Flood Risk Assessment and Drainage Strategy Report

Flood Risk Assessment and

Drainage Strategy Report 060304-PIN-XX-XX-RP-C-01 Staplehurst, North Site

C060304-PIN-XX-XX-RP-C-02

29 July 2021

Prepared for:

Pinnacle Consulting Engineers Limited Flood Risk Assessment and Drainage Strategy Report C060304-PIN-XX-XX-RP-C-02 Version 3.0 Staplehurst, North Site

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CONTACT DETAILS

Name Position Email Telephone Mobile

Ade Ogunsanya Graduate Civil

Engineer [email protected] 01707 527630

Iran Limbu Civil Engineer [email protected] 01707 527646

Max Deeble Senior Civil Engineer

[email protected] 01707 527670

Jawsy Jabbar Associate [email protected] 01707 527636 07920 721332

APPROVALS

Name Position Date

Prepared by Ade Ogunsanya Graduate Civil Engineer 29.07.21

Reviewed by Max Deeble

Senior Civil Engineer 29.07.21

Approved by Jawsy Jabbar

Associate 29.07.21

VERSIONS

This document has been prepared by Pinnacle Consulting Engineers Ltd. for the titled project and should

not be relied upon or used for any other project. Pinnacle Consulting Engineers Ltd accepts no

responsibility or liability for the consequences of this document being used for any purpose other than

the purpose for which it was commissioned. Any person using or relying on the document for such other

purpose agrees and will by such use or reliance be taken to confirm his agreement to indemnify Pinnacle

Consulting Engineers Ltd for all loss or resultant damage. Pinnacle Consulting Engineers Ltd accepts

no responsibility or liability for this document to any party other than the person by whom it was

commissioned.

Number By Date Context

1.0 Iran Limbu 18.06.2021 Draft Issue for Team Comments

2.0 Ade Ogunsanya 16.07.2021 Issue for Planning

3.0 Ade Ogunsanya 29.07.2021 Updated for NPPF 2021


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CONTENT

1 INTRODUCTION ............................................................................................................................4

2 EXISTING SITE CONDITIONS ......................................................................................................5

2.1 Site description.....................................................................................................................5

2.2 Topography ..........................................................................................................................5

2.3 Geological ground conditions ...............................................................................................5

2.4 Hydrogeology .......................................................................................................................8

2.5 Existing surface water management ................................................................................. 11

3 PROPOSED DEVELOPMENT .................................................................................................... 12

4 PROBABILITY OF FLOODING ................................................................................................... 13

4.1 Flooding from rivers (fluvial flooding) & sea (tidal flooding) .............................................. 13

4.2 Flooding from rivers (fluvial flooding) & sea (tidal flooding) .............................................. 14

4.3 Flooding from land & sewers ............................................................................................ 15

4.4 Flooding from groundwater ............................................................................................... 15

4.5 Flooding from reservoirs, canals, and other artificial sources .......................................... 16

4.6 Impact of climate change on rainfall intensity ................................................................... 16

4.7 Environment Agency Product 4 data ................................................................................ 16

5 PROPOSED SITE DRAINAGE ................................................................................................... 17

5.1 Surface water drainage strategy ....................................................................................... 17

5.2 Greenfield runoff rate ........................................................................................................ 17

5.3 Proposed development surface water drainage strategy ................................................. 18

5.4 Suds hierarchy .................................................................................................................. 18

5.5 Proposed foul water drainage strategy ............................................................................. 19

5.6 Maintenance requirements ............................................................................................... 19

6 POLICY STATUS FOR PROPOSED DEVELOPMENT ............................................................. 22

6.1 Vulnerability classification ................................................................................................. 22

6.2 Sequential test & exception test ........................................................................................ 23

6.3 Local policy ....................................................................................................................... 24

7 FLOOD RISK MANAGEMENT STRATEGY ............................................................................... 25

7.1 Flood mitigation measures ................................................................................................ 25

7.2 Surface water management strategy ................................................................................ 25

7.3 Foul water management strategy ..................................................................................... 26

8 CONCLUSIONS .......................................................................................................................... 27

APPENDIX A – SITE LOCATION PLAN ....................................................................................................

APPENDIX B – PROPOSED SITE LAYOUT .............................................................................................

APPENDIX C – IMPERMEABLE AND PERMEABLE AREA PLAN...........................................................


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APPENDIX D – PROPOSED DRAINAGE LAYOUT ..................................................................................

APPENDIX E – GREENFIELD RUNOFF RATE ESTIMATE .....................................................................

APPENDIX F – QUICK STORAGE ESTIMATE CALCULATIONS ............................................................

APPENDIX G – SOUTHERN WATER ASSET RECORD ..........................................................................


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1 INTRODUCTION

Pinnacle Consulting Engineers Ltd have been commissioned to prepare a Flood Risk Assessment (FRA)

and Drainage Strategy report for a proposed development of a residential units located south of George

Street, Staplehurst, TN12 0RA. A site location plan is enclosed in Appendix A.

With reference to the indicative flood maps published by the Environment Agency, the site appears to

lie entirely within a Flood Zone 1 area. This statement has been prepared in accordance with the

requirements contained within National Planning Policy Framework (NPPF, July 2021) and the

associated Planning Practice Guidance. The guidance refers to the Environment Agency’s “standing

advice” on flood risk. Based on requirements set by the Environment Agency, a Flood Risk assessment

is needed to support the planning application.

This statement has been prepared in accordance with (i) National Planning Policy Framework (NPPF),

(Department for Communities and Local Government, July 2021) and the accompanying (ii) Planning

Practice Guidance (Ministry of Housing, Communities and Local Government, March 2014); (iii)

Maidstone Borough Council Level 1 SFRA update and Level 2 SFRA, dated August 2020; and (iv) Other

statutory laws and local by laws and rules.

It is stated in Paragraph 30 of the Flood Risk and Coastal Change chapter of the Planning Practice

Guidance that “a site-specific flood risk assessment is carried out by (or on behalf of) a developer to

assess the flood risk to and from a development site. Where necessary, the assessment should

accompany a planning application submitted to the local planning authority. The assessment should

demonstrate to the decision-maker how flood risk will be managed now and over the development’s

lifetime, taking climate change into account, and with regard to the vulnerability of its users”.

