A litter-filled lake almost flooded with excrement has been given the all clear – but a dog walker fears it is still contaminated.

It is understood the sewage hatch near the water in Gordon Gardens at Riverside Leisure Area in Gravesend exploded on April 7 after some flash flooding and almost seeped into the lake.

Tony Loveridge, who walks his dog around the park every morning and evening, has raised concerns that the water is still contaminated with excrement.

He said: "My issue is not with the water but what is floating on top. You can see from the colour of it, it is brown and frothy. The stench is disgusting.

"I just feel something needs to be done about it. I know they cannot empty the lake but leaving it as it is I cannot understand."

But a spokesman for Gravesham council confirmed that although there was an incident earlier this year, it was dealt with at the time and water tests have confirmed there is no waste present in the lake.

He said: "The original incident when the sewer breached the side mound of the locked inspection hatch to the southwest of the lake in Gordon Gardens happened at approximately 5am. We had contained and cordoned off the area by 7.30am that same morning.

"The majority of the waste was contained on the banks and solid waste was captured in the run-off area before reaching the water’s edge.

"Our park rangers and cleansing team cleared the waste and debris from the banks and deep cleaned the area, preventing any contamination leeching into the water.

"Southern Water was notified and sent a team to repair the damage to their manhole and clean waste that we either could not reach or did not have the specialist tools required to clear. This was done in the days immediately after the incident and we are satisfied the area was fully cleaned and all waste that might be detrimental to wildlife removed.

"Subsequent laboratory testing of water from the lake as part of our ongoing management and monitoring of it has shown no trace of sewage waste in the lake.

"As part of our management programme, we have moved away from the use of herbicide on and around the lake and coupled with our policy of allowing only one pump to operate during the summer this has encouraged wildlife into the water, including seven different species of bird today alone."

Despite this, Tony, of Park Place, is still not convinced and wants an independent source to test the water.

The gardener added: "I think they need to test the froth. It is not going away whatever it is."

The 57-year-old has also noted a large amount of litter which has been thrown into the water including beer and vodka bottles, crisp packets, plastic bags and even a pair of handcuffs.

And he is not the only one who is concerned about the state of the lake. Regular walker Brian Palmer, 68, said: "There is a fair bit of litter in there I have noticed. It might be that the reeds are gone which was hiding it.

"I think it could be a little bit more maintained. They do maintain it but I think they need to get a boat and run around and pick it up. It would be nice to see the lake back as it was."

Susan Lyons who walks her dog around the park once a week said she has noticed the rubbish but does not think it is that significant.

"They try their best to tidy it but it is groups of people who make the difference," she said. "The council have done a lot but there is always room for improvement.

"I think they work really hard keeping it nice. Litter is always going to be an issue."

A spokesman for Gravesham council said the edge of the lake is litter picked every day but to clear the middle requires additional equipment which is done a little less frequently but is still a regular occurrence.