100% of storm overflows across the water network in England have now been fitted with Event Duration Monitors (EDM).
EDMs increase transparency by measuring how, when and for how long a storm overflow is in operation.
This shows the public when discharges are happening, and helps the government and regulators to better hold water companies to account for illegal sewage spills and improve knowledge of overflow operation.
In 2010, 7% of storm overflows had monitors fitted. Now, with 100% oversight of overflows achieved, the government has delivered on part of its Plan for Water.
Storm overflows are an automatic safety valve that release excess pressure on the network from flooding and heavy rain – preventing sewage backing up into properties and stopping widespread mains pipe bursts across the country.
However, they should only be used under strict permit conditions and the government said the increased monitoring will give it and regulators the information needed to take action where permits are breached.
Environment Secretary Steve Barclay said:
“The completion of storm overflow monitoring is a major step forward in better protecting our precious waterways, as well as the communities and wildlife that rely on them.
“The wealth of data collected from these monitors will ensure that we know the full extent to the problem – increasing transparency, revealing the worst-offending overflows, and enabling regulators to hold polluters to account.
“This step is just one of many ambitious actions set out under our Plan for Water, which is delivering more investment, stronger regulation, and tougher enforcement across the water system.”
Illegal discharges
Environment Agency executive director John Leyland said every storm overflow being monitored will give the Environment Agency “much more information” about where and when storm overflow discharges are happening.
“This increased transparency will allow the Environment Agency to better tackle illegal discharges from storm overflows. We are dedicated to investigating those that breach their strict permitting conditions,” he said.
“We take our responsibility to protect the environment very seriously.
“We are also strengthening our regulation by expanding our specialised workforce, increasing compliance checks, and using new data and intelligence tools to inform our work.”
Water UK chief executive David Henderson said: “With 100% of the near 15,000 storm overflows across England now monitored we have the best, most comprehensive and accessible monitoring system in the world.
“This data will be invaluable in ensuring investment is targeted at those sites which urgently need improvements.
“Storm overflows are a design feature and act as a release valve after heavy storms. Water companies want them to operate as little as possible, which is why we are seeking regulatory approval to invest £11 billion over five years – three times the current rate – to increase the capacity of our sewers and prevent much more storm water entering the system in the first place.”