This report has been prepared to address the requirements of the NPPF and has derived the following

data/information from various sources including:

• Information published or explicitly provided by the Environment Agency;

• Information published by the Local Planning Authority, including the SFRA;

• Enquiries made to relevant authorities to understand possible risks of flooding in the area; and

• Specific design works carried out for this report.


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2 EXISTING SITE CONDITIONS

2.1 Site description

The proposed development is centred at National Grid Reference (NGR) TQ784445 [578400, 144513]

and located south of George Street, Staplehurst, TN12 0RA. The plot is of a triangular shape with a total

developable area of approximately 3.005ha, is greenfield and currently contains three ponds and a

drainage ditch which enters the site from the south and continues north for about 110m before turning

towards the eastern boundary where by it continues off site.

The site is bounded to the south by Staplehurst rail station, to the east by A229 road and the north-west

by George Street. All boundaries have been established with dense hedgerows (see Appendix A and

Figure 2.1 below). There appears to be no formal routes, bridleways or paths crossing the site, but the

western tip abuts a pedestrian right of way leading to the west. The nearest river (River Beult) is located

approximately 1.00km east of the site.

Figure 2.1 - Aerial View of the existing development site (approximate site boundary edged in red) © Google

2020

2.2 Topography

A topographical survey was carried out in March 2002 (L2264/1), indicates that the site falls towards the

north-east corner, ranging from 21.92m AOD in the south-west corner to 19.66m AOD in the north-east

corner. The site slopes steeply upwards to meet A229 road at 25.18m AOD in the south-east corner of

the site to tie in with the road levels at the bridge crossing over the railway line. There are a series of

low points across the site associated with the bottom of the ponds and ditches.

2.3 Geological ground conditions

Geological conditions at the site are detailed below and are based on a British Geological Survey (BGS)

maps found online. The focus of an FRA study on geology is on the potential movement of water through

Made Ground, Drift Geology and Solid Geology.

These strata are depicted in Figure 2.2 & Figure 2.3 and outlined in Table 2.1.

`


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Figure 2.2 - British Geological Survey Superficial Geology Extract (approximate site location denoted by arrow)

No superficial deposits have been recorded within the boundary of the site.

Figure 2.3 - British Geological Survey Bedrock Geology Extract (approximate site location denoted by

arrow)

The proposed site lies within a bedrock zone identified as part of the Weald Clay Formation – Mudstone.


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Formation Description

Artificial Ground

(Made Ground)

The site is a greenfield site.

Superficial

Deposits (Drift

Deposits)

No superficial deposits have been recorded within the boundary of the site.

Bedrock Weald Clay Formation - Mudstone. Sedimentary Bedrock formed

approximately 126 to 134 million years ago in the Cretaceous Period. Local

environment previously dominated by swamps, estuaries and deltas.

Table 2.1 – Geological Ground Conditions

The focus of an FRA study with regard to soils is to determine the drainage characteristics specific to

the local composition, in order to produce a definitive solution regarding the use of shallow infiltration

SUDS devices. The available soil data developed by Cranfield University is provided in figure 2.4 below

with accompanying text.

Figure 2.4 shows that the proposed site lies within ‘slowly permeable seasonally wet slightly acid but

base-rich loamy and clayey soil’.

Figure 2.4 – Soilscape Map of the site (approximate site location denoted by ribbon)


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2.4 Hydrogeology

The hydrogeological information of the site is taken from Defra Magic Maps. The hydrogeological

features of the site are depicted below in Figures 2.5 to 2.8. A summary and further information can be

found in Table 2.3.

Figure 2.5 - Source Protection Zone Map Extract (approximate site boundary edged in red)

Figure 2.5 shows that the proposed site lies outside the Groundwater Source Protection Zones.

SITE


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Figure 2.6 - Source Vulnerability Zone Map Extract (approximate site boundary edged in red)

Figure 2.6 shows that the proposed site lies within an ‘Unproductive’ Groundwater Vulnerability Zone.

Figure 2.7 - Aquifer Designation Map Extract (Bedrock) (approximate site location denoted by arrow)

Figure 2.7 shows that the proposed site lies within an ‘Unproductive’ Bedrock Aquifer Designation.

SITE

`

SITE

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Figure 2.8 - Aquifer Designation Map Extract (superficial drift) (approximate site location denoted by arrow)

Figure 2.8 shows that the proposed site lies within an ‘Unproductive’ Superficial Aquifer Designation zone.

Map Dataset Designation Comment

Groundwater

Source

Protection Zone

None This category identifies zones at risk from contamination from any

activities that might cause pollution in the area. The closer the activity

the greater the risk.

According to available records depicted in Figure 2.5 the proposed site

does not fall within any Ground Water Source Protection Zone.

Groundwater

Vulnerability

Zone

Unproductive This category classifies the underlying groundwater in terms of

vulnerability from activities carried out on the surface.

Figure 2.6 identifies that the site has a ‘Unproductive’ designation which

consist of areas comprised of rocks that have negligible significance for

water supply or baseflow to rivers, lakes and wetlands. They consist of

bedrock or superficial deposits with a low permeability that naturally

offer protection to any aquifers that may be present beneath.

Aquifer Maps:

Bedrock

Deposits

Designation

Unproductive This identifies the type of aquifer present in solid permeable formations.



water supply or baseflow to rivers, lakes and wetlands.

Aquifer Maps:

Superficial

Deposits

Designation

Unproductive This identifies the type of aquifer present in the permeable

unconsolidated (loose) deposits.



water supply or baseflow to rivers, lakes and wetlands.

Table 2.3: Summary of Hydrogeological conditions

SITE

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2.5 Existing surface water management

The site is entirely greenfield and no formal piped drainage systems are identified within the site

boundaries (see Appendix G for the Southern Water asset report) leading to surface water flowing

across the surface to be collected by existing watercourses.


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3 PROPOSED DEVELOPMENT

The proposed development (refer to Appendix B) consists of 61 residential units, with associated

parking, infrastructure, and amenity space. A new access road is proposed directly from George Street

to the north-east of the site. The proposals will allow pedestrians and cyclists to safely traverse the site

by connecting the open spaces to the existing footpath to the A229. Subject to later negotiation, a direct

link to the station maybe possible. The proposed site layout retains two of the existing three ponds plus

the ditch towards the eastern boundary.


