject to very low risk of flooding from surface water within the site in accordance with the EA’s Product 4 data.

The site is not subject to the historical flood event occurred in 1947 in accordance with EA’s Product 4 data.

The groundwater table is approximately 1.0m below ground level within the vicinity area, and therefore soakaway drainage technique may not be suitable for this site.

The existing development rooftop area is 590.10m2, and the post-development rooftop area will be increased by circa 35% to 794.65m2.

Overland/surface exceedance flows due to extreme events or blockage of drainage systems would naturally flow towards the north of the site onto London Road (A30) and runoff in westerly direction.

The foul water drainage run-off generated from the proposed building extension will be increased by a negligible amount to 0.46 l/s, and therefore will have minimal impact to the existing on-site private foul drainage network. Therefore, it is anticipated that no reinforcement work will be necessary for this site.

This FRA report has been undertaken in full compliant with the requirements of NPPF. The report has demonstrated that the development site does not have issues relating to flood risk and drainage, and that the proposals will not cause any adverse effects to the site as well as the vicinity area.

Steven Ho BEng (Hons), Graduate Member of ICE For and on behalf of Arch Associates

Project No. RRL034 16

FIGURE 1

Site Location Plan

Project No. RRL034 client: title: HACKWOOD HACKWOOD GROUP LOCATION PLAN address: withoutpermission Ordnanceofthe prior Survey Reproductionwholein prohibitedin is or part Ordnance100048957licenceSurvey Crowncopyright right database2018 and Serial number: 135779 Ukmapcentre.com Ordnance Survey 152988 153000 153100 153200 153238

RG24 7BARG24 BASINGOLD ENDWATER HACKWOODBUSINESS PK

469179 469179

r a i n

469200 469200 Mile StoneMile

Tollgate

3 10 Depot The Y KnotInn Y The (PH) Priddys YardPriddys

n d

469300 metres 469300 20 30

2 50 5

Lyde HouseLyde Cottage

6 5 LB Unit 1

469400 469400

0 4

drwg. no: drwg. no: scale: date:

469429 469429 LP/1718/08 152988 153100 153000 153200 153238 1:1250 1:1250 @ A3 MARCH MARCH 2018 JSL JSL [email protected] JSL ARCHITECTURALLTDSERVICES JSL SOUTH SOUTH WONSTON ROAD DOWNS 51A 01962 808221 07732 322410 01962 808221 WINCHESTER SO21 3EW WINCHESTER SO21

APPENDIX 1

Proposed Masterplan

Project No. RRL034 PROFILE CLADDING

PROFILE CLADDING BRICKWORK PROFILE CLADDING

EXISTING FRONT ELEVATION 1:100 @ A1 EXISTING SIDE ELEVATION

PROFILE CLADDING

EXISTING REAR ELEVATION EXISTING SIDE ELEVATION

PROFILE CLADDING

BRICKWORK

PROPOSED FRONT ELEVATION 1:100 @ A1 PROPOSED SIDE ELEVATION

title : ELEVATIONS MAIN OFFICE

client: THE HACKWOOD GROUP

address: HACKWOOD BUSINESS PARK WATER END OLD BASING PROFILE CLADDING RG24 7BA

date: MARCH 2018

scale: 1:100 @ A1 PROPOSED REAR ELEVATION PROPOSED SIDE ELEVATION

drwg. no: EL/1718/06

JSL ARCHITECTURAL SERVICES LTD 51A DOWNS ROAD SOUTH WONSTON WINCHESTER SO21 3EW 01962 808221 07732 322410 JSL [email protected] LEGAIS SPARE ROX INTERIOR DESIGN STUDIO PAUL WILLIAMS OFFICE CHRIS GODDARD

Mains operated smoke detectors to BS 5839 part 1 Part B External wall more than 1000mm from the Part B1 boundary. Permitted unprotected area (window Vision panels to be installed on all doors to MEETING ROOM openings) is 8% of total unprotected area. Total inner room to warn occupants of fire. Small area of windows 6.3% of unprotected area (if premises - so shouted warning sufficient. 1050mm deep; 7.2% if 1200mm deep).

