The DPW will shut off water service on Standard Oil Hill and the East Point Loop from the airport to the APL dock for four hours on Friday morning. (KUCB Stock)

The Department of Public Works will be flushing water lines on Standard Oil Hill Friday morning. That means residents will be without water for about four hours.

Water service will be shut off in the Standard Oil area and on the fuel dock side of the East Point Loop from 8 a.m. until 12 noon Friday.

"The reason for that is to redirect the flow so that the flow goes through the lines we're actually trying to flush," says water utility manager Clint Huling. "It'll also eliminate unnecessary mud and debris from traveling down all those different lines, and it'll shorten the length of time that the dirty water is passing by each location."

He says people on Biorka Drive and Delta Way will have low water pressure during the four hours. They should try not to use their water, to avoid drawing in sediment. After noon, he says residents can run cold water through a tap without a filter for a few minutes to clear out any debris.

"Especially if they flip on their faucet for hot water, they're going to suck that dirt into their water tank," he says. "And then the only way to get it out is to flush the water tank itself."

This is the second routine flushing on Amaknak island in the past few weeks. But Huling says it’s taken a long time to get to this point. Unalaska's water lines are sized for a town 10 times as big, in order to meet processing demand. Huling says the city’s had to build extra blow-out points to help clean the pipes over the past few years.

He says they’ll flush the lines on Ballyhoo Road and in Unalaska Valley after the processing A season ends.

Residents can call the DPW at 581-1260 with any questions during Friday's outage.