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4 PROBABILITY OF FLOODING

The NPPF identifies six potential sources of flooding: -

• Flooding from rivers (fluvial flooding);

• Flooding from the sea (tidal flooding);

• Flooding from land;

• Flooding from sewers;

• Flooding from groundwater; and

• Flooding from reservoirs, canals, and other artificial sources.

These are considered below.

4.1 Flooding from rivers (fluvial flooding) & sea (tidal flooding)

The assessment of flood risk in this report is based on the definitions in Table 1 in the Flood Risk and

Coastal Change, Planning Practice Guidance, which recognises the following Flood Zones:

• Flood Zone 1 - little or no risk, with annual probability of flooding from rivers and the sea of less

than 0.1% (1 in 1000-year)

• Flood Zone 2 - low to medium risk, with annual probability of flooding between 0.1% and 1.0%

from rivers and between 0.1% and 0.5% from the sea

• Flood Zone 3a - high risk of flooding with an annual probability of flooding of 1.0% or greater

from rivers, and 0.5% or greater from the sea.

• Flood Zone 3b – the ‘Functional Floodplain’ with an annual probability of flooding of 5% or

greater.

The EA Risk of Flooding from Rivers and Sea map is published on the EA website. It shows of the

likelihood of flooding from rivers and the sea at any location. Their assessment is based on the presence

and effect of all flood defences, predicted flood levels, and ground levels.

The three EA Risk of Flooding Maps (Rivers and Seas, Surface Water and Reservoirs) display the

chance of flooding in any given year in four categories:

• High: An AEP greater than 3.3% (1 in 30) chance.

• Medium: An AEP between 1% (1 in 100) and 3.3% (1 in 30) chance.

• Low: An AEP between 0.1% (1 in 1,000) and 1% (1 in 100) chance.

• Very Low: An AEP of less than 0.1% (1 in 1,000) chance.


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An extract from the Environment Agency’s online flood map published online is shown in Figure 4.1

below. The site is located entirely within Flood Zone 1.

Figure 4.1 - EA Online Flood Map Extract (approximate site boundary edged red)

4.2 Flooding from rivers (fluvial flooding) & sea (tidal flooding)

Figure 4.2 below shows that the proposed site is not at risk of flooding from rivers or the sea.

Figure 4.2 - EA Online Flood Risk from Rivers/Sea Map Extract (approximate site boundary edged red)

SITE

SITE


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4.3 Flooding from land & sewers

Figure 4.3 below shows the site is at a ‘low’ to ‘high’ risk of flooding from surface water. The high risk of

surface water flooding is located along north-west boundary and eastern boundary, around the existing

ponds and ditches. Additionally, low to medium flooding risk occurs across the centre of the site.

Figure 4.3 - EA Online Flood Risk from Surface Water Map Extract (approximate site boundary edged red)

4.4 Flooding from groundwater

The JBA groundwater flood map (attached as Figure 4.4) provided in the Maidstone Borough Council

Strategic Flood Risk Assessment, dated August 2020, indicates that the proposed site is not at risk of

groundwater flooding.

Figure 4.4 - Ground Water Flood Risk Map adapted from Maidstone Borough Council Strategic Flood Risk

Assessment (approximate site location denoted by arrow)

SITE

SITE


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4.5 Flooding from reservoirs, canals, and other artificial sources

As shown in Figure 4.5 below, the site is predicted to be not at risk of flooding from reservoirs, canals

or any other artificial sources.

Figure 4.5 - EA Flood Risk from Reservoirs Sources Map Extract (approximate site boundary edged red)

4.6 Impact of climate change on rainfall intensity

The EA recommends an allowance of 20-40% should be made to account for the increase in rainfall

intensity with respect to climate change, as shown in Table 4.1 below. Kent County Council (KCC) state

that the drainage design should accommodate up to the 1 in 100 year storm with a 20% allowance for

climate change event, with an additional analysis undertaken to understand the flooding implication for

a greater climate change allowance of 40%.

Applies across all of

England

Total potential change

anticipated for the

‘2020s’ (2015 to 2039)


anticipated for the

‘2050s’ (2040 to 2069)


anticipated for the

‘2080s’ (2070 to 2115)

Upper End 10% 20% 40%

Central 5% 10% 20%

Table 4.1 - Peak rainfall intensity allowance in small and urban catchments (Table 2 - https://www.gov.uk/guidance/flood-risk-assessments-climate-change-allowances)

4.7 Environment Agency Product 4 data

The product 4 data for the proposed development have been requested from the Environment Agency.

This report will be updated upon receipt of the Product 4 information.

SITE

https://www.gov.uk/guidance/flood-risk-assessments-climate-change-allowances


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5 PROPOSED SITE DRAINAGE

5.1 Surface water drainage strategy

Traditional approaches to urban drainage have comprised of underground tanks and pipe networks.

More recently, the benefits and opportunities to use Sustainable Drainage Systems (SuDS) have been

realised and encouragement to use such systems is promoted throughout Flood Risk Management

policy at all levels. SuDS is a term which encompasses a variety of approaches to managing surface

water in a way which is more sympathetic to the natural and human environment than conventional

piped drainage systems. Management of surface water is an essential element for reducing flood risk

and SuDS techniques are often designed to achieve this in a way that mimics the natural environment.

The Building Regulations (H3) states the priority for discharging surface water runoff from a development

is as follows:

1. Infiltration into the ground;

2. Discharge into a watercourse;

3. Discharge into a sewer.

In conjunction with Building Regulations H3 and national planning practice guidance, the primary

approach to the drainage of surface water runoff must be subject to the results of an infiltration test

commissioned on the development site. However, infiltration is not an appropriate based on information

provided within the Ground Engineering Limited’s ground investigation report dated May 2002,

groundwater levels under the site varied between 0.03m to 6.30m bgl. In addition to the composition of

the stratum underlying the site comprises of slowly permeable seasonally wet slightly acid but base-rich

loamy and clayey soil.

The next method of discharge in conjunction to Building Regulation H3 would be to discharge into the

nearest watercourse. This report therefore proposes to discharge into the existing pond and the ditch

adjacent the eastern boundary to maintain flows in the receiving watercourses and mimic natural

hydrological processes.

Southern Water has also been consulted for pre-application advice for the proposed site. This report will

be updated once the information has been received.

5.2 Greenfield runoff rate

An estimate of the greenfield runoff rate for the site has been carried out and is included in Appendix E.

