On 18 December 2014, DCLG released a ministerial statement outlining that following on from a consultation period Lead Local Flood Authorities (LLFAs) would become statutory consultees on major planning applications.
The statutory instrument that brought the duty to respond to surface water drainage associated with major development into force, was laid before parliament in March 2015 with LLFAs commencing the duty on 15 April 2015.
Defra - non-statutory technical standards for sustainable drainage systems
To coincide with the statutory instrument, the Department for Environment, Food and Rural Affairs (Defra) released the Non-Statutory Technical Standards for Sustainable Drainage Systems. This document outlines standards for the design, maintenance and operation of sustainable drainage systems associated with both residential and commercial developments. This document is designed to be read in conjunction with the NPPF and PPG described below.
National Planning Policy Framework (NPPF)
The National Planning Policy Framework (NPPF) states in paragraphs 101-104 and 109 that when assessing planning applications, development should be directed away from areas at highest risk of flooding and must not increase flood risk elsewhere. Assessment of flood risk and water quality should be taken into account before applications are determined.
Planning practice guidance (PPG)
The NPPF is supported by Planning Practice Guidance (PPG) which provides a view on how the NPPF should be used in practice and is updated frequently. Guidance related to the preparation of Flood Risk Assessments (FRAs) can also be found in PPG.
To expand further on the documents detailed above, the Local Authority SuDs Officer Organisation (LASOO) produced practice guidance in 2016, giving further detail to the Non-statutory technical standards for SuDs. The LASOO guidance is referenced by many LLFA design guides.
Finally, a number of regional and local planning policies have been adopted or are being developed by individual districts and boroughs. These can offer advice on specific issues relating to flood risk and drainage and should be taken into account.