Surface water should be managed as close to its source as possible. Landscape features should be used to manage, store, and slow the flow of water.

Any rates of discharge shall be restricted to the run-off set out in the National Standards for SuDS 2025 (or any replacement standards). Clear evidence of existing operational connections from the site with associated calculations on rates of discharge will be required to demonstrate reduction in discharge rates. Without evidence, discharge at greenfield run-off rate will be required.

Development should not result in the loss of open watercourses including ponds; and culverts which should be opened. The culverting of existing open watercourses will not be permitted without evidence of an overriding need to do so.

SuDS should be designed to avoid adverse impacts on water quality and any possibility of discharging hazardous substances to or below ground. They should be integrated with green infrastructure to provide climate resilience, biodiversity and amenity benefits.

Long-term maintenance arrangements for SuDS must be secured through planning conditions or legal agreements to ensure functionality for the lifetime of the development.

Stockport is one of the highest flood risk regions in the North West of England from surface water and sewer flooding and as such the entirety of the borough has been assessed to be a Critical Drainage Area. Stockport lies in a relatively low-lying area in three main flat valleys that has many associated watercourses with flood risk. It is a heavily and densely populated area with a significant level of infrastructure. Watercourses have traditionally been culverted so that land can have an alternative use. This creep effect has continued to bury assets and restricted natural surface water run-off causing higher ground water problems.

National policy relating to flood risk is set out in the NPPF. It requires Local Planning Authorities to adopt proactive strategies to mitigate and adapt to climate change, taking full account of the long-term implications for flood risk and water supply etc. It also states that policies should support future resilience of communities and infrastructure to climate change.

Under the Flood and Water Management Act (2010) we became a Lead Local Flood Authority (LLFA). We are responsible for managing local flood risk from surface water, ground water and ordinary watercourses in Stockport. One of the duties placed upon us is to assist in the management of local flood risks. The LLFA is to ‘develop, maintain, apply and monitor a Local Flood Risk Management