Based on the IH124 method, the greenfield runoff rate from the proposed impermeable area (1.350ha)

is shown in Table 5.1 below.

Return Period Greenfield Runoff Rate (l/s)

1 Year 5.24

Qbar 6.17

30 Year 14.19

100 Year 19.68

Table 5.1 - Greenfield Runoff Rate estimates based on Return Period


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5.3 Proposed development surface water drainage strategy

The Kent LLFA Local Standards and Guidance indicates that drainage discharge rates should be

designed to match greenfield runoff rates as far as possible. It is therefore proposed to limit the discharge

rate to match the greenfield runoff (6.17l/s Qbar) rate using SuDS/ storage features and a flow control

device (Hydro-Brake) before discharging into the existing pond and the ditch at the south-east corner of

the site. In order to reach the ditch, a short length of pipe culvert is proposed between the pond and the

ditch.

The surface water runoff from the proposed impermeable area of 1.350ha (45% of the proposed 3.005ha

site) will be distributed into two surface water networks (see Appendix D).

Both surface water networks comprise of permeable paving (tanking) beneath shared driveways and

car parking courts. This paving will intercept rainfall and provide an element of source control and water

quality which will progress through proposed cellular attenuation units before discharging into the

existing watercourses at a controlled discharge rate of 6.17l/s. Areas of highways and hardstanding that

will not drain via permeable pavements are proposed to be drained through trapped gullies and a bypass

oil separator. A gravity pipe system will convey all surface water runoff to the existing watercourses.

Conventional storage will also be required to accommodate surface water runoff for events up to and

including a 1 in 100 year storm event + 20% climate change. Based on the Quick Storage Estimate

Calculations carried out in MicroDrainage (see Appendix F), a maximum attenuation capacity of 1376m3

will be required for the proposed development site. Site attenuation storage will be provided by

permeable paving (151m3) and cellular attenuation units (1225m3).

5.4 Suds hierarchy

The surface water drainage proposed will incorporate a number of SuDS measures in line with best

practice guidance. The feasibility of different SuDS techniques is outlined in Table 5.2 below.

SuDS Technique Can they be feasibly

incorporated into the site?

Reason

Green Roofs ☓ No green roofs are proposed for the

development due to cost and maintenance

issues.

Basins and Ponds ✓ Proposed to promote water quality and

surface water storage by utilising the

existing ponds and ditches

Filter Strips and Swales ☓ Not proposed due to land constraints.

Permeable Structures ✓ Lined Permeable Paving is proposed as

part of the development to provide water

quality and some water storage.

Rainwater Harvesting ☓ No rainwater harvesting is proposed as the

site is primarily residential. However, water

butts for each property could be proposed.


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Tanked Systems ✓ A sub-surface cellular tanked system is

proposed as part of the surface water

drainage system.

Table 5.2 - Greenfield Runoff Rate estimates based on Return Period

5.5 Proposed foul water drainage strategy

The drainage strategy (refer to Appendix C) proposes to discharge foul water flows into Southern Water

public foul water manhole 5602 located within George Street, in the north-east corner of the site (refer

to Appendix G). This is dependent on the site levels strategy and may require multiple discharge points

into the public foul water sewer. A pre-planning assessment to Southern Water has been submitted to

confirm if the existing public foul water infrastructure has adequate capacity to receive the flows from

the proposed development.

5.6 Maintenance requirements

It is anticipated that a private management company will be employed to maintain the completed

drainage network for the development incorporating the following activities and frequency for each

SUDS component.

5.6.1 Gullies/channels/pipes/manholes

All components are to be periodically cleaned of foreign particles and silt accumulation, on a quarterly

basis. Components located in unadopted areas will be maintained by the landowner. Those located in

adopted areas will be maintained by the adopting authority.

5.6.2 Permeable pavements

Many of the specific maintenance activities for permeable pavements can be undertaken as part of a

general site cleaning contract. A guidance on the type of operational and maintenance requirements is

detailed in table 20.15 from the CIRIA SuDS manual.


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5.6.3 Cellular attenuation storage unit

The proposed Geolight (or equivalent) attenuation unit includes a perforated/ slotted distribution pipe

surrounded by granular material providing filtration and treatment for surface water flows. This will be

installed with an associated filtration device (oil separator, trapped gulley or other) to prevent the intake

of debris and the treatment of hydrocarbon mixed in the surface water runoff. Size of the attenuation

unit must be appropriate for the scale and nature of the development. A typical maintenance schedule

is detailed below in table 13.1 and 21.3 respectively from the CIRIA SuDS manual.


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5.6.4 Pond/ditch

Ponds will require regular maintenance to ensure continuing operation to design performance

standards. Litter and debris removal should be undertaken as a part of general landscape maintenance

of the site. Any invasive maintenance work such as silt or vegetation removal is typically only required

intermittently. Vegetation should be trimmed as necessary to keep the pond free of leaves and for

aesthetic and safety reasons. Sediment management will have to take place occasionally which should

be disposed of in accordance with current waste management legislation.

5.6.5 Proprietary systems

Proprietary systems will require routine maintenance by the owner to ensure continuing operation to

design performance standards. A typical maintenance schedule is detailed below in table 14.2 from the

CIRIA SuDS manual.


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6 POLICY STATUS FOR PROPOSED DEVELOPMENT

6.1 Vulnerability classification

The proposed development complies with the following principles:

• The proposed development lies within Flood Zone 1;

• The proposed development is classified as ‘More Vulnerable’ in accordance with Table 2 of the

Flood Risk and Coastal Change, Planning Practice Guidance (reproduced as Table 6.1 below).

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

Solar Farms

Highly Vulnerable

Police stations, Ambulance stations, Fire stations, 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 use

Installations requiring hazardous substances consent

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.

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.

Sewage treatment works (if adequate measures to control pollution and manage sewage

during flood events are in place).

Car Parks

Water-compatible

Development

Flood control infrastructure.

Water transmission infrastructure, pumping stations.

Sewage transmission infrastructure and pumping stations.

Sand and gravel workings.


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Docks, marinas, wharves

Navigation facilities.

Ministry of 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.

Notes

1 - This classification is based partly on Defra/Environment Agency research on Flood Risks to People

(FD2321/TR2)21 and also on the need of some uses to keep functioning during flooding.

