Goodbye, 'pea soup': City funding cleanup of Kitsap Lake's persistent algae blooms

BREMERTON – It’s a familiar sight to residents living on the shores of Kitsap Lake: each summer, around the beginning of June, a bright green algae begins to creep across the water.

Cyanobacteria, or blue-green algae, is a potentially toxic algae that has been a persistent problem for homeowners and lake-users for years. Blooms can be harmful to people and pets and have forced closures of Kitsap Lake and its beaches every year for the last five years, much to the chagrin of residents like Jay O’Connor.

O’Connor, who has lived on the lake for 16 years, first noticed the blooms around 2008. The yearly explosions of algae seem to get worse every year, he said.

“We’ve done a lot of studies on the lake, we know what the problems are, they get grants, then they do the study, but nothing gets done,” O’Connor said.

That is changing this summer with the implementation of a city-funded plan to clean up Kitsap Lake.

Starting in June, contractors sprayed the lake with a compound called Phoslock, which helps remove phosphorous from the water. This week, an aquatic vegetation harvester trawled across the south end of the lake, chopping down underwater weeds and hauling them to shore.

The goal is to remove as much phosphorous from the lake as possible, city stormwater manager Chance Berthiaume said.

Sediment in the lake – from decomposing weeds, lawn fertilizer, stormwater runoff – produces excess phosphorous, which acts as fuel for algae blooms. Relatively few outflow points on the lake result in a slow turnover rate of water and poor nutrient cycling, according to a 2011 Kitsap Public Health District report.

The harvester removes plant life and opens the water up to circulation, allowing for the water to mix and more sunlight to reach the deepest parts of the lake.

“What it does with the E. coli, fecal coliform, is it neutralizes it or sterilizes it, just like UV disinfection at a drinking water plant,” Berthiaume said.

Berthiaume is taking the lead on the project for the city and will monitor the water quality as often as possible before making decisions about additional treatments or harvesting. At least one more Phoslock treatment and harvesting session is planned for this year.

Public health officials say it’s too soon to know if the treatment has made an impact. A cyanobacteria advisory was issued for Kitsap Lake on June 19 after a bloom appeared and remains in effect. An E. coli warning issued by the health district on July 30 was lifted Thursday.

While the bloom is still visible in the lake, toxicity reports analyzed this year have come back below the state standard, according to health district Water Pollution Identification and Correction Program Manager Grant Holdcroft. But he cautioned that conditions could change rapidly.

“A bloom that is not toxic one week can become toxic the next. There is no way of predicting when a bloom will start or stop producing toxins, or what level of toxins a bloom will produce,” Holdcroft said in an email to the Kitsap Sun.

Kitsap Lake has had 56 cyanobacteria “advisory days” through Aug. 5 this year, compared with 54 at the same time last year. In 2018, the lake had 89 advisory days by Aug. 5.

Residents who live on the lake say they have seen a marked improvement in water clarity since treatment began.

“Right now our lake is cleaner today than it was back in May when we had absolutely nothing,” O’Connor said. “It’s so clear right now, it’s crazy.”

Kevin Pentz and his family were frequent lake users growing up in the area, but it wasn’t until he bought a house on the lake about two and a half years ago that he realized how severe the algae issue was.

“My place, we would have it blow up there and the wind would blow our direction and it would be like pea soup,” Pentz said.

So far this year, Pentz has noticed only one similar “pea soup” level of algae near his home on the east side of Kitsap Lake.

“It’s just continually kind of getting cleaner and cleaner, which is the opposite, usually it would get worse and worse,” Pentz.

Berthiaume said there has been a desire to clean up the lake for years, but the project didn’t have political support until Mayor Greg Wheeler took office in 2018.

In December 2018, a group of lake residents reached out to the city to work on solutions. Wheeler made cleaning up Kitsap a priority of his campaign and pledged to use city money to kick off the process. The City Council agreed, approving $235,000 in a mid-year budget adjustment to fund Phoslock applications and harvesting this year.  

“I think it’s the city’s responsibility, not the entire cleanup, I just saw it was our responsibility to take the lead,” Wheeler said.

In addition to Phoslock and harvesting, the city will spray invasive weeds along the shoreline. Officials are also reaching out to residents to encourage them to take care of the vegetation on their property and avoid using fertilizer or other chemicals that could add phosphorous to the water.

Who will be responsible for the long-term maintenance of the lake is still up in the air. The city has a one-year contract with AquaTechnex LLC for 2020, but Wheeler has committed to pay for the work for three years.

Lake residents debated forming a lake management district and taxing themselves to pay for the treatment. Some residents, like Donald Gordon, have balked at the cost of additional taxes. Gordon moved to the lake with his parents in 1992 and recently purchased their old house. He said he appreciates the effort the city has put into the cleanup and would like to see the local government fund long-term maintenance.

“(A lake management district) doesn’t make sense to me, I understand people some people have the money and would like to make an immediate change, but for the average person to be able to afford living on the lake, you're going to tax the low man out,” Gordon said.

Wheeler maintains that the lake cleanup is a priority, and the city will work with residents on a plan to combat the algae blooms.

“We will reconvene and together we will work out a long-term maintenance strategy,” Wheeler said. “This is too important of an asset for the city to be out of it.”