Material from the dying blue-green algae bloom and other sediment is clogging the 12-inch intake pipe that brings water from the reservoir to Marion.

To fix the problem, the city will conduct high-pressure backflow this week that will flush the blockage from the pipe. The blockage should not affect customers, city administrator Roger Holter said.

The pipe is nearly 4 miles long and 12 inches wide, and if the city doesn’t address the issue then sediment will harden in the pipe and be more difficult to remove.

Flow to the water plant is down about two-thirds producing 400 gallons per minute instead of the normal 1,200. If the issue is not resolved, it could prevent the power plant from producing enough water for daily use; however, Holter said that is highly unlikely.

Unlike Marion, Hillsboro is not experiencing the same blockage problem because they use a pump to flow water from the reservoir to the water plant. The pump creates pressure within in the line that doesn’t allow sediment buildup.

In addition, this week the city will perform its annual burn-out which cleans sediment buildup from within city lines.

The burn-out will dissolve any sediment that may have built by adjusting chemical levels within safe consumption levels. Residents can expect their water to have the same taste and color, but with an increased bleach or chlorine smell, Holter said.