A senior City of Winnipeg lawyer has been fired after a lawsuit over a water treatment plant went down the drain.

In December 2015 the city launched a legal action against several companies over the construction of the Deacon reservoir water facility.

The suit alleged a number of problems with the plant including a leaking roof.

But Mayor Brian Bowman confirms the lawsuit has been terminated over a human error. The city messed up a timeline during the legal process.

Bowman says as a result the lawyer responsible has been let go.

"It's Inexcusable that this kind of mistake would be made," said Bowman.

Bowman calls the mistake a big deal as the city was trying to recoup up to $20 million dollars for the repairs.