Dog owners say leaks from a treatment works are stopping them from letting their pets near a nature reserve and beach.

Visitors to Swalecliffe Brook have told KentOnline how sewage and diesel spills from the nearby Southern Water facility mean their dogs cannot use the Brook or Swalecliffe beach.

One dog owner claims their pet was ill after it went into the water.

Residents nearby also complain about the smell of sewage in their gardens and their homes. It follows a diesel leak last Wednesday at the Brook, which is being investigated by the Environment Agency (EA).

Couple John and Andrena Wilkes describe how the “filthy” water from the Brook - which can reach the sea on some days - means they cannot let their dog, Alfie, enjoy himself on the beach.

Mrs Wilkes, 55, said: “During the summer, this is the only section of the beach which you can take your dogs into - but we can’t take him in there because of the sewage.

“Sometimes I have let him go in because I have checked it. But often he would quite like to go in but he can’t. That’s why we walk him on the path and not on the beach because he would go straight in the water.”

Mr Wilkes, 65, claims it affects people going into the water too. But he said: “Some people go in but they probably don’t know about it.”

Michelle Halford, 50, who walks her six dogs at the Brook, says one of her pets ran into the Brook following the diesel leak.

She said: “I woke up and she was really poorly. You can’t say to a dog, ‘please don’t run over there’.”

Ms Halford says her dogs have run into the Brook before and come out smelling of “sewage”.

“Even one wash doesn’t get the smell off,” she said.

Residents who live in Swalecliffe say they are also forced to shut their windows during the summer because of the smell of sewage.

Lyn Edenborough, 71, said: “It’s disgusting. It makes you feel embarrassed about having guests around. We have to close the windows on a bad day.”

Kieran Monk, 26, added: “Some mornings you wake up and it is all you can smell - it makes you feel quite sick. It makes me feel quite angry. We all pay our water bills and we get this.

“It is holiday season and people can’t go into the sea.”

People were warned not to enter Swalecliffe Brook last week, or let their pets go in, following the diesel leak on Wednesday.

Residents reported the 300-metre slick to the EA, which is now investigating.

A Southern Water spokesman said: “Investigations into a diesel leak from our wastewater treatment works at Swalecliffe, and a full scale clean-up of the local brook are ongoing.

“We know this may be an inconvenience to dog walkers and other beach users and we’re sorry about this, but we are working as quickly and as safely as possible with specialist teams to carry out a full clean-up operation.

“Some mornings you wake up and it is all you can smell - it makes you feel quite sick..." Kieran Monk

“Protecting the environment is our priority, and so we’re also working with Natural England, who are helping us to ensure the clean-up has a minimal impact on the area. We’re also liaising with the council, which has put up signs advising people not to go into the water. We thank everyone for their patience as we carry out these emergency works.”

The EA said the oil slick had reached as far as the beach.

A spokesman said: “We dispatched our Environmental Incident Vehicle and five officers to deploy pollution prevention measures which included booms, bungs and oil absorbent pads.

“Subsequently, we’ve identified the source of the pollution and stopped any further diesel entering the Swalecliffe Brook.”

Canterbury City Council put signs up to advise people not to enter the water or to let their pets go in either.

Diane Comley, Kentish Stour Countryside Partnership officer, said: “Swalecliffe Brook is a habitat for many species, including a vulnerable population of water vole - a declining species in the UK.

“The lower reach is the intertidal zone at Long Rock, is part of a designated Site of Special Scientific Interest, a habitat that supports many specialist species including water fowl that may be negatively affected.”

Hundreds of fish were killed in 2013 following a sewage leak at the Brook, which landed Southern Water with a £500,000 fine.

In June, the firm agreed to pay £126 million in penalties and payments to customers following serious failures in the operation of its sewage treatment sites and for deliberately misreporting its performance.

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