Corporate Responsibility

Surface water management.

Last reviewed:
We’re working in one of the most densely populated and urbanised regions in the UK, which places a lot of pressure on drainage. Without action, population growth, urban creep and climate change would increase the likelihood of sewer flooding and pollution. Historically our response has focussed on engineering solutions, typically using storage tanks, but we’re shifting our emphasis on reducing the volume of surface water entering our sewers with sustainable drainage systems (SuDS), creating capacity to manage future challenges in a more cost effective way.

Installing sustainable drainage in west London.

What are we doing?

We’re working with government, local authorities, organisations, charities and customers to raise awareness and make sure water is managed more sustainably. We share our data and expertise with local authorities and organisations, and contribute to local plans on surface water management plans. We continue to work with Defra, WaterUK and developers on the challenges facing SuDS, helping to raise awareness of sustainable water use, and managing the impact of new developments on our sewer network. We also use innovative software to explore SuDS opportunities across our region and contribute to the installation of SuDS schemes. Click on the case study below to find out more:

We are also continuing work to make sure our key operational sites can withstand and quickly recover from the impact of flooding caused by storms. We have developed river and rainfall flood risk maps to predict how storms could affect our sites, and to identify the increased risk presented by climate change.

In 2015, we launched a SuDS programme to disconnect 20 hectares* of impermeable land from the combined sewer network. We will be developing Drainage and Wastewater Management Plans to increase the scale and pace of this work, targeting areas with the least available capacity in the sewers. We have developed a programme to disconnect more than 65 hectares between 2020-2025 by:

  1. Providing up to £150,000 to each of the 93 local authorities with overall responsibility for surface water to contribute to SuDS schemes
  2. Forming partnerships with three Lead Local Flood Authorities with some of the greatest pressure on drainage capacity to jointly deliver a range of projects
  3. Funding third-sector bodies (including schools and environment groups) to deliver SuDS
  4. Installing a range of schemes ourselves in areas with the least available capacity in sewers, using large-scale SuDS and sewer interception / storage schemes
*One hectare is roughly the size of an international rugby pitch or the area inside a 400 metre athletics track.

What can you do?

  • Capture more rain - collect rainwater in tanks or water butts to use in your home and garden, reducing the amount of water taken from the tap.
  • Encourage natural drainage - allow rainwater to naturally soak into the ground with SuDS like soakaways, flower beds and permeable paving, all of which slow rainwater run-off and ease pressure on our sewer network.
  • Use less water - become more water efficient and reduce the amount of water you use, helping to save money and protect the environment.