Collection

Storm overflows

Information on storm overflow management and regulation.

• From: Department for Environment, Food & Rural Affairs
• Published: 11 December 2025

Storm overflows are an automatic relief mechanism for the sewer network. When the network is overwhelmed, they discharge excess rainwater and wastewater into England’s waterbodies.

You may also be interested in the: 

• Ofwat investigation into sewage treatment works and networks  

• Environment Agency investigation into sewage treatment works

Storm overflows discharge reduction plan

The storm overflows discharge reduction plan set stringent targets to protect people and the environment.

• Storm overflows discharge reduction plan
  • 25 September 2023
  • Policy paper

Discharge reduction plan progress report

An update on progress on implementing the storm overflows discharge reduction plan, and the effect of that progress.

• Storm overflows discharge reduction plan: progress report
  • 11 December 2025
  • Policy paper

Policy and guidance

Advice to the sector and regulators on the management and regulation of storm overflows.

• Storm overflows: policy and guidance
  • 24 March 2025
  • Guidance

Assessment and reports

How to assess the performance of and scope out improvements to storm overflows under Urban Waste Water Treatment Regulations requirements.

• Storm overflow assessment framework 2025
  • 24 March 2025
  • Guidance

Permits

How to: 

• control intermittent storm discharges from combined sewer overflows and waste water treatment works 

• minimise the risk of emergency sewage discharges from sewage pumping stations

• Water companies: environmental permits for storm overflows and emergency overflows
  • 13 September 2018
  • Guidance

Published 11 December 2025