Flood risk

Surface water flood risk

Surface water flooding affects a large proportion of the District.  In recognition of this planning policy acknowledges this situation and various county and local standards have been adopted and apply, which can be viewed under Supplementary Requirements for Surface Water.

Villages within the catchments of the Aldingbourne and Lidsey Rifes are known to have long standing drainage and surface water.  As part of new evidence during the examination of the Local Plan consultants were employed to specifically look at these issues and proposes potential solutions both on and off-site to help address these issues.  The result of this work was the Strategic Surface Water Management Study:  Arun SSWMS Final Report.pdf [pdf] 34MB

 

SFRA Update 2016

This work was commissioned to update the Strategic Flood Risk Assessment for the District outside of the National Park.  This was necessary to support decisions around Main Modifications to the Arun Local Plan 2011-2031 during the period of suspension during the examination process.  Below is the SFRA Level 1 published in August 2016 and also a hybrid report incorporating Levels 1 & 2.  The hybrid report  sets out the current situation regarding flooding from differing sources across the District, supported by Appendices A - I, followed by a broad assessment of strategic sites/locations being considered by the Local Plan with more detailed assessments of the flood risk for each, contained in Appendix J. All maps in the Appendices are at a District level followed by a more detailed version split by the grids identified in Appendix A, apart from Appendix J.

2016s3756 - Arun District Council Level 1 SFRA - Final Report (v2 August 2016).pdf [pdf] 8MB 
2016s3756 - Arun District Council Level 1 and Level 2 SFRA (v5 September 2016).pdf [pdf] 9MB
2016s3756 - Arun District Council Final Combined Level 1 and Level 2 SFRA - Final Report (v5 November 2016).pdf [pdf] 9MB

SFRA Update 2016
Appendix A 2016s3756 - Appendix A - SFRA Appendix Mapping grids.pdf [pdf] 4MB
Appendix B 2016s3756 - Appendix B - Watercourses (A2 district).pdf [pdf] 11MB
Appendix B

2016s3756 - Appendix B - Watercourses (A3 tiles) part 1.pdf [pdf] 9MB 
2016s3756 - Appendix B - Watercourses (A3 tiles) part 2.pdf [pdf] 12MB  

Appendix C 2016s3756 - Appendix C - Flood Zones (A2 district).pdf [pdf] 11MB
Appendix C 2016s3756 - Appendix C - Flood Zones (A3 tiles).pdf [pdf] 12MB
Appendix D 2016s3756 - Appendix D - Climate Change (A2 district).pdf [pdf] 18MB
Appendix D 2016s3756 - Appendix D - Climate Change (A3 tiles) part 1.pdf [pdf] 9MB
2016s3756 - Appendix D - Climate Change (A3 tiles) part 2.pdf [pdf] 13MB
Appendix E 2016s3756 - Appendix E - Surface Water (A2 district).pdf [pdf] 12MB
Appendix E 2016s3756 - Appendix E - Surface Water (A3 tiles).pdf [pdf] 14MB
Appendix F 2016s3756 - Appendix F - Groundwater (A2 district).pdf [pdf] 10MB
Appendix F 2016s3756 - Appendix F - Groundwater (A3 tiles).pdf [pdf] 27MB
Appendix G 2016s3756 - Appendix G - FWAs (A2 district).pdf [pdf] 11MB
Appendix G

2016s3756 - Appendix G - Flood Warning Areas (A3 tiles) part 1.pdf [pdf] 8MB 
2016s3756 - Appendix G - Flood Warning Areas (A3 tiles) part 2.pdf [pdf] 11MB  

Appendix H 2016s3756 - Appendix H - Historic Flooding Records (A2 district).pdf [pdf] 10MB
Appendix H 2016s3756 - Appendix H - Historic Flooding Records (A3 tiles).pdf [pdf] 28MB
Appendix I 2016s3756 - Appendix I - Defences (A2 district).pdf [pdf] 10MB
Appendix I 2016s3756 - Appendix I - Defences (A3 tiles).pdf [pdf] 28MB
Appendix J 2016s3756 - Appendix J - Level 2 SFRA site summary sheets.pdf [pdf] 13MB

 

Strategic Flood Risk Assessment (2008)

Arun District Council commissioned consultants, Capita Symonds, to undertake a Strategic Flood Risk Assessment (SFRA) of the District which will support planning decisions and help inform the production of the Council's Local Development Framework.

The main objective of the Arun District SFRA is to provide flood risk information:

  • so that an evidence based and risk based sequential approach can be adopted when making planning decisions, in line with PPS25;
  • that is strategic, in that it covers a wide spatial area and looks at flood risk today an in the future;
  • that supports sustainability appraisals of the local development frameworks;
  • that identifies what further investigations may be required in flood risk assessments for specific development proposals.

