Over 100 residents of the James Smith First Nation have been forced to leave their homes because roads into the community, ravaged by high water, have made the place inaccessible to emergency vehicles.
The evacuation, which began Thursday, has families staying in hotels in nearby Melfort.
Major roads in the community are under water that is almost two metres deep in spots.
Rey Lindain, health director for the First Nation, said the concern for emergency access is real.
"There was an incident over the weekend where an ambulance had to turn around," Lindain said. "It took them two and a half hours to transport the client."
In addition to hindering traffic, the flooding has affected the reserve's water system and many basements are full of water.
The Red Cross has been helping to coordinate the evacuation.
"Their homes ... are being threatened so there's some stress around that," Deanna Down, from the Red Cross, told CBC News. "We provide the registration and we have them housed and their basic needs are being met."
Bill Marion, from the community's public works service, said a cumbersome third-party management system has made it difficult for the reserve to tend to road repairs or even purchase pumps to deal with the excess water.
"Now that we've had this seven day stretch of nice weather, we should have already been out there pumping the water out," he said. "We should already have been putting culverts in and repairing roads, it's setting us back."
Marion said if dry weather holds for a few days, crews may be able to have roads repaired by Tuesday.
The James Smith First Nation is about 160 kilometres northeast of Saskatoon.