A UK water company is working with local councils and members of the public to find environmentally friendly ways to prevent coastal sewage spills.
A new report published by Southern Water's Storm Overflow Task Force, explains why there are coastal storm releases and how working together can significantly reduce them.
In 2021 the water company was fined £90 million for releasing untreated wastewater into the environment between 2010 and 2015.
Storm overflow releases occur primarily due to the UK's predominantly combined sewer system, which means both wastewater and rain runoff enter the same network. During heavy downpours, rain overloads the system.
To avoid homes, businesses, schools and roads flooding, excess water is released into the sea - while the releases are around 95% rainwater they have not been subject to the full wastewater treatment process.
"While Southern Water is rightly investing significantly in improvements to their infrastructure, we all have a role to play.”
The report explores a number of innovative and traditional solutions ways to reduce these releases into the marine environment, including:
- Removing and slowing the flow of rainwater in the network through tree planting and creating rain gardens in schools
- Making better use of the existing infrastructure
- Removing impermeable surface
- Creating sustainable drainage in parks
- Diverting rainwater to the environment
- Investing in new assets
The water company, which is based in south-east England, is working closely with councils across its region, including Thanet District Council in Kent, to find collaborative solutions to these issues.
Dr Nick Mills, head of Southern Water’s Storm Overflow Task Force said, “What we ask of our partners and the community is to continue to support that journey, with photos and data, ideas and enthusiasm so that together we can agree how decisions can be made, now and in the future for the benefit of our environment.”
“What we ask of our partners and the community is to continue to support that journey ... so that together we can agree how decisions can be made ... for the benefit of our environment.”
Councillor Ash Ashbee, leader of Thanet District Council said, "While Southern Water is rightly investing significantly in improvements to their infrastructure, we all have a role to play. The district council will be working closely with the water company, and the local community, to collectively tackle this issue.”
Modern urban wastewater infrastructure was developed by in the UK in the 19th century, when Victorian engineers built a comprehensive system of sewers in London to pump all wastewater downriver.
Then in the early 20th century, engineers in Manchester invented a wastewater treatment process to clean the sewage before it was released into the environment, but it was not until the second half of the century that most high-income cities implemented these types of technology in large-scale treatment plants.
Sadly, many middle- and low-income cities worldwide lack these systems, leaving huge quantities of sewage untreated.
The public health and environmental gains of a robust and functioning wastewater treatment system have been game-changing but when the system fails - for whatever reason - it can pose a significant risk of public health and ecological disasters.
Southern Water's approach looks at a number of cost-effective and sustainable solutions and aims to move away from falling back onto carbon-intensive and expensive infrastructure projects, which can take years to complete and impact on local environment and communities in a number of ways.
Southern Water says preventing water from entering the combined sewer system during heavy rainfall is the most sustainable and cost-effective way to reduce storm overflows and not only are there are a variety of nature-based solutions to achieve this, such as ponds, wetlands, soakaways, and rain gardens, but that the public can help too by engaging with their water company.