flood risk assessments - spp7 compliant

Flood Risk

Flood Risk Assessments

 

Scottish legislation requires a Flood Risk Assessment be produced for all developments located within an identified flood risk area. A number of advice notes and legislation exist regarding development and flooding in Scotland:

  • Scottish Planning Policy (Sections 196 to 211). 

  • Planning and Building Standards: Advice on Standards (PAN69).

  • Technical Flood Risk Guidance for Stakeholders, Version 6.

Many parts of Scotland have a legacy of development at risk of flooding from watercourses, the sea, groundwater and inadequate drainage. Climate change is predicted to worsen the situation. The Scottish Environment Protection Authority (SEPA) currently provides indicative flood risk maps as a basis for identifying flood risk areas arising from fluvial and tidal sources.

The Scottish Executive's National Flooding Framework addresses the problems of flooding through 4 areas of action: Awareness, Assistance, Avoidance and Alleviation. It expects developers and planning authorities to err on the side of caution in decision making whenever flooding is an issue.

The requirements for a Flood Risk Assessment are set out in the Scottish Planning Policy. Certain development constraints apply to the different flood risk areas describe in the SPP Risk Framework:

 

Little or No Risk
Annual probability of watercourse, tidal or coastal flooding is less than 0.1% (1 in 1000 yr).

  • No development constraints exist due to watercourse, tidal or coastal flooding and so a flood risk assessment is unlikely to be required. 
 

Low to Medium Risk
Annual probability of watercourse, tidal or coastal flooding in the range 0.1% - 0.5% (1 in 1000 yr – 1 in 200 yr).

  • A flood risk assessment may be required at the upper end of the probability range (i.e. close to 0.5%) or where the nature of the development , or local circumstances, indicate heightened risk.

  • Water resistance materials and construction may be required depending on the outcome of the flood risk assessment.
 

Medium to High Risk
Annual probability of watercourse, tidal or coastal flooding greater than 0.5% (1 in 200 yr).

  • A flood risk assessment will be required to investigate potential flood depths on the development site. 

  • If development is permitted, appropriate measures to manage flood risk will be required and the loss of flood storage capacity mitigated to produce a neutral or better outcome. Land raising may be acceptable.

  • Water resistant materials and construction should be used where appropriate.
 

Waterco have an extensive experience of completing Flood Risk Assessments (FRA). Our knowledge and network amongst the relevant authorities have enabled us to produce over 100 reports in the last 5 years.  Feel free to contact our team for an informal discussion.

For information on flood risk and the SPP can be found in Flood Risk Guidance