SEWAGE was accidently spilled into a stream in Basingstoke after a leak was discovered by a member of the public.

Thames Water was informed of the emergency on Monday, after a walker noticed the treatment works in Whitmarsh Lane, near Chineham, were “pumping thousands of gallons of raw sewage into the local streams”.

Bradley Atkins, from Old Basing, told the Gazette: “There is a thick cake of sewage now choking the waterway.”

He contacted Thames Water on the emergency number and said someone came out to close the open pipe.

“This series of streams cuts through the popular public walks in the area, so it might be a good idea to warn locals about it,” he said, adding: “I suspect Thames Water’s idea of cleaning the streams will be to dump detergent into them. It smells like a sewer; it was coming out so fast.”

A spokesperson for Thames Water said the 750m stretch of Petty’s Brook will be cleared by today.

They added: “We responded to a report of sewage entering Petty’s Brook from a disused surface water sewer and immediately sealed it off to ensure all sewage flows are going into the correct system once more.

“We’re now conducting a thorough clean-up of Petty’s Brook, using sandbags to create a dam and a tanker to clear the water.

“We don’t expect any long-term impact and we’d like to assure residents there are no health and safety concerns in the surrounding area.”

Thames Water said the leak was caused by wastewater entering the wrong sewer, resulting in a drain needing to be sealed off.

The company said they do not know the exact volume of wastewater which entered the brook, but said it is thought to be “low”.

They asked residents and walkers to “be aware” of the tankers working in the area.