PFRA Guidance - Preliminary Flood Risk Assessments
What must I do?
The Flood Risk Regulations 2009, which implement the EU Floods Directive in England and Wales, require Lead Local Flood Authorities (LLFAs) to prepare Preliminary Flood Risk Assessments (PFRA) and identify flood risk areas by the end of June 2011.
What is a PFRA?
A PFRA is a high level assessment of flood risk, based on collecting existing information on both historical floods and future flood risk. For LLFAs, the focus of the PFRA should be on sources of flood risk for which they have responsibility, specifically surface water, groundwater and ordinary (non Main) watercourses.
How do I prepare a PFRA?
Your Preliminary Flood Risk Assessment should be based on existing, available information. To prepare your PFRA you will therefore need to collate information from a number of sources.
These might include:
- Environment Agency (EA) Flood Maps for Surface Water, which were published in early December 2010.
- Regional and Strategic Flood Risk Assessments (SFRAs).
- Historical records held by LLFAs, EA and other organisations, such as district and / or parish councils (where they exist), the highway authority, fire services, etc.
- British Hydrological Society records of historical events.
- Groundwater flood susceptibility mapping from the British Geological Survey.
Once data has been collected, it is necessary to understand the quality of the data and to determine which data best represents flood risk within the LLFA area. A preliminary assessment report must be prepared by the end of June 2011. The PFRA will be reviewed by the Environment Agency for finalising before the end of 2011. This report will include maps showing historical and potential future flood risk.
Defra has provided guidance on implementing the procedures, the emphasis being on the Flood Risk Strategy that will need to be produced. LLFAs are advised to be prudent in identifying new areas of risk as this will have implications in the preparation of plans to mitigate flooding. Defra has now provided guidance on what they see as significant levels of risk.
What are the next steps?
The PFRA and identification of flood risk areas are the first two steps of four in developing a plan for management of local flood risk. The Flood Risk Regulations identify two further steps:
Step 3 - Preparation of flood hazard and flood risk maps by June 2013
Step 4 - Preparation of flood risk management plans by June 2015.
The PFRA process then starts again with refinements to the PFRA maps, and iterates on a six-yearly cycle.
How can Royal Haskoning help me?
Royal Haskoning can provide guidance and support to help you prepare your PFRA. We have extensive expertise across a number of fields that are relevant to the preparation of PFRAs, including:
Data collection - skills in consultation and contacts throughout the industry. We can help you identify who you should be speaking to and what questions you should be asking.
Data collation, analysis - We have extensive GIS expertise that can quickly and efficiently collate, analyse and map datasets.
Understanding data - Data collection alone is not adequate; it is also necessary to understand the quality of data, and to use flood risk management expertise to understand its significance.
Mapping - presenting information through GIS, identifying flood risk areas.
Reporting - review, preparing the documentation and support for potential discussions with EA who have to sign off the reports.
Policy implications - guiding and supporting your decision on whether or not to identify ares of significant flood risk.
Other services that we provide can support you through the later stages of satisfying the Flood Risk Regulations, including:
Flood hazard mapping - 1D and 2D modelling. We regularly provide these services to the Environment Agency through the Strategic Flood Risk Management Framework.
Understanding the hazards - We can analyse flood extents and determine impacts on residential property, establish numbers of people at risk from flooding, and calculate economic damages.
Understanding the causes of flooding. Our experts can help you to understand the nature of flood risk and the causes of the flooding problem.
Practical mitigation measures - We have expertise in looking at a range of mitigation measures, such as SuDS, flood defences and urban design.
Impacts of new development - We can provide you with guidance on development planning and development control issues, and on mitigating the effects of new development on flood risk.
Funding – We can provide advice on sources of funding.
We can also help you with emergency planning, including operational resilience and understanding potential impacts of flooding critical infrastructure.