 

 

SFRA Box 1

Volume 1 User Guide.pdf [pdf] 1MB
Volume 2 Technical Report and Maps.pdf [pdf] 4MB
Volume 3 Management Guide.pdf [pdf] 492KB
Volume 4 Assessment of Sites of Search.pdf [pdf] 483KB

 

SFRA Box 2

A1 - F Actual and residual risk of flooding from rivers.pdf [pdf] 4MB
A1 - T Actual and residual flooding from the sea.pdf [pdf] 4MB
A2 - F Flood Depth - Actual risk of flooding from rivers.pdf [pdf] 4MB
A2 - T Actual and residual flooding from the sea.pdf [pdf] 4MB
A3 - F Flood Velocity - Actual risk of flooding from rivers.pdf [pdf] 4MB
A3 - T Flood Velocity - Actual risk of flooding from sea.pdf [pdf] 4MB
B Residual risk from breach.pdf [pdf] 4MB
C1 - F Actual river climate change extents (with defences).pdf [pdf] 4MB
C1 - T Actual sea climate change extents (with defences).pdf [pdf] 4MB
C2 - F Climate Change Fluvial Flood Zones.pdf [pdf] 4MB

SFRA Box 3

C2 - T Tidal Flood Zones with Climate Change.pdf [pdf] 16MB
D1 System Asset Management Plan Areas.pdf [pdf] 14MB
D2 Types of Flood Defence.pdf [pdf] 13MB
D3 Source of Flooding Being Defended.pdf [pdf] 14MB
D4 Estimated Standard of Protection.pdf [pdf] 13MB
F1 - F Fluvial Flood Zone Extents.pdf [pdf] 14MB
F1 - T Tidal Flood Zone Extents.pdf [pdf] 14MB
F2 - F Source of River Flood Zone 3a Data (No Defence).pdf [pdf] 15MB
F2 - T Source of Tidal Flood Zone 3a Data (No Defence).pdf [pdf] 15MB
G1 Indicative Risk of Groundwater Flooding.pdf [pdf] 30MB

 

SFRA Box 4

H Historic Flood Events.pdf [pdf] 14MB
L Areas Prone to Flooding From The Land.pdf [pdf] 27MB
M1 Flood Management Plans and Strategies.pdf [pdf] 13MB
M2 Flood Management Policies.pdf [pdf] 28MB
M3 Models Used In SFRA.pdf [pdf] 17MB
O Overview of Arun District Council SFRA Study Area.pdf [pdf] 13MB
S Historic Incidents of Flooding From Sewers.pdf [pdf] 13MB
T1 Source of Topographic Data.pdf [pdf] 20MB
T2 Ground Topography.pdf [pdf] 20MB
W1 Environment Agency Flood Warning Areas.pdf [pdf] 17MB

 

The Strategic Flood Risk Assessment (SFRA) for Arun and the Sequential Test, were carried out in 2008 and 2009.  Since then, a West Sussex wide SFRA was undertaken by consultants Capita Symonds, on behalf of West Sussex County Council, in 2010. Together, these documents form the evidence base relating to flood risk for the Arun District Draft Local Plan.

More information is held on West Sussex County Council's SFRA and Sequential Test page.

 

Sequential Exception Test (2014)

This document sets out the approach that has been taken to ensure that the Local Plan has been prepared taking account of flood risk, now and in the future. This paper has helped to inform the Sustainability Appraisal for the Local Plan. As the Local Plan has been progressed the sequential test, and where necessary the exceptions test, have been applied to inform site selection. The National Planning Policy Framework (NPPF) (2012) (paragraphs 93 to 108) sets out how Local Plans can help to the meet the challenge of climate change, flooding and coastal change.  Planning Practice Guidance (PPG) (2014) (paragraphs 019)  sets out how to plan new development taking account of flood risk using the “sequential approach”. Where there are no reasonably available sites, local planning authorities, in their decision making should take into account the flood risk vulnerability of land uses and consider reasonably available sites, applying the “exceptions test” only in circumstances where insufficient land is available in the lower risk extents. This is one part of an integrated process that takes account of many factors, including wider sustainability issues, the realism of site delivery and in response to consultation with the public, business and partner agencies.

Arun Local Plan (2011 – 2031) Sequential Exception Test 2014.pdf [pdf] 189KB

During the suspension period of the Arun Local Plan 2011-2031 examination, further work relating to flood risk was done.  As a result of this and due to challenge over the content of the 2014 submitted document, a new document was produced to inform Main Modifications.  This reflects the latest information from the new evidence documents, such as any changes to flood extents and as much detail as possible regarding expected delivery.

Seq-Exception.pdf [pdf] 4MB and Seq-Exception Appendix.xlsx [xlsx] 16MB

 

Sequential and Exception Test (2009)

PPS25: Sequential and Exception Test for the Arun District Core Strategy

The Sequential and Exception Test has been prepared for the Core Strategy in line with Planning Policy Statement 25: Development and Flood Risk. The sequential test is a simple decision making tool to ensure sites at little or no risk of flooding are developed in preference to areas at high risk of flooding. It informs the Core Strategy, which will form a key part of the Arun District Local Development Framework.

Arun Sequential and Exception Test.pdf [pdf] 151KB