“For another two days, folks, can we try and avoid as much travel as we possibly can?” he said Tuesday afternoon. “If it is at all possible for employees to work from home, let them work from home.”
Crews were expected to restore electricity to most downtown buildings overnight Tuesday.
Nenshi asked that anyone planning to travel in the area try to carpool, bike ride or take transit.
The city is opening temporary "park and bike" spots to help ease traffic into the downtown.
About 13,000 homes and buildings were still without power Tuesday night, including homes in Inglewood, Riverdale and Bowness.
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Calgary's Beltline, a neighbourhood adjacent to downtown, is expected to have power by Thursday. Electrical workers are pumping out water in the Beltline to deal with underground substations and transformers, but it is slow going because the water keeps filling back up, said Enmax CEO Gianna Manes.
About 130 underground vaults are still affected by floodwater, said Manes.
Enmax made the decision to restore power following inspections by city officials to make sure the buildings were safe. A small number of businesses in the area may still be without power because of specific electrical or structural issues that need to be resolved, city officials say.
“I want to have people going back in and having a sense of normalcy as quickly as possible,” said Bruce Burrell, Calgary Emergency Management Agency director.
“These people [city workers] are working all the time, not only looking at what we need to do today, but what does this need to look like three or four days from now.
"And, folks, this is a big disaster, we’re going to be working on this for a few more weeks," Burrell said.
C-Train service across the city and parts of the downtown core has also been expanded, including on some lines that are now fully operational. For the most up-to-date information on service, visit Calgarytransit.com.
A number of bridges have also been reopened, either partially or in full.
Few venture downtown Tuesday
City officials had asked all downtown employees to stay home Tuesday, even though parts of the downtown core had been reopened. Street traffic was a mess following a partial reopening of the core over the weekend, and they asked that the core be open to residents only.
"We have a lot of work to do downtown, and it's best to stay out of the way of people doing that work," Nenshi said.
He urged Calgarians to continue helping out neighbours as the city recovers from last week's floods. "There is nothing preventing you from knocking on your neighbour's door."
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Nenshi also cautioned against people using generators indoors.
Over the past few days, TransAlta has managed to reduce the flow rate in the Bow River significantly. With water receding, the city is taking steps to begin restoring some normalcy for Calgary residents.
Three senior facilities in Bowness have reopened and MacLeod Trail will open to local traffic Wednesday morning.
There is no boil-water advisory in Calgary, but residents are being asked to conserve water. Officials are cautioning people that disinfectants in the city's water might make it taste funny, but the water is still safe to drink.
Mayor Nenshi warned people to stay away from High River, the southern Alberta town that fared worst in the floods.
"Don't go there and gawk and take pictures," said Nenshi. "It's an unbelievable emergency that they haven't seen in generations."
Alberta Premier Alison Redford has warned the cleanup effort could take up to 10 years.
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