FD30S fire rated door

OPEN OFFICE OPEN OFFICE

GLENN COATS

BOARDROOM TEA STATION OFFICE

STORE

PROPOSED FIRST FLOOR PLAN 1:100

ORESTONES OFFICE OFFICE OFFICE

10135.00

1050.00

EXIT SVP EXIT SVP EXIT

CLEANERS STORE MAINS/ IT ROOM STORE/WC

COFFEE LOUNGE

Part B1 Vision panels to be installed on all doors to SVP SVP STATIONERY inner room to warn occupants of fire. Small ARCHIVE premises - so shouted warning sufficient.

Where internal glazed areas are part of a door FD30S fire or within 300mm to the side of a door, they are DISABLED rated door to consist of safety glazing where within WC 1500mm of floor level. Part K4 FEMALE WC MALE WC

Mains operated smoke Mains operated smoke detectors to BS 5839 part 1 detectors to BS 5839 part 1 Mechanical extractor at ventilation rateo ofWC, 6ltrs t Mains operated smoke with 15min. overrun installed in accordance with FD30S fire detectors to BS 5839 part 1 manufacturer instructions to comply with AD Part F rated door STORES Mains operated smoke FD30S fire detectors to BS 5839 part 1 FD30S fire rated door rated door STORE

PORTAL FRAME GRID

RECEPTION STORES Mains operated smoke detectors to BS 5839 part 1

EXIT

COFFEE ROLLER SHUTTER DOOR ROLLER SHUTTER DOOR title : FLOOR PLANS: EXTENSION

Inspection chamber client: THE HACKWOOD GROUP

OVERHANG ORESTONES OFFICE address: HACKWOOD OFFICES WATER END OLD BASING ROLLER SHUTTER DOOR ROLLER SHUTTER DOOR RG24 7BA

date: FEBRUARY 2018

PROPOSED GROUND FLOOR PLAN 1:100 scale: 1:100 @ A1

drwg. no: FPE/1718/05

JSL ARCHITECTURAL SERVICES LTD 51A DOWNS ROAD SOUTH WONSTON WINCHESTER SO21 3EW JSL 01962 808221 07732 322410 [email protected]

APPENDIX 2

Topography Survey

Project No. RRL034 Coordinate Table

Station Eastings Northings Level Description

Scale bar 0 2 4 6 8 10 12 14 16 18 20m 1:200 20m

Note 12

0 C

1:200 Abbreviations (Where Applicable)

Fence Types

Legend

Rev Suffix Revision Details Initial Date

Surveyed by

10 Salters Heath Road Monk Sherborne, Tadley Hampshire RG26 5HY Tel: 01256 851672 Mob: 07734 233459 Email: [email protected] Website: www.360g.co.uk

Client:

6 Hackwood Business Park, Water End Basingstoke, Hampshire, RG24 7BA

Job Title: SURVEY AT HACKWOOD BUSINESS PARK WATER END BASINGSTOKE

Drawing Title: LEVEL SURVEY

Drawing No: Rev Suffix: 360G/18032T/100

Drawn: Checked: Scale: Date: PB JM 1:200 MAY 2018

Job No: Sheet: Sheet Size: 360G-18032T 1 of 1 A1

APPENDIX 3

British Geological Survey Online Mapping and Historical Borehole Log

Project No. RRL034 RRL034 – Hackwood Office, Priddy’s Yard, Old Basing, Basingstoke, Hampshire British Geological Survey Mapping – Bedrock Deposit

AAL055 – Blacknest Road, Blacknest, Alton, Hampshire British Geological Survey Mapping – Superficial Deposit

BGS ID: 422197 : BGS Reference: SU65SE95 British National Grid (27700) : 469140,152890 Report an issue with this borehole

<< < Prev Page 1 of 1  Next > >>

http://scans.bgs.ac.uk/sobi_scans/boreholes/422197/images/10756221.html 14/ 06/ 2018

APPENDIX 4

EA’s Product 4 Data

Project No. RRL034 Flood Map for Planning centred on Hackwood Business Park, Basingstoke, RG24 7BA Created on 25/05/18 REF: THM86926

Kilometres 0 0.25 0.5

Legend

Main River Flood defences Areas benefiting from flood defences Flooding from rivers or sea (FZ3) Extent of extreme flood (FZ2) Flood Map - flood storage areas

Flooding from rivers or sea without defences (Flood Zone 3) shows the area that could be affected by flooding: - from the sea with a 1 in 200 or greater chance of happening each year - or from a river with a 1 in 100 or greater chance of happening each year.

The Extent of an extreme flood (Flood Zone 2) shows the extent of an extreme flood from rivers or the sea with up to a 1 in 1000 chance of occurring each year.

© Environment Agency copyright and / or database rights 2015. All rights reserved. © Crown Copyright and database right. All rights reserved. Environment Agency, 100024198, 2015. Contact Us: National Customer Contact Centre, PO Box 544, Rotherham, S60 1BY. Tel: 08708 506 506 (Mon-Fri 8-6). Email: [email protected] Risk of flooding from Surface Water Centred on RG24 7BA Created 25/05/18 THM86926

Scale 1: 10,000

Likelihood of flooding from Surface Water

Very Low

Likelihood of flooding from Surface Water

High: Greater than or equal to 3.3% (1 in 30) chance in any given year Medium: Less than 3.3% (1 in 30) but greater than or equal to 1% (1 in 100) chance in any given year Low: Less than 1% (1 in 100) but greater than or equal to 0.1% (1 in 1,000) chance in any given year Very Low: Less than 0.1% (1 in 1,000) chance in any given year

This information is shown on the Risk of Flooding from Surface Water map on our website.

Contact Us: National Customer Contact Centre, PO Box 544, Rotherham, S60 1BY. Tel: 03708 506 506 (Mon-Fri 8-6). E-mail: [email protected] Historic Flood Map centred on Hackwood Business Park, Basingstoke, RG24 7BA Created on 25/05/18 REF: THM86926

Kilometres 0 0.25 0.5

Legend

Main River year 1947

The Extent of an extreme flood (Flood Zone 2) shows the extent of an extreme flood from rivers or the sea with up to a 1 in 1000 chance of occurring each year.

APPENDIX 5

Extracts of Natural England’s MAGIC

Project No. RRL034 MAGIC Source Protection Zones

Legend Source Protection Zones merged (England) Zone I - Inner Protection Zone

Zone I - Subsurface Activity

Zone II - Outer Protection Zone

Zone II - Subsurface Activity

Zone III - Total Catchment

Zone III - Subsurface Activity

Zone of Special Interest

0 1 2

Projection = OSGB36

xmin = 449500 0 1.5 3 ymin = 144800

xmax = 490200 km ymax = 164600 Map produced by MAGIC on 14 June, 2018. Copyright resides with the data suppliers and the map must not be reproduced without their permission. Some information in MAGIC is a snapshot of the information (c) Crown Copyright and database rights 2018. Ordnance Survey 100022861. that is being maintained or continually updated by the originating organisation. Please refer to the metadata for details as information may be illustrative or representative rather than definitive at this stage. MAGIC Groundwater Vulnerability Map

Legend Groundwater Vulnerability Map (England) Major Aquifer High

Major Aquifer Intermediate

Major Aquifer Low

Minor Aquifer High

Minor Aquifer Intermediate

Minor Aquifer Low

0 1 2

Projection = OSGB36

xmin = 449500 0 1.5 3 ymin = 144800

Legend Aquifer Designation Map (Bedrock) (England) Principal

Secondary A

Secondary B

Secondary (undifferentiated)

Unproductive

0 1 2

Projection = OSGB36

xmin = 449500 0 1.5 3 ymin = 144800

Legend Aquifer Designation Map (Superficial Drift) (England) Principal

Secondary A

Secondary B

Secondary (undifferentiated)

Unknown (lakes+landslip)

Unproductive

0 1 2

Projection = OSGB36

xmin = 449500 0 1.5 3 ymin = 144800

APPENDIX 6

Extracts of Basingstoke and Deane Borough Council’s SFRA

Project No. RRL034 Strategic Flood Risk Assessment Update May 2012 Basingstoke and Deane Potential Risk from Watercourses - Area 6 Refer to area location plan for key

(! (! (! ± (!

(! (! (!

(! (!

