A First Nations community in western Manitoba is facing flooding, just a year after cleaning up from a tornado.

About 145 people are out of their homes on the Sioux Valley Dakota Nation, located between Brandon and Virden north of the Trans-Canada Highway.

Of the 330 homes on the reserve, 45 are flooded, according to Chief Vincent Tacan.

Vincent Tacan

Chief Vincent Tacan said he has never seen the Oak River rise so high or so fast. (Caroline Barghout/CBC)

He said he has never seen the Oak River rise so high or so fast — even during spring flooding — as it did on Sunday, forcing people to scramble to get to drier ground.

The water is more than a half-metre above the deck of a bridge that crosses the river.

Several people with medical issues were sent out of the community to Brandon as a precaution, Tacan said.

The river, like many bodies of water in southern Manitoba and Saskatchewan, is swollen from heavy rain through the weekend.

As of Wednesday, about 500 people in Manitoba have left their homes because of the flooding, and 41 municipalities have declared a state of local emergency. Sioux Valley is among those.

In Saskatchewan, 54 communities have states of local emergency.

Much of that water in Saskatchewan is now flowing towards the already-flooded southwest corner of Manitoba.

Sioux Valley

The sign for Highway 21 into Sioux Valley Dakota Nation is suddenly in the middle of a prairie lake. (Sara Calnek/CBC)

Tacan is worried about just how much water is coming and is having trouble getting information from the province.

"I think they're having a little bit of trouble with their, whatever system they have in place to read the water levels and the volumes that are coming through," he said.

"I think they're still working some of the problems they have with that. It's not really an accurate system."

He said there was similar confusion during the flood of 2011, when the province came under criticism for its poor planning and flood forecasting.

A report from an independent task force put together in the wake of the 2011 flood, stated the Manitoba government should urge the federal government, which has primary responsibility for First Nations, to develop an emergency management plan for flooding on reserves.

Tornado injures 2

In July 2013, a tornado struck the Sioux Valley Dakota Nation, lifting one home off its foundation.

It damaged five other homes and sent one couple to hospital.

Environment Canada’s storm survey team said it was likely an EFO OR EF1 tornado — meaning the winds hit about 130 km/h.

Hundreds of trees were uprooted and the community was littered with debris.