Hundreds of people have continued to flock to a toxic pool at a former quarry despite repeated calls for them to stay away.
The water at Hoffman Quarry in Derbyshire has been dyed black from its usual bright blue colour, in an attempt to put off visitors.
Police compared the site to “Skegness in peak summer” and issued a number of parking tickets to visitors.
The fire service added one of its officers was abused by a swimmer.
The water at the site in Harpur Hill – dubbed the Blue Lagoon – is said to have “the same pH value as bleach”.
It has been dyed black to make it appear “less attractive” after warnings for people to avoid the site were ignored last week.
Councillor Keith Savage, from High Peak Borough Council, said he called the quarry water the “poison pond”.
He said: “It’s not a lagoon – its waste water from an old, disused quarry.”
Authorities said “no waiting” cones were also put up on local streets to deter visitor parking and PCSOs were present to support residents.
Despite these steps, Derbyshire’s roads policing unit said: “The blue lagoon and surrounding area is still like Skegness in peak summer.”
Mr Savage said about 2,000 people a day were visiting the site, making life difficult for nearby residents who were trying to social distance.
He said some visitors were also “urinating in people’s gardens” because there were not any public toilets.
Derbyshire Police told BBC North West the site had seen visitors from as far away as Cornwall.
On Friday, a person was seen swimming in the newly-dyed water.
Derbyshire Fire and Rescue Service said the swimmer abused one of their officers after they tried to “warn him of danger”.
Kev Page, from Derbyshire Fire and Rescue Service, told BBC Radio Derby: “We have got a physical presence here at the quarry to try to deter and educate people.
“Sadly we can’t enforce that people do not go up there.”
David Whelan, also from the service, said the site was “pretty horrible” with discarded litter and broken glass on the ground.
“The 10,000 people that have visited over the last few days have really left their mark and it’s going to take a lot of clearing up,” he added.