The City of Hamilton says sewage has been leaking into the Hamilton Harbour in Lake Ontario for 26 years. 

The leak was discovered just after 12 p.m. on Tuesday by Hamilton Water maintenance staff, who uncovered a hole in a combined sewer pipe, spilling into a large storm sewer that was discharging into Hamilton Harbour. 

The staff believe the hole was put in the combined sewer pipe in 1996, over 25 years ago. 

According to the city's press release, staff are not currently aware of the exact volume of the discharge, but the city will publicly report this number as soon as staff assessments are complete. 

Today, the City of Hamilton provided an update related to an environmental and infrastructure issue. pic.twitter.com/D5RfH6WGKx

— City of Hamilton (@cityofhamilton) November 22, 2022

The city maintained that the drinking water of Hamilton residents was not affected by the leak, but the spill will have a great impact on the environment of the harbour. 

"In one word, the environmental impacts are unacceptable," the Director of Hamilton Water told reporters on Tuesday. 

The city revealed that 50 homes are tied to the pipe, and residents in the area can expect to see a high level of activity over the next few days as the city works to make repairs. 

Mayor Andrea Horwarth told reporters that she is concerned about the environmental impacts of this spill. 

"While we are not yet aware of the total volume of sewage released, I have been informed that it was substantial," Horwath said. "I was assured that the nature of the spill makes the risk to human health very low." 

The City of Hamilton also revealed to the public in 2018 about a 24 billion litre sewage leak that spilled into Chedoke Creek over a four year period. 

As a result of the most recent leak, Hamilton Water is reviewing its internal processes and identifying opportunities for future improvements to prevent similar incidents from occurring.