MOSES LAKE -— Samples of water from the system around North Elementary and along Patton Boulevard late last week met and were consistent with water quality standards. The discovery of discolored water Wednesday at North Elementary School prompted that campus’s closure through Monday. Discolored water also closed the Family Services of Grant County facility on Patton Boulevard. 

Chad Strevy, water department manager for Moses Lake, said city crews tested the water Thursday in the section along Patton Boulevard, known as the Larson pressure zone. It showed some discoloration, so crews flushed the lines. 

“We flushed all morning,” Strevy said. 

Water samples were tested for coliform bacteria; they came back negative for coliform bacteria growth. Sediment in water can provide favorable conditions for bacteria to grow. 

City officials monitored the water to ensure the sediment had been cleaned out, he said.  

“We’re going around spot-checking right now,” he said Friday morning. 

Moses Lake School District officials sent students from North Elementary to Larson Heights Elementary on Wednesday and closed North through Monday. Ryan Shannon, MLSD director of public relations, said the discolored water didn’t seem to affect Larson Heights. 

“We have initiated testing (at Larson Heights) as a precautionary measure even though we haven’t experienced any problems to date,” Shannon wrote in response to a Columbia Basin Herald email. 

Family Services of Grant County Director Sally Gundry said the facility has a policy that it’s closed when there’s a case of discolored water.  

The FSGC kitchen uses filtered water, Gundry said, and the classes use bottled water. But there’s a chance of contamination, so the facility is closed, she said. 

Strevy said sediment and rust from cast iron water lines collect during times of less water use, winter being an example. It’s stirred up when a large amount of water goes through the system. 

“It picks (the sediment) up, and the reddish color is usually the rust from the pipe,” he said. 

The source of the water can be a fire hydrant being flushed, but there can be lots of different causes. 

“It just takes a water truck filling up at a hydrant,” he said.  

As of Friday, city officials weren’t sure yet what happened on Patton Boulevard, Strevy said. The discoloration was consistent with sediment from cast iron water lines, he said, but city workers haven’t yet determined the source. 

Most of the water lines on Patton have been replaced over time, he said, but a section near Randolph Road still has cast iron lines.  

“We told people to flush their lines, and if you can wait a few hours, it will settle out,” he said.