Campaigners say sewage in river is 'a horror'

Sewage was spilled into the River Ouse for nearly 600 hours in March

Campaigners have described the amount of untreated sewage that is being pumped into the River Ouse in East Sussex as "a horror".

There have been more hours of spills from one outfall known as Ham Lane, near Lewes, than any other storm overflow in the South East for three years running, according to figures released by Southern Water.

Last year it discharged for 4,824 hours and in 2025, in March alone, spills have lasted for nearly 600 hours - nearly 80% of the month.

Southern Water said the discharge was heavily diluted with groundwater that had entered the sewage network through joints in the pipework.

The sewage storm overflow in operation in dry weather

Matthew Bird, director of Love Our Ouse, said: "It's an absolute horror.

"To actually see it happening in what is one of the driest Marchs on record, it's really horrible."

Joff Edevane, from Southern Water, said: "Thirty years ago, people weren't so concerned, but now they rightly are.

"The Government storm overflow reduction plan has given us the kind of vehicle to get that put into our business plan so we can start addressing this problem."

The Ham Lane storm tank filled with diluted wastewater

The way the system is designed to operate is that a pumping station in Ham Lane should pump wastewater from Lewes to Newhaven for treatment.

However, if it is overwhelmed, it gets stored in a storm tank after screening.

If there is too much, it is sent directly from the tank into river.

In some areas Southern Water said it was solving the problem of leaky sewers by lining the pipes and added there were plans to do that in parts of Lewes too.

John Gower from the Friends of Lewes community group, who is a former environmental scientist at the Environment Agency, said: "We need to stop these discharges.

"They could build bigger storage tanks, but more importantly, they should increase the capacity of the pump and seal and repair the broken sewers that must be around.

"There are loads more houses being planned. They'll all have sewage that will go into the existing network.

"It can't cope at the moment on these nice dry sunny days. It doesn't seem right."

John Gower from Love Our Ouse at the scene of a discharge

Southern Water monitors all its storm overflows. The company records when and for how long a discharge is happening.

Permits are issued to water companies by the Environment Agency, which decides under what conditions storm overflows can be used.

The agency said they should not spill on dry days, but there are exceptions.

An Environment Agency spokesperson said: "Storm overflows, like Ham Lane, must only be used under strict permitted conditions that control their environmental impact.

"We will always seek to hold those responsible for environmental harm to account.

"If we identify illegal discharges from storm overflows, we investigate them, and action is taken in line with our Enforcement and Sanctions Policy."