Algae Problem In Newman Lake Due To Broken Submersible Pump

Algae in Newman Lake was worse than usual this summer.

The pesky underwater slime had a chance to bloom after the pump that carries oxygen to the deepest parts of the lake broke down in June.

It took almost the rest of the summer to haul the underwater pump out of lake, have it repaired and then return it to the lake bottom, said Marrianne Barrentine, a Spokane County engineer assigned to Newman Lake.

“It happened at the worst possible time,” she said.

Like other small lakes, Newman Lake becomes stratified during the hot summer months. That means water warmed by the long, sunny days doesn’t mix with the cooler water near the lake bottom, Barrentine said.

Because the deepest water is not exposed to the air, it is never replenished with oxygen. Underwater plants can quickly use up the oxygen which destroys fish habitat and makes the water more likely to have ugly algae blooms.

The underwater pump in Newman Lake pipes oxygen into the lake’s deepest water and helps circulate the water.

Barrentine said the underwater pump broke down in June after a bolt mounting the propeller came loose. Crews put it back in the lake on August 23 after the propeller was repaired and some other routine maintenance was completed.

“It was really due for an overhaul anyhow,” Barrentine said. The last time it was tuned up was about 7 years ago.

The Newman Lake Flood Control District had to dip into its reserve funds to pay for the repair, Barrentine said. It cost about $21,000, including the high cost of hiring a boat and divers to remove and replace the pump.

It has been working fine since it was restarted late last month, Barrentine said. The lake also has an alum injection system to help control the levels of pollution such as phosphorous.

Barrentine said the district also spent about $10,000 to scrape the silt from the sump at the lake’s outlet. She said heavy spring runoff clogged it with sediments which could have led to overflow and flooding in the spring.

The district works with the Newman Lake Property Owners Association and the Newman Lake Watershed Committee to monitor the water quality in the lake, work on watershed restoration projects and track any shoreline violations that could endanger the lake.

This sidebar appeared with story: LEARN MORE Take a tour

You can learn more about protecting Newman Lake from pollution at a tour of the watershed next weekend.

Volunteers with the Newman Lake Watershed Committee will hold a tour of the lake including the surrounding forest, streams, flood plain, and its treatment system on Sept. 30.

“We’re trying to reach out to the community to educate them about the watershed and its relationship to the lake,” said Margo Wolf, head of the Newman Lake Watershed Committee. “We want to show how each of the systems within the large ecosystem work together.”

A soil scientist, two foresters and other officials will lead the tour to show how the areas within the watershed can affect lake water quality. It will begin at 9 a.m.

All ages are welcome on the tour but there is limited space. Those who want to attend should call ahead so organizers know how many people to expect. For more information, or to register, call Wolf at 226-2079 or Spokane County engineer Marrianne Barrentine at 477-7443.