Development and Flood Risk - the Environment Agency s approach to PPS25. scrutinised before planning decisions are made

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1 Development and Flood Risk - the Environment Agency s approach to PPS25 Steve Cook Flood Risk Policy Advisor Stephen.cook@environment-agency.gov.uk Our role in PPS25 h Providing advice and information h Advising on flood risk assessments scope, methods and commenting on results h Consultee on spatial plans and their sustainability appraisals h Consultee for most planning applications in flood risk areas h Having a Call In Direction - to ensure flooding has been fully scrutinised before planning decisions are made Steve Cook Environment Agency 1

2 Flood Risk Management Flood Risk Model Source (River or sea) Pathway (defended or not) Receptor (Flood plain) Risk = Probability x Consequence Source and Pathway contribute to probability Impact on Receptor contributes to consequence Steve Cook Environment Agency 2

3 Flooding from ALL sources Fluvial Coastal Pluvial (surface water) Ground water Overland flows Sewers & drainage systems Reservoirs, lakes, canals The PPS25 approach PPS25 FLOOD RISK MANAGEMENT HIERARCHY Step 1 Step 2 Step 3 Step 4 Step 5 Assess Avoid Substitute Control Mitigate Appropriate flood risk assessment Apply the Sequential approach Apply the Sequential test at site level SUDS, Design, flood defences Flood resilient construction Steve Cook Environment Agency 3

4 Appraising Flood Risk EA Flood Maps EA s National Assessment 2006 Three tiers of Flood Risk Assessment h Regional (RFRA) Rngl Assembly h Strategic (SFRA) LPA/Developer h Site-specific (FRA) - Developer Purpose of a SFRA To identify: h For all flood zones - the areas within a development plan that are at risk of flooding h Within flood zone 3 - the variations in the actual flood risk including the effect of any defences h For all zones - the effects of surface water run off from proposed developments and any areas where the receiving system is known to be inadequate Steve Cook Environment Agency 4

5 The Do s and Don ts Do s Start as early as possible Contact the EA before starting Ensure geographical scope suitable for the sequential test Consider all sources of flooding Consider current and future flood risk likelihood and consequences Use it to inform policies and land use planning decisions Don t Assume a standard format and cost for all SFRAs Use a SFRA to justify preconceived land allocations and housing targets. Assume that the EA will produce an SFRA for you or has all the information. Assume one s not needed if there s no history of flooding Flood Map Steve Cook Environment Agency 5

6 SFRA map of residual risk High risk: Significant depth Medium risk High risk: Rapid Inundation Zone Low risk: island Outcomes Maps showing spatial variation of flood risk Evidence of sequential approach Sources, frequency and behaviour of flooding Surface water management issues Current and future flood risk Recommendations on land use and management Knock on effects on flood risk elsewhere Residual flood risk after mitigation Steve Cook Environment Agency 6

7 The PPS25 approach PPS25 FLOOD RISK MANAGEMENT HIERARCHY Step 1 Step 2 Step 3 Step 4 Step 5 Assess Appropriate flood risk assessment Avoid Apply the Sequential approach Substitute Apply the Sequential test at site level Control SUDS, Design, flood defences Mitigate Flood resilient construction Flood risk and land use Steve Cook Environment Agency 7

8 Safe for the development s lifetime h Climate change must be factored into location and design decisions h We assume lifetime means: h 100 years for residential h Case-specific for commercial h House built in 2010 on South coast must be designed to be safe with a 1.05m sea level rise Safe within the building? Steve Cook Environment Agency 8

9 Safe access and exit Emergency services ability to evacuate or rescue people Steve Cook Environment Agency 9

10 During the flood: h Lights? h Heating? h Water? h Phones? Managing and reducing risk Steve Cook Environment Agency 10

11 Managing and reducing risk Dealing with uncertainty h Follow the sequential approach h If still in doubt, don t build there! h Design for exceedance h Design to reduce flood risk h Design for social and environmental enhancement Steve Cook Environment Agency 11

12 Useful sources of advice CLG & Defra publications & PPS25 Practice Guide CIRIA Environment Agency web site: h Developer s Guide h Flood maps & Standing Advice h Environmental Quality in Spatial Planning h SEA Good Practice Guidelines h What we re looking for on development and flood risk h People talk to us EARLY h That information sources have been utilised h Evidence of sequential and exception tests being correctly applied h An appropriate FRA with results influencing decisions h FRA demonstrates the development will: h be safe for the lifetime of the development h not increase flood risk elsewhere h deliver clear opportunities to reduce risk overall Steve Cook Environment Agency 12

13 Development and Flood Risk - the Environment Agency s approach to PPS25 Steve Cook Flood Risk Policy Advisor Stephen.cook@environment-agency.gov.uk Steve Cook Environment Agency 13