City trails in Edmonton's river valley are again open following Wednesday's storm.

Earlier in the day, the city assessed the damage to make sure the trails were safe for users.

Crispin Wood, manager of urban forestry, said the city anticipated fairly extensive damage throughout the trail system.

Signs were placed at most of the trail heads, Wood said.

A downed tree blocks passage on a trail in Hawrelak Park. (Trevor Wilson/CBC) About 800 reports came in from residents throughout the city about downed trees and branches, but the city expected more on Thursday, he said.

"Windstorms like this, particularly when the trees are in full leaf, are probably a once-in-a-decade event," Wood said.

The last destructive windstorm the city experienced was in 2009, he said.

"Given the high winds ... the trees with the full leaves on them act like a sail. These winds come in low to the ground and just grab the entire tree and snap it off at the base."

Priorities were given to trees deemed hazards or safety issues, Wood said.

Wednesday's storm packed winds of more than 70 km/h, according information from Environment Canada .

The city received about 800 reports from residents throughout the city about downed trees and branches Wednesday. (John Shypitka/CBC) Between noon Wednesday and 8 a.m. Thursday, about 22,000 customers were without power at some point.

Tim le Riche, a spokesperson for EPCOR, said power had been restored to the vast majority of them, but more than 100 small lines are still down in various locations throughout the city.

The Edmonton fire department worked with the power company throughout the day Wednesday responding to lines that had blown down in the wind or were tangled in nearby trees.

In a typical day, the fire department receives about 120 calls, said city spokesperson Maya Filopovic. On Wednesday, there were 343 calls. Fire crews also helped with roof collapses and with small structures that had been battered apart or blown away.

Filopovic also cautioned people to stay out of the river valley — and especially off low-lying trails — as the North Saskatchewan River is higher than normal because of the rain.