Government has confirmed over 140 fish have died following a pollution incident at Summerhill Glen.
The incident was first discovered by a Manx Wildlife Trust officer yesterday - the Department of Environment, Food & Agriculture then carried out water checks and have been investigating the matter.
Now, officials say 143 fish, including brown trout and sticklebacks, have died as a result and have identified the first signs of the problem came from an area called 'The Nook'.
They add it could mean the fish population may take several years to recover.
As a result, DEFA Minister, Geoffrey Boot MHK, is now asking residents to watch what they dispose of down their drains as the impact of such pollution can be 'devastating' on aquatic life.
If you have any concerns about what may be entering surface water drains or watercourses in your community, you're asked to contact the Environmental Protection Team on 685 885 or Fisheries on 685 857.