EDMONTON -- An ice jam on the Athabasca River is nearly half the size it was earlier this week when it caused major flooding in Fort McMurray and forced 13,000 people from their homes.

The Regional Municipality of Wood Buffalo says the blockage was 13 kilometres in size Wednesday night, down from 25 kilometres two days before.

And, the level of the Athabasca River dropped 3.5 metres overnight, and the Clearwater River by about one metre.

The news is all good — but doesn’t mean Fort McMurray is in the clear.

“Although water levels may be dropping, the river hasn’t broken,” Scott Davis, Wood Buffalo’s director of emergency management, said.

“River break up has not been declared. These areas still pose a risk due to fluctuating water levels, scattered debris, and damaged infrastructure.”

The continued risk is posed by an ice jam between five and eight kilometres in size on the Clearwater River, upstream from downtown Fort McMurray.

“Should that break up and flow through in a natural manner, then the risk is low. However, we have to be cognizant that if the ice jammed again in the same location as the lower townsite, we could have another problem of flooding,” Davis explained.

He said officials were keeping their fingers crossed that Mother Nature will continue to act favourably.

The developments have prompted questions of reentry from residents and business owners in Fort McMurray’s lower townsite. Mayor Don Scott reiterated there was much to do before people could return home: safety assessments, restoration of gas and electric services, ensure businesses providing food and supplies were operating to support returning residents.

Environment and Parks Minister Jason Nixon said the province would be helping the municipality with the reentry phase when it was ready.

"It's important to remember that we still have floodwater in these communities and our first priority is to protect communities.”

Mandatory evacuation orders remain in place for Draper, Waterways, Taiga Nova Eco-Industrial Park and Fort McMurray’s lower townsite.

With Red Cross fully set up in the municipality, everyone impacted by the flood was urged to register with the agency. Evacuees should call 1-800-863-6582 between 8:00 a.m. to 8:00 p.m., including those who had already registered with the municipal evacuation centres.

The Regional Municipality of Wood Buffalo is scheduled to host a virtual townhall at 5:50 p.m. on Thursday.

At-home instruction for public, Catholic and Francophone students was also cancelled for the remainder of the week, due to two schools being impacted by flooding.

FLOODING DANGER HAS ‘PASSED’ IN FORT PEACE RIVER REGION

Meanwhile, a second northern Alberta community declared the local flooding threat over on Thursday.

The level of the Peace River dropped 2.5 metres and the ice mass shrunk to 24 kilometres in length overnight, allowing the jam to move downstream of Garden River.

This caused flooding at the Little Red River Cree Nation and 749 people needed to be evacuated from the area.

Additionally, about 455 people remain evacuated from Fort Vermillion.

However, without heavy precipitation forecasted in the area and the river continuing to flow downstream, local officials said they could begin planning reentry into the communities.

“It’s a great pleasure to announce the flooding danger has passed,” Mackenzie County Reeve Josh Knelsen said.

While water levels along the Peace River are expected to remain high, experts say it is unlikely they will spill over the bank again. As such, damage assessments have begun and crews have started cleanup, including removal of ice from the road.

There is not yet a timeline for residents to return home, but Knelsen said it would be a phased reentry.

Evacuees had the chance to join a bus tour of the community Thursday afternoon. 

Evacuated Mackenzie County residents, same as those in Fort McMurray, are eligible for emergency cash payments of $1,250 per adult, the province announced Wednesday.

To date, the flooding in northern Alberta has claimed one life, that of a 59-year-old Fort McKay band member who was with his son-in-law on Tuesday when the ATV trail they were on suddenly flooded. 

With files from The Canadian Press