09/10/2014 10:51 EDT | Updated 11/10/2014 05:59 EST

Calgary Snow Knocks Out Power, Emergency Centres Open (PHOTOS)

CALGARY - Commuters needed hours to get to work, snow-laden tree branches groaned and snapped and thousands of people were without power Wednesday after a second major taste of winter hit Calgary with 10 days to go before summer's end.

Trees were uprooted and roads clogged with broken branches.

The power outages, which at one point affected up to 30,000 homes and businesses, also caused traffic lights to go out.

``We are going to see some real damage and that is an extraordinary shame,'' said Mayor Naheed Nenshi, who spoke at the city's emergency operations centre.

``I know how hard generations of people in this community have worked to build the tree canopy, but right now our focus is to make sure those fallen ones don't hurt people and don't cause further damage.''

Nenshi urged drivers to stagger their commutes home in an effort to reduce traffic congestion.

The amount of damage has not been assessed, he said, but he warned the cleanup wasn't going to happen overnight.

"We don't have a sense of it yet, but certainly, depending on the part of the city you're in ... I was shocked at the damage,'' he said.

"Out in the bald prairie, where I live in northeast Calgary, there was a little less damage. But this isn't something that will be cleaned up by the next garbage pickup.''

Story continues after the slideshow.

Photo gallery Calgary Snow, September 2014 See Gallery

The wet and weighty snowfall prompted the city to open its emergency operations centre for the first time since last year's heavy flooding.

Ken Uzeloc, director for the city's emergency management agency, said there was a serious backlog on the 911 call system, but it had been addressed by midday.

Considering the severity of the storm, things could have been much worse, he said.

"We have no indications at all of injuries and certainly no fatalities related to this event,'' said Uzeloc.

"I do want to commend Calgarians because usually in this type of a snow event early in the season we would have a large number of motor vehicle collisions and we have not.''

Pedestrians were bundled up in winter parkas and toques and tried to avoid being splashed by ankle-deep slush on streets.

Some were philosophical about summer's rude interruption.

"This is the Prairies. We moved back from Ontario and this is what we wanted,'' said Harold Clayton, who was walking downtown with his wife Susan.

"We want the Prairie weather and the seasons. So we'll get winter for a couple of days and then back to summer.''

The Calgary Board of Education said in a release that some schools were reporting power outages, but remained open.

The Calgary Zoo closed its doors for the day. It said heavy snow on trees near pathways posed a risk to visitors.

Officials at Spruce Meadows, who spent much of Tuesday removing snow from the show-jumping infield, announced Wednesday's opening event in the Masters competition was being rescheduled due to the ``extreme weather and hazardous conditions.''

Outside the city, farmers were also growing concerned about the snow's effect on the harvest. Producer Devin Harzler, who farms near Carstairs north of Calgary, said one of the big problems will be trying to salvage as much of the beaten-down crops as possible. He expects crop quality will take a significant hit.

"When we're out swathing we'll have to be scraping the ground to get everything off ... that we can,'' he said. "It's a little bit of uncharted territory for us. My dad was saying that the last time he remembers something like this happening in September was in 1968.''

The heavy snowfall warning ended Wednesday afternoon.

Sunshine was expected to return Thursday with temperatures returning to the mid-20s C by early next week.