Wessex Water and The Environment Agency have confirmed that sewage was discharged into the river Avon on Monday (31st October).
The leak happened following a blocked sewer burst.
Fortunately, the area affected had already been cleared of fish for the construction of the River Park project, and the pollution clear up began quickly.
The Environment Agency has had staff on site monitoring the clear-up work, which has meant a suspension of the River Park project work.
Salisbury's MP, John Glen, said in a tweet: "I am extremely disappointed by the news that sewage has made its way into the River Avon following a burst and blocked sewer. I urge @wessexwater to work with the @EnvAgency to act quickly in preventing the spill from further infecting our water ways."
There has been no confirmation about how long the delays to the River Park project will last. The project is being run by Wiltshire Council and The Environment Agency and is designed to help prevent future flooding in Salisbury.

The Barber Academy Celebrates Ten Years
The International Salisbury Pancake Race Returns for 2026
Bishop of Salisbury to Commission Eight Volunteer Chaplains for the LGBTQIA+ Community
Tri-County Summit Boosts Joint Effort to Tackle Rural Crime
Local Voices Reveal Gaps and Solutions in Dementia Support
Rock and Roll Man Interviews: Part 3 - Julian Bird & Gary Turner
The Spitfire Café Brings Family Fun to Cross Keys This February Half Term
Local RNLI branch seeks more volunteers
