Toronto, Ontario (CBC News) - Ontario broke its record for single-day electricity consumption on Wednesday when it peaked at 26,160 megawatts, topping its previous high of 26,157 megawatts set on June 27.

Regulators say the system can handle the load and that there is still the option to import power from the U.S., and maintain a safety margin. But they are concerned that electricity usage tends to increase day-by-day as heat waves continue.

There was a localized blackout for half an hour in downtown Toronto when a Hydro One cooling pump failed, knocking out a good deal of power to Toronto Hydro. Officials also extended an extreme heat alert for the third straight day on Wednesday. Temperatures were expected to reach 35 C and feel like 41 with the humidity factored in.

It was the 17th heat alert of the summer for the city, which was also labouring under a smog advisory. The regional coroner’s office for Toronto East confirmed that a fourth person has died of causes directly related to this summer’s high temperatures.

The heat is creating other problems too: causing transformers to overheat, which in turn knocks out power to local neighbourhoods, usually for only 30-45 minutes at a time.

Power failures were reported in Midland, Brockville, as well as parts of Toronto overnight.

The heat wave is leading to other measures as well. The province is imposing a restricted fire zone across most of northeastern Ontario. All open burning, including campfires, is being banned from Marathon east to the Quebec border and from Manitoulin Island to Hearst.

The ban takes effect at midnight. In several Southern Ontario municipalities, authorities have instituted outdoor water use bans and farmers are worried about their crops.

“In order to have any significant recovery, we would need two to three inches of rain in the next week,” said soya bean farmer Lloyd Weber. “If we don’t get it, I would say we would be lucky to get a 50 per cent yield, in fact, less than that.”

The forecast is calling for rain sometime by the weekend, but probably not enough to solve the region’s agriculture problems. Environment Canada says the hot weather will continue until the end of July.

“In the next few weeks, we’re looking at a few nights when even the nighttime lows may only be in the 23 or 24 degree Celsius range,” said meteorologist Geoff Coulson