Flood Risk Assessments and Sustainable Urban Drainage systems

Planning Stage and Development Advice

Flood risk assessments (FRA) are commonly required as part of a planning stage condition particularly in low lying coastal regions or where surface water run-off from new and existing buildings is affected by development.

The National Planning Policy Framework (NPPF) sets out the Government’s planning policies for England and how these should be applied. It provides a framework within which locally prepared plans for housing and other development can be produced.

The Environment Agency identifies flood risks arising throughout England and provides a free service that offers a flood risk map of your area.  Flood risks are categorised from Flood zone 1 to Flood zone 3, with zone 1 being the lowest risk category and zone 3 being the highest. Generally, you do not need an FRA if you are in a zone 1 area and your development is less than 1 hectare, or the planning authority and the Environment Agency have identified critical drainage problems from surface water or groundwater that could lead to flooding.

Crofton offer many years of experience over many regions of the country and undertake the assessment to provide FRA reporting in accordance with the requirements of the NPPF.

We liaise with the project team to consider suitable construction levels to avoid managed flood water, and to consider other issues as may be raised by the Environment or Planning Authority to inform your project design and achieve compliance.

Sustainable Urban Drainage systems (SUDs) are now a very common requirement for any development.  A development will usually increase the amount of rainwater run-off – for example by increasing hard standing for car parking, or by the introduction of new buildings and associated run-off from roofs.  The sustainable solution seeks to manage the additional rainwater run-off without increasing the impact upon the existing rainwater disposal system and where possible, in a way that mimics natural features such as retention ponds.

Crofton are able to advise on a range of mitigation measures to arrive at a compliant design solution to meet water authority / Environment agency requirement.