The robot is clearing sediment from Prince Albert's River Street reservoir as part of the city's plan to get the water supply back to normal.

The robot is being used because the reservoir is part of the distribution system and can't be drained.

Two other reservoirs still need to be cleaned before the last step, which is flushing the lines that go to homes.

A boil water advisory was issued Feb. 3 because of problems at the water treatment plant and an emergency boil order followed on Feb. 7.

An official says the cleanup plan still needs to be approved by the province and it could be another three weeks before the boil order is lifted.

Copyright The Canadian Press