Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, whether his Department has made an assessment of whether local authority decisions to grant applications to discharge drainage conditions attached to previously approved planning applications in relation to surface water drainage has contributed to flooding.

There are many factors that contribute to flooding, including but not limited to the built environment. National planning policy supported by planning practice guidance are the responsibility of the Ministry of Housing, Communities and Local Government in England. This enables the building of new homes and developments which are more resilient to flooding and ensures that there are clear safeguards for protecting people and property.

No development should take place until the developer has had approval, from the local planning authority, of a detailed sustainable surface water drainage scheme for the site. The drainage scheme shall demonstrate that any surface water (for all rainfall durations and intensities up to and including the climate change adjusted critical 100yr storm) can be accommodated and disposed of without discharging onto the highway and without increasing flood risk on or off-site.

These schemes can include the creation of Sustainable Drainage Systems (SuDS), which reduce the risk of surface water flooding, as well as delivering water quality, biodiversity and amenity benefits, helping to make great places to live.

Planning policy ensures that SuDS are provided in all new major developments, unless there is clear evidence that this would be inappropriate. This is in addition to requirements that SuDS should be given priority in new developments in flood risk areas. A 2018 review of the application and effectiveness of planning policy for sustainable drainage systems found that 87% of the sample of approved planning applications explicitly stated that SuDS would feature in the proposed development.

Under the Flood and Water Management Act 2010, Lead Local Flood Authorities (LLFAs) have responsibility for local flood risk management. This means ensuring risks of flooding from surface water, groundwater and ordinary watercourses, where this is no district council, are identified and managed as part of a local flood risk management strategy.

In managing these risks an LLFA will work closely with other Risk Management Authorities. This includes the local highways authorities, who are responsible for highway and gully maintenance and water companies who, under Section 94 of the Water Industry Act 1991, have a duty to maintain public sewers to ensure that their area is effectually drained.

When flooding occurs LLFAs investigate, to the extent that they consider it necessary or appropriate, which Risk Management Authorities have relevant flood risk management functions and whether they have exercised those functions. These are called Section 19 investigations because the duty is set out in Section 19 of the Flood and Water Management Act 2010. LLFAs must publish the results of the investigation and notify the relevant Risk Management Authorities.