VANCOUVER - Heavy rain in southern British Columbia has eased but concerns about flooding remain high in dozens of communities from the Fraser Valley east to Alberta.

Environment Canada has lifted a special weather statement that forecast up to 40 millimetres of rain for the Boundary and Similkameen regions, which were already coping with thousands of evacuations caused by rivers swollen from snowmelt after recent hot weather.

Despite the improved conditions, flood warnings were posted Friday for the Salmon River near Falkland and Salmon Arm, as well as the Slocan River just north of Castlegar in the same area where more than 60 properties were placed on evacuation alert on Thursday.

Flood warnings remained in effect for the Granby, Kettle and West Kettle rivers affecting communities that included Grand Forks, which saw flooding last week as water reached historically high levels.

A spokeswoman for the Regional District of Kootenay Boundary says those rivers are expected to peak by midday Saturday.

Frances Maika said about 12 members of the military had arrived to assist with sandbagging and the Central Okanagan Regional District said 45 soldiers were working to protect a West Kelowna neighbourhood threatened by rising water levels from Okanagan Lake.

About 300 soldiers arrived in B.C. from Edmonton on Thursday in response to a provincial request for federal assistance as about 4,500 people have been forced from their homes by flooding and a further 7,000 have been told to be ready to leave on short notice.

The arrival of a contingent of at least a dozen members of the 3rd Canadian Division based in Edmonton has been a dramatic morale booster for overwhelmed residents of Grand Forks, said Maika.

“When you have children and elderly people sandbagging who are exhausted, to see 12 big guys show up who are fresh and have a lot of endurance, that's a good thing,” she said.

The community was preparing for the rivers to peak and Maika said that is expected before midday Saturday.

“We were looking (Thursday) night at two alternatives ... severe flooding or catastrophic flooding,” Maika said.

“It looks like, from the forecast right now, that severe flooding is our option.”

Once the waters peak, Maika said there's concern eroded river banks that have been supported by the raging waters could begin to collapse as the rivers recede.

About 40 riverside properties could be affected and Maika said owners have been warned to get out if they spot further erosion of the banks.

Officials were also keeping close watch on levels on the Fraser River from Prince George south to the Fraser Valley as evacuation alerts were posted in many communities along most of the river's length, although no severe flooding had been reported.

The River Forecast Centre says as much as 80 per cent of the annual snowpack still remains at higher elevations and high melt rates have gradually increased flows across rivers in the central and southern Interior. But the centre says the chance of those rivers flooding from snowmelt alone has fallen dramatically, although there was still a risk if heavy rains return.