2 - Buildings that combine a mixture of uses should be placed into the higher of the relevant classes of flood

risk sensitivity. Developments that allow uses to be distributed over the site may fall within several classes of

flood risk sensitivity.

3 - The impact of a flood on the particular uses identified within this flood risk vulnerability classification will

vary within each vulnerability class. Therefore, the flood risk management infrastructure and other risk

mitigation measures needed to ensure the development is safe may differ between uses within a particular

vulnerability classification.

Table 6.1 - Flood Risk Vulnerability Classification

Vulnerability Classification

Essential

Infrastructure

Water-compatible

Highly Vulnerable

More Vulnerable

Less Vulnerable

Flo

od Z

one

Zone 1 ✓ ✓ ✓ ✓ ✓

Zone 2 ✓ ✓ Exception Test ✓ ✓

Zone 3a Exception Test ✓ Exception Test ✓

Zone 3b Exception Test ✓

Key

✓ Development is appropriate

Development should not be permitted

Table 6.2 - Flood Risk Vulnerability and Flood Zone ‘Compatibility’

The proposed development is appropriate in accordance with Table 3 of the Flood Risk and Coastal

Change, Planning Practice Guidance, reproduced in Table 6.2 above.

6.2 Sequential test & exception test

The NPPF requires that all development is sequential tested to steer new development to areas at the

lowest probability of flooding (Flood Zone 1). The Sequential Test would normally be completed by the

Local Planning Authority (LPA) to inform the preparation of the Local Development Framework (LDF),


24

where one exists. However, where this process has not yet been completed the onus for the provision

of evidence demonstrating successful application of the Sequential Test falls to the developer, or

promoter of the site. The NPPF also requires the layout of a site to be sequentially tested to locate the

most vulnerable land uses in the areas at lowest risk of flooding.

The NPPF Planning Practice Guidance acknowledges that in some circumstances it may not be possible

to locate development in areas of low or appropriate (considering development vulnerability) flood risk

or that there may be other valid reasons for a development to take place within the floodplain. In these

circumstances, it is necessary to apply the Exception Test to clearly demonstrate that the benefits for

development of a site outweigh the flood risks to the development and its occupants. Table 3 of the

Flood Risk and Coastal Change, Planning Practice Guidance (reproduced in Table 6.2 above) indicates

when the Exception Test is required.

The proposed development site falls entirely into Flood Zone 1, meaning the Sequential Test is deemed

to be passed and the Exception Test is not required.

6.3 Local policy

Kent County Council’s Drainage and Planning Policy which was adopted in December 2019 sets out the

following requirements for developments on greenfield and previously developed sites:

• For developments on greenfield sites peak runoff rates from the 1 in 1-year (100% AEP) to the

1 in 100-year (1% AEP) rainfall events should be limited to the peak greenfield runoff rates for

the same events.

• For developments on brownfield sites, the peak runoff rate must be as close as reasonably

practicable to the greenfield runoff rate but should never exceed the existing rate of discharge

prior to redevelopment. Unless it can be demonstrated to be reasonably impracticable, a 50%

reduction in the peak runoff rate is expected.

• The drainage system must be designed to operate without flooding on any part of the site during

any rainfall event up to (and including) a 1 in 30- year (3.3% AEP) rainfall event.

• The drainage system must also be designed to operate without flooding in any building up to

(and including) a 1 in 100-year (1% AEP) plus climate change rainfall event, without exacerbating

off-site flood risk.

• Exceedance flows that cannot be managed within the drainage system must be managed via

exceedance flow routes that minimise the risks to people and property.

• Attenuation storage volumes provided by drainage areas must half empty within 24 hours to

enable runoff from subsequent storms to be received. If the time taken to drain from full to empty

exceeds 24 hours long duration events should be assessed to ensure drainage is not negatively

impacted by inundation.

The Lead Local Flood Authority (LLFA) has been contacted for pre-application advice for the

proposed site. This report will be updated once the information has been received.


25

7 FLOOD RISK MANAGEMENT STRATEGY

7.1 Flood mitigation measures

NPPF guidance advises that an FRA should take into account the flood risk to people in terms of ‘public

safety issues’, access/egress to/from and evacuation/rescue from the site.

The site itself poses ‘little to no flood risk’ of flooding as it lies within Flood Zone 1. However, as

evidenced in Figure 4.3, the site is at a ‘low to high’ risk of flooding from surface water. The high risk of

surface water flooding is located along north-west boundary and eastern boundary, around the existing

ponds and ditches. Additionally, ‘low to medium’ flooding risk occurs across the centre of the site. JBA

has been instructed to carry out a baseline and post-development hydrological assessment to simulate

the flood extents, levels and flows through time in relation to the site. This report will be updated once

the Hydraulic Study outcome is made available.

7.1.1 Public safety issues

Given the relatively very low risk of flooding across the entire site, there is no requirement to develop a

Flood Evacuation Plan to address public safety issues, nor are flood resilient construction methods

deemed necessary.

7.1.2 Safe access/egress

The risk of surface water flooding around the new access road proposed directly from George Street at

the north-east of the site is categorised as ‘low to medium’. Subject to JBA post-development hydraulic

modelling results, we will confirm the flood risk to the site access and, if required, alterations needed to

the proposal.

Should there be any flood risk within the vicinity of the site it is advised that occupants remain on the

premises. If evacuation is required, this should be done via Station Road.

7.1.3 Flood risk elsewhere

The proposed surface water network will be positively drained, comprising on-site surface water storage

units which eliminates all foreseeable flood risk within the site. The proposed modifications are localised

and are not expected to increase the potential of flooding to neighbouring property. Further mitigative

measures for the proposed development which may be recommended include:

• Restricting the surface water flow to a prescribed discharge rate and ensuring there is sufficient

attenuation capacity for a 100 year, with 20% climate change, event.

• Ensure managed surface water and exceedance flood flows are diverted away from the

surrounding buildings.

• Exceedance flood flows should be guided into the landscaped areas of the site or into the car

parking areas.

7.2 Surface water management strategy

The NPPF guidance states that developers and local authorities should not increase flood risk elsewhere

due to site development. Additionally, developers should aim to reduce the overall risk of flooding for

the area with the appropriate application of SUDS.

The proposed additions are localised, are not expected to increase the potential of flooding to

neighbouring property and further employment of SuDS are not feasible.


