Cooling system of one of Canada's most important carrier hotels, 151 Front St. in Toronto, went down as a result of a power outage caused by flash flooding Monday evening. The building houses several data centers, neither of which have reported outages, as the building was switched to generator power.

Representatives from one of the data center providers, Peer 1, posted an update on a customer forum, saying the power issues did have an effect on the building's cooling capacity.

“The building's chill loop provider also experienced power issues which impacted the cooling capacity of our AC units,” the post read. “Due to this, our data center experienced higher-than-normal temperature levels.”

According to news reports, utility power outages affected about 300,000 homes and businesses in the city. In a notice posted on early Tuesday afternoon (local time), Toronto Hydro (the utility serving the city) said about 50,000 customers remained without power.

The utility turned off service to about 30,000 of those 50,000 customers to reduce stress on the grid.

Most of the city's electricity problems stemmed from one off-line station. The Hydro One transformer station was under more than 20 feet of water, Anthony Haines, CEO of Toronto Hydro, told reporters in a press conference Tuesday.

The transformer station's outage put stress on the entire system, Haines said, pleading with city residents to reduce their electricity use until the system is restored to its normal capacity, CTV News reported. The city needed to cut power consumption by about 200MW during the afternoon peak-usage period, he said.

“The system is operating beyond its operating capacity as I stand here in front of you right now,” CTV quoted Haines as saying.

Utility power to 151 Front St. was restored at least by about 5pm Monday, according to the update on the Peer 1 forum. “The building is currently back on commercial power and the chill loop provider is also restoring to normal operational levels,” the post read.

About one hour later, the forum was updated to note that temperatures on the data center floor had been restored to acceptable levels.

Other data center operators in the building include Equinix and Cologix. Representatives from neither company could provide comment in time for publication.

Tenants affected by the power and cooling issues in the building included hosting companies Priority Colo and Korax and voice and Internet service provider Voice Networks, according to their respective Twitter feeds.

Voice had network issues during the air-conditioning outage, and Korax had “a few servers down” on Monday evening.