Environment secretary Thérèse Coffey has instructed water companies to share their plans on reducing sewage pollution.

The Storm Overflows Discharge Reduction Plan, published last year, required water companies to deliver £65bn worth of infrastructure improvements over the next 25 years. Now they are being told to reveal details of what they plan to do.

They have also been told to expect fines of up to £250m for breaches – reports of this new upper limit being dropped were untrue, the environment secretary said – although a public consultation on water company fines will be held in the spring.

Thérèse Coffey said: “People are concerned about the impacts of sewage entering our rivers and seas and I am crystal clear that this is totally unacceptable.

“We need to be clear that this is not a new problem. Storm overflows have existed for over a century. The law has always allowed for discharges, subject to regulation. That is how our Victorian sewers are built – wastewater and rain are carried in the same pipe. When it reaches a certain height, it pours into another pipe and into rivers.

“And while we have done more about it than any other government – we were the first government to require companies to start comprehensively monitoring spillage so that we could see what was actually going on – there is still significant work to do.

“I am now demanding every company to come back to me with a clear plan for what they are doing on every storm overflow, prioritising those near sites where people swim and our most precious habitats.”

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