26

7.2.1 Discharge strategy

Infiltration is not a viable method of discharging surface water runoff due to shallow groundwater levels

beneath the site in addition to the composition of the stratum underlying the site comprises of slowly

permeable seasonally wet slightly acid but base-rich loamy and clayey soil. This report therefore

proposes to discharge into the existing pond and the ditch adjacent the eastern boundary to maintain

flows in the receiving watercourses and mimic natural hydrological processes.

7.2.2 Drainage strategy design

The surface water runoff from the proposed impermeable area of 1.350ha (45% of the proposed 3.005ha

site) will be distributed into two surface water networks comprising of SuDS/ storage features and a flow

control device (Hydro-Brake) limiting the discharge rate to match the greenfield runoff (6.17l/s Qbar)

before discharging into the existing pond and the ditch at the south-east corner of the site.

7.3 Sustainable Drainage Systems (SuDS)

Our proposals comprise the capture and retention of surface water runoff through the implementation

of SuDS devices, including permeable paving, geo-cellular attenuation, open pond structures and

ditches.

7.4 Foul water management strategy

The drainage strategy proposes to discharge foul water flows into Southern Water public foul water

manhole 5602 under George Street, in the north-east corner of the site subject to the results of a pre-

development enquiry.


27

8 CONCLUSIONS

The proposed site is of a triangular shape with a total developable area of approximately 3.005ha, is greenfield and currently contains three ponds and a drainage ditch towards the eastern boundary. The proposed site is located in Flood Zone 1 with little or no risk of flooding from rivers and seas. The site has 'low' to 'high' risk of flooding from surface water, especially concentrated around the existing surface water features. Hydraulic study will determine the extent of surface water flooding and the proposed FFL requirements for the development. Infiltration is not a viable method of discharging surface water due to shallow groundwater table and existing ground profile. Proposed surface water discharge system will be limited to the greenfield runoff rate and will discharge into the existing ponds. Proposed foul water runoff will be discharged into the existing Southern Water public sewer.

Proposed development will not increase the flood risk elsewhere.

In accordance with NPPF guidance, the proposed development is deemed acceptable, therefore the

level of flood risk is considered acceptable for the vulnerability class.

Pinnacle Consulting Engineers Limited Flood Risk Assessment and Drainage Strategy Report C060304-PIN-XX-XX-RP-C-02 Staplehurst, North Site

Appendix A – Site Location Plan

NORTH

NOTES

Date

Title

Scale

CheckedDrawn

Drawing Number Revision

Project

This drawing to be read in accordance with the specification/Bills ofQuantities and related drawings.No Dimensions to be scaled from this drawing. All stated dimensions to beverified on site and the Architect notified of any discrepancies.

0 70

Scale bar 70mm at 1:1

saundersarchitects.com | 01707 385300 | London | Manchester | Bristol | Welwyn

c

PROPOSED RESIDENTIALDEVELOPMENTSTAPLEHURST

SITE LOCATION PLAN

1:1000 A2 OCT 2020

SG GMW

8313/SK01 -

@

REV. DATE NOTE INREV. DATE NOTE IN

- - - -


Appendix B – Proposed Site Layout

NORTH

MARKET STREET

WILLO

W CRES

STATION APPROACH

1 to

6

17

Douglas Buildings1

1 to 6

5

10

1

18

14

7

1

18

109

1

7a

7k

Dickens Court

Works

Crump House

Hone

ycre

st In

dust

rial P

ark

LG

Path

Pond

Pond

Po

nd

Brickfie

ld

Ho

use

Brickfie

ld

Co

ttag

e

Pond

The Grange

GEORGE STREET

Pond

1

Level Crossing

STATION RO

AD

V

V

VV

V V

V

V

V

V

V

V

OPEN SPACEAPPROX 0.07HA



PUBLIC FOOTPATHSTATION BUILDING

STATION PLATFORM

MOBILEPYLON

FOOTPATH TO MOBILE PYLON

STATION PLATFORM

EXTERNALSEATING AREA

FOR CAFE

Pond

Pond

RAMP TO PLATFORM STAIRS TO PLATFORM

GEORGE STREET

MAIDSTO

NE ROAD

COVERED WALKWAY TO STATION

PUBLIC FOOTPATH

1-6

8

13

1415

1617

1819

20

21

22-27

282931

30

42 43 44 45 46 47 4849 50 51 52 53 54 55

5758 59

56 60

61

32-37

38-41

9-12

7

PROPOSED RESIDENTIALDEVELOPMENTGEORGE STREETSTAPLEURST

ILLUSTATIVE SITE PLAN

1:500 A0 MAY 2021

SG RC

8313/SK210 A

@

NOTES c

This drawing to be read in accordance with the specification/Bills ofQuantities and related drawings.

No Dimensions to be scaled from this drawing. All stated dimensions to beverified on site and the Architect notified of any discrepancies.

0 100

Scale bar 100mm at 1:1

Date

Title

Scale

CheckedDrawn

Drawing Number Revision

Project

saundersarchitects.com | 01707 385300 | London | Manchester | Bristol | Welwyn

REV. DATE NOTE INREV. DATE NOTE IN

A 09.06.21 AMENDED TO SUIT HIGHWAY ENGINEERS ADVICE SG


Appendix C – Impermeable and Permeable Area Plan

GEORGE STREE

T

LEGEND

SITE BOUNDARY

IMPERMEABLE AREA

PERMEABLE AREA

Crump House

LG

Path

Pond

Pond

Level Crossing

GEORGE STREE

T

V

V


VVV V

V

V

1-6

8

1314

1516

1718

1920

21

22-27

282931

30

42 43 44 45 46 47 48 49 50 51 52 53 54 55

5758 59

56 60

61

32-37

38-41

V

V

V

V9-12

7



P01 FOR DRAFT IL 18.06.21JJ

N

GENERAL NOTES1. DO NOT SCALE THIS DRAWING. WORK ONLY TO

FIGURED DIMENSIONS.

2. FOR ALL RELEVANT NOTES, REFER TOSTRUCTURAL AND CIVIL ENGINEERINGPERFORMANCE SPECIFICATION.

3. ANY DISCREPANCIES ARE TO BE REPORTED TOPINNACLE CONSULTING ENGINEERS IMMEDIATELY.

4. THIS DRAWING IS TO BE READ IN CONJUNCTIONWITH ALL OTHER RELEVANT ENGINEERS,ARCHITECTS AND SUB-CONTRACTORS DRAWINGSAND DETAILS.

