Ballooning cost overruns for the construction of Winnipeg's new police headquarters was the final straw that led to the end of Phil Sheegl's role as the city's chief administrative officer.

Sources tell CBC News the overruns to transform the former Canada Post building on Graham Avenue into the police HQ are now in the range of an additional $10 to $17 million above previously reported overruns of $28 million.

Police HQ

Sources tell CBC News the overruns at the police headquarters are in the range of $10 million to $17 million. (Brett Purdy/CBC)

Councillors on the mayor's executive policy committee learned of the growing costs in late September. Sheegl was directly involved and was already on the hot seat for the fire hall land swap.

EPC members were not able to determine who authorized the change orders that contributed to the extra costs for the police HQ and Sheegl couldn't tell them who did.

At one point the majority of EPC members wanted to wait until the fire hall audit was public before getting rid of Sheegl, but the cost overruns at the police HQ pushed them to act.

Five of the six councillors on EPC sent a letter to Mayor Sam Katz calling for Sheegl's resignation. The sixth member of EPC, Jeff Browaty, was out of town. The decision to write the letter was led by Transcona Coun. Russ Wyatt.

Sheegl's lawyers demanded he be allowed to leave his job before the fire hall audit was released and be given 18 months' severance pay.

Sheegl left with 12 months' compensation as dictated by his contract.