An overflowing manhole has caused a 'sewage river' that is flowing towards a children's play area.
The leak, near Maidstone Leisure Centre in Mote Park, has caused a stream of waste to flow down the road and onto the grass.
A giant puddle has also formed causing the pathway into the main park to be taped off from either side.
The waste is running down in the direction of a new adventure park, which is to be officially opened on Thursday.
A resident of Birchtree Way, who made the discovery whilst walking his dogs this morning, said he was ankle deep in the human waste.
The man who did not want to be named said: "It is appalling. There is fluid all over the floor and it has gone up to my ankles.
"It is trickling down near the play area like some kind of sewage river.
"You can smell it from ages away and there children playing right next to it."
The site was used at the weekend for the Ramblin Man fair event, which saw thousands of visitors attend.
He added: "I went to Ramblin Man and there were no issues with the sewage systems.
"This has been happening for years, it is disgusting."
People were warned to stay away from the water and all water sports activities were cancelled whilst repairs were made in May last year.
A Southern Water spokesman said: “We were alerted to overflowing manholes close to Maidstone Leisure Centre this morning.
"Our team is currently investigating the cause and is also putting in place measures to prevent the overflow from draining into the lake.
"We will be liaising with the Environment Agency to ensure that our plans will protect the environment.”
Despite already being open, the new adventure playground is set to have an official opening on Thursday.
The council is spending a total of £4.3million on improvement works at the park.
This will include the playground, a visitors centre, a cafe and new toilets.
A council spokeswoman said: "Maidstone Borough Council is aware of an issue with a mains sewer pipe near to the Leisure Centre car park – adjacent to Mote Park. The pipe appears to be blocked with sewage waste leaking on to the car park.
"Representatives of Southern Water (who are responsible for the sewage pipe and drains), and the MBC Parks Team are currently on site investigating the issue to prevent this happening again, while working towards an environmental clean-up of the entire area.
"Please be assured that the leak is external to the Maidstone Leisure Centre building and isn’t affecting operations, service or any of the activities taking place at the centre.
"We apologise for any inconvenience caused and we are working as quickly as we can to clean-up the area."
The Environment Agency has said they are aware of the issue and are investigating the matter with Southern Water.