REVISIONDRG NO.

SCALE @ A1 DATE DRAWN BY CHECKED

REV DESCRIPTION BY CHK DATE

COPYRIGHT PINNACLE

PROJECT

DRAWING TITLE

REF:

DRAWING STATUS

CLIENT

ALCHEMY,BESSEMER ROAD,WELWYN GARDEN CITY,HERTS,AL7 1HE. TELEPHONE: 01707 527 630NORWICH LONDON DUBLIN THE HAGUE

060304

STAPLEHURSTSTATION APPROACH

IMPERMEABLE AND PERMEABLEAREA PLAN NORTH SITE

C060304-PIN-XX-XX-DR-C-0203 P02

PLANNING

1:1000 JUNE' 21 IL JJ

TOTAL IMPERMEABLE AREA = 0M2

TOTAL PERMEABLE AREA = 30,050M2

TOTAL AREA = 30,050M2

EXISTING SITE

PROPOSED SITETOTAL IMPERMEABLE AREA = 13,500m2

TOTAL PERMEABLE AREA = 16,550m2

TOTAL AREA = 30,050m2

P02 ISSUE FOR PLANNING IL 16.07.21JJ

AutoCAD SHX Text

Staplehurst Station

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SB

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Crump House

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ROMAN ROAD

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23.0m

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Car Park

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FB

AutoCAD SHX Text

MP 41.75

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Level Crossing

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LG

AutoCAD SHX Text

Path

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Pond

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Pond

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Drain

AutoCAD SHX Text

Pond

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Pond

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4650

AutoCAD SHX Text

3152

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Pond

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Brickfield

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House

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Brickfield

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Cottage

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Pond

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The Grange

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Pond

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6

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1

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2

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1

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Yew Tree House

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Dane Mead Villas

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MP 42

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Pond

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Drain

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Pond

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Pond

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6541


Appendix D – Proposed Drainage Layout

10

GEORGE STREE

T

V

V


VVV V

V

V

1-6

8

1314

1516

1718

1920

21

22-27

282931

30

42 43 44 45 46 47 48 49 50 51 52 53 54 55

5758 59

56 60

61

32-37

38-41

V

V

V

V9-12

7



PROPOSED CELLULAR ATTENUATION TANK(SDS GEOLIGHT OR SIMILAR APPROVED)5m X 30m + 2.5m X 20m X 1m (Dp) 95% VOIDREQUIRED STORAGE VOLUME= 198m³

PROPOSED CELLULAR ATTENUATION TANK(SDS GEOLIGHT OR SIMILAR APPROVED)11.5m X 5m X 1m (Dp) 95% VOIDREQUIRED STORAGE VOLUME= 55m³

PROPOSED CELLULAR ATTENUATION TANK(SDS GEOLIGHT OR SIMILAR APPROVED)34.5m X 5m X 1m (Dp) 95% VOIDREQUIRED STORAGE VOLUME= 164m³

PROPOSED CELLULAR ATTENUATION TANK(SDS GEOLIGHT OR SIMILAR APPROVED)58m X 5m X 1m (Dp) 95% VOIDREQUIRED STORAGE VOLUME= 276m³





HYDRO-BRAKE MANHOLELIMITING FLOW TO 6.17l/s

POROUS PAVINGTOTAL APPROXIMATE AREA OF POROUS PAVEMENT = 1050m²;DEPTH OF SUB-BASE = 450mm;32% VOID;REQUIRED STORAGE VOLUME= 151M³

LEGENDSITE BOUNDARY

PROPOSED HEADWALL

PROPOSED PRIVATESURFACE WATER SEWER

PROPOSED PERMEABLEPAVING TO PARKINGSPACES (TYPE C TANKING)

PROPOSED PRIVATEFOUL WATER SEWER

EXISTING PUBLIC FOULWATER SEWER

PROPOSED ATTENUATIONTANK

PERFORATED PIPE

P01 FOR DRAFT IL 18.06.21JJ

N

GENERAL NOTES1. DO NOT SCALE THIS DRAWING. WORK ONLY TO

FIGURED DIMENSIONS.

2. FOR ALL RELEVANT NOTES, REFER TOSTRUCTURAL AND CIVIL ENGINEERINGPERFORMANCE SPECIFICATION.

3. ANY DISCREPANCIES ARE TO BE REPORTED TOPINNACLE CONSULTING ENGINEERS IMMEDIATELY.

4. THIS DRAWING IS TO BE READ IN CONJUNCTIONWITH ALL OTHER RELEVANT ENGINEERS,ARCHITECTS AND SUB-CONTRACTORS DRAWINGSAND DETAILS.

REVISIONDRG NO.

SCALE @ A1 DATE DRAWN BY CHECKED

REV DESCRIPTION BY CHK DATE

COPYRIGHT PINNACLE

PROJECT

DRAWING TITLE

REF:

DRAWING STATUS

CLIENT

ALCHEMY,BESSEMER ROAD,WELWYN GARDEN CITY,HERTS,AL7 1HE. TELEPHONE: 01707 527 630NORWICH LONDON DUBLIN THE HAGUE

060304

STAPLEHURSTSTATION APPROACH

PROPOSED DRAINAGE LAYOUTNORTH SITE

C060304-PIN-XX-XX-DR-C-0202 P02

PLANNING

1:500 JUNE' 21 IL JJ

50mm ON A1 DWG.0 50

P02 ISSUE FOR PLANNING IL 16.07.21JJ

AutoCAD SHX Text

10

AutoCAD SHX Text

Staplehurst Station

AutoCAD SHX Text

SB

AutoCAD SHX Text

Crump House

AutoCAD SHX Text

Car Park

AutoCAD SHX Text

TCBs

AutoCAD SHX Text

Car Park

AutoCAD SHX Text

Level Crossing

AutoCAD SHX Text

Pond

AutoCAD SHX Text

The Grange

AutoCAD SHX Text

Pond


Appendix E – Greenfield Runoff Rate Estimate

Greenfield runoff rateestimation for sites

www.uksuds.com | Greenfield runoff tool

Calculated by: Iran Limbu

Site name: North Site

Site location: Staplehurst

Site Details

Latitude: 51.17210° N

Longitude: 0.55077° EThis is an estimation of the greenfield runoff rates that are used to meet normal best practice criteria in line with Environment Agency guidance “Rainfall runoff management for developments”, SC030219 (2013) , the SuDS Manual C753 (Ciria, 2015) and the non-statutory standards for SuDS (Defra, 2015). This information on greenfield runoff rates maybe the basis for setting consents for the drainage of surface water runoff from sites.

Reference: 3316002086

Date: Jun 18 2021 11:07

Runoff estimation approach IH124

Site characteristics

Total site area (ha): 1.350

Methodology

Q estimation method: Calculate from SPR and SAARSPR estimation method: Calculate from SOIL type

Soil characteristicsDefault Edited

SOIL type: 4 4HOST class: N/A N/ASPR/SPRHOST: 0.47 0.47

Hydrological characteristicsDefault Edited

SAAR (mm): 668 668Hydrological region: 7 7Growth curve factor 1 year: 0.85 0.85Growth curve factor 30 years: 2.3 2.3Growth curve factor 100 years: 3.19 3.19Growth curve factor 200 years: 3.74 3.74

Notes

(1) Is Q < 2.0 l/s/ha?

When Q is < 2.0 l/s/ha then limiting discharge rates are set at2.0 l/s/ha.

(2) Are flow rates < 5.0 l/s?

Where flow rates are less than 5.0 l/s consent for discharge isusually set at 5.0 l/s if blockage from vegetation and othermaterials is possible. Lower consent flow rates may be set wherethe blockage risk is addressed by using appropriate drainageelements.

(3) Is SPR/SPRHOST ≤ 0.3?

Where groundwater levels are low enough the use of soakawaysto avoid discharge offsite would normally be preferred fordisposal of surface water runoff.

Greenfield runoff ratesDefault Edited

Q (l/s): 6.17 6.171 in 1 year (l/s): 5.24 5.241 in 30 years (l/s): 14.19 14.191 in 100 year (l/s): 19.68 19.681 in 200 years (l/s): 23.08 23.08This report was produced using the greenfield runoff tool developed by HR Wallingford and available at www.uksuds.com. The use of this tool is subject to the UK SuDS terms and conditions andlicence agreement , which can both be found at www.uksuds.com/terms-and-conditions.htm. The outputs from this tool are estimates of greenfield runoff rates. The use of these results is theresponsibility of the users of this tool. No liability will be accepted by HR Wallingford, the Environment Agency, CEH, Hydrosolutions or any other organisation for the use of this data in the design oroperational characteristics of any drainage scheme.

BAR

BAR

BAR

BAR


Appendix F – Quick Storage Estimate Calculations

Quick Storage Estimate


Appendix G – Southern Water Asset Record

The positions of pipes shown on this plan are believed to be correct, but Southern Water Services Ltd accept no responsibility in the event of inaccuracy. The actual positions should be determined on site. This plan is produced by Southern Water Services Ltd (c) Crown copyright and database rights 2021 Ordnance Survey 100031673 .This map is to be used for the purposes of viewing the location of Southern Water plant only. Any other uses of the map data or further copies is not permitted.

WARNING: BAC pipes are constructed of Bonded Asbestos Cement.

WARNING: Unknown (UNK) materials may include Bonded Asbestos Cement.

Date: 15/06/21 Scale: 1:1250 Data updated: 17/05/21Map Centre: 578270,144484(c) Crown copyright and database rights 2021 Ordnance Survey 100031673 Wastewater Plan A1Our Ref: 578937 - 1

Staplehurst

[email protected]

Manhole Reference Liquid Type Cover Level Invert Level Depth to Invert

0501 F 25.87 24.52

0502 F 22.72 21.15

1200 F 25.61 23.30

1501 F 22.34 20.84

1502 F 21.87 20.46

1503 F 21.85 20.78

2201 F 25.36 23.02

2202 F 24.95 22.55

2501 F 21.12 19.92

3101 F 24.93 23.62

3201 F 24.48 22.12

3203 F 24.13 21.51

3204 F 24.33 23.02

3501 F 20.54 19.37

3502 F 20.12 18.87

4102 F 23.57 0.00

4301 F 22.59 20.44

4302 F 22.85 20.21

4303 F 22.57 20.09

4304 F 23.30 21.02

4401 F 21.48 20.70

4601 F 19.87 18.58

5101 F 22.50 20.23

5201 F 22.37 20.62

5202 F 21.89 20.05

5203 F 21.84 19.87

5301 F 21.86 19.55

5302 F 21.87 19.23

5303 F 21.36 19.00

5501 F 19.18 17.62

5601 F 21.82 19.83

5602 F 19.92 0.00

5700 F 23.52 21.67

6103 F 21.25 19.64

6201 F 22.77 22.13

6202 F 21.13 20.34

6203 F 20.64 0.00

6204 F 20.92 19.44

6205 F 20.89 18.86

6206 F 20.62 19.35

6207 F 20.68 19.32

6208 F 20.55 19.18

6209 F 20.54 19.14

6210 F 20.50 18.54

6301 F 20.94 18.72

6501 F 19.05 17.35

7104 F 21.11 19.25

7105 F 20.96 19.25

7106 F 20.88 19.01

7107 F 21.37 19.97

7108 F 21.11 19.82

7109 F 21.20 19.69

7201 F 20.88 19.15

7202 F 20.88 18.89

7203 F 20.74 18.59

7204 F 20.37 18.46

7205 F 20.27 18.30

7208 F 20.11 17.48

7209 F 20.46 19.38

7210 F 0.00 0.00

7301 F 20.59 18.16

7307 F 0.00 0.00

7308 F 0.00 0.00

7501 F 18.59 17.04

1250 S 25.64 23.50

2250 S 25.25 23.22

3250 S 24.80 23.11

3251 S 23.96 22.39

3252 S 24.45 22.68

3350 S 23.37 22.06

4350 S 22.75 21.66

4351 S 22.47 21.33

5250 S 21.54 20.48

5251 S 21.67 20.40

5252 S 21.85 20.04

5253 S 21.82 19.94

5254 S 21.78 19.69

5255 S 21.43 19.38

5256 S 22.32 20.88

5257 S 21.76 20.08

5258 S 21.92 20.06

5259 S 22.16 20.66

5260 S 21.83 20.82

6250 S 21.21 19.22

6251 S 20.93 19.20

6252 S 20.81 19.07

6253 S 20.79 18.99






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