Columbus City Utilities has found the source of an e-coli contamination that polluted one of the city’s drinking water wells last month and led to a city-wide boil water advisory. Keith Reeves, the city’s utilities director, says that corrosion in the well casing has left small holes in the tainted well near the Bartholomew County 4-Fairgrounds, allowing contaminants into the water. He said that a contractor inspected the affected well with a camera and discovered the corrosion about 20-25 feet down the well shaft. Reeves said that the well has been taken off line until the problem is fixed. He said that officials are still figuring out the scope of the repairs but estimated it could run up to $20,000.

The city declared its first citywide boil water advisory last month in almost two decades after testing revealed the contamination. The Utilities Service Board met Thursday and heard an update from Reeves on fixes to be made to the notification process, should this occur again.