This map is reproduced from Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery Office © Crown copyright. Unauthorised reproduction infringes Crown copyright 0 550 1,100 2,200 3,300 4,400 and may lead to prosecution or civil proceedings. HCC 100019180 2010 Meters Strategic Flood Risk Assessment Update May 2012 Basingstoke and Deane Potential Surface Water Flood Risk (1:30) - Area 6 Refer to area location plan for key and notes ±

This map is reproduced from Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery This map gives an indication of the broad areas likely to be at risk of surface Office © Crown copyright. Unauthorised reproduction infringes Crown copyright water flooding. It is not suitable for use at an individual property scale 0 550 1,100 2,200 3,300 4,400 and may lead to prosecution or civil proceedings. HCC 100019180 2010 due to the method used Meters Strategic Flood Risk Assessment Update May 2012 Basingstoke and Deane Potential Surface Water Flood Risk (1:200) - Area 6 Refer to area location plan for key and notes ±

This map is reproduced from Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery This map gives an indication of the broad areas likely to be at risk of surface Office © Crown copyright. Unauthorised reproduction infringes Crown copyright water flooding. It is not suitable for use at an individual property scale 0 550 1,100 2,200 3,300 4,400 and may lead to prosecution or civil proceedings. HCC 100019180 2010 due to the method used Meters Strategic Flood Risk Assessment Update May 2012 Basingstoke and Deane Historic Flooding - Area 6 Refer to area location plan for key ±

1:30 Flood notes:

The SW_30_300 relates to the approximate extent of flooding under a 1:30 year storm scenario with depths in excess of 300mm.

The SW_30_100 relates to the approximate extent of flooding under a 1:30 year storm scenario with depths in excess of 100mm.

1:200 Flood notes:

The SW_200_300 relates to the approximate extent of flooding under a 1:200 year storm scenario with depths in excess of 300mm.

The SW_200_100 relates to the approximate extent of flooding under a 1:200 year storm scenario with depths in excess of 100mm.

General Keys

1:30 Flood Key: 1:200 Flood Key:

Legend Legend

EA Main River Line EA Main River Line Detailed River Network - Centrelines Detailed River Network - Centrelines SW_30_300 SW_200_300 SW_30_100 SW_200_100

Potential Risk from Watercourses Key: Historic Flood Risk Key:

Legend Legend

!( Monitoring Network GW Flooding-Southern Water Artificial Waterbodies: Canals Southern Water Sewer Incidents Point

River Waterbody Catchments EA GW Flooding-TW EA Main River Line GW flooding-Southern Water

Basingstoke Flood Defence Localised Flooding Basingstoke Canal EA GW Flooding-Southern Water

EA Flood Zone 2 Critical Drainage Areas

EA Flood Zone 3 Upstream of Critical Drainage Areas EA Flood Warning Areas (Oct 2011) TW Sewer Incidents Area

Detailed River Network HCC Recorded Flooding

Acronyms:

EA – Environment Agency SW – Surface Water GW – Ground Water TW – Thames Water HCC – Hampshire County Council

APPENDIX 7

Foul Water Drainage Calculation

Project No. RRL034 Foul Water Design Flows

Daily Design / DWF Peak Flow No. of Units Q l/s (l/day) (l)

General Housing per dwelling (3 persons) 600 4000 0.00

School per pupil 80 528 0.00 Assembly Hall per seat 10 66 0.00 Cinema per seat 10 66 0.00 Theatre per seat 10 66 0.00 Sports Hall per person 50 330 0.00

Hotel per room 550 3630 0.00 Guest House per room 200 1320 0.00 Motel per room 300 1980 0.00 Holiday Apartment per person 150 990 0.00

Leisure Park per person 220 1452 0.00 Caravan Pk standard per space 250 1650 0.00 Caravan Pk serviced per space 450 2970 0.00 Camping site standard per space 200 1320 0.00 Camping site serviced per space 350 2310 0.00

Public House per seat 150 990 0.00 Restaurant/Day Care Centre per person 270 1782 0.00 Drive in restaurant per seat 380 2508 0.00

Hospital per bed 750 4950 0.00 Nursing/Care Homes per bed 375 2475 0.00

Offices per 100m² 750 4950 7.9465 0.46 Shopping Centre per 100m² 400 2640 0.00

Warehouse per 100m² 150 990 0.00 Commercial premises per 100m² 300 1980 0.00 Manufacturing unit per 100m² 550 3630 0.00

Total Flow = 0.5 l/s (6x DWF)