Highway 5-A could be closed for weeks after Stump Lake spilled over its banks and flooded the highway about 40 kilometres south of Kamloops.
Kevin Skrepnek, the emergency co-ordinator with the Thompson Nicola Regional District, says water levels show the highway closure could last days or even weeks.
He says the reopening will be up to the Ministry of Transportation, which will factor in public safety.
Skrepnek says some outbuildings and basements on nearby properties have also been flooded.