Failed biofilter part of the problem, adding phosphorus, other nutrients that create toxic algae blooms
Clark County Councilor Gary Medvigy first learned about the regular water quality problems in Lacamas Lake a year ago. A neighbor approached him seeking water quality information from the county that apparently wasn’t publicly available. Over the ensuing year, Medvigy has gotten quite an education.
“What I did find out from county staff is these reports aren’t that available,” Medvigy said. “The testing wasn’t done. That’s when I first learned it’s an industrial lake. Staff didn’t treat it as a recreational lake. We didn’t test it as if people were swimming in it.”
That’s all changed now. The lake has been reclassified so that the county does more regular testing according to Medvigy.
A government website confirms Medvigy’s claim about no water testing. Going back to 2007, the majority of years show “no data” for four different toxins.
In 2020, Lacamas Lake seemingly had an explosion of algae blooms. For many residents, it seemed like there were constantly “caution” or “warning” signs around the lake. The water was unsafe and possibly dangerous to people and pets.
Between April and October 2020, Lacamas Lake was tested 29 times, 26 of which detected cyanotoxins, according to concerned citizen Marie Callerame. There were 14 weeks when toxin levels were “above state guidelines” for microcystin. The Anatoxin-A neurotoxin was found nine times and above the state guideline once. The county removed it’s most recent “warning” on Lacamas Lake Dec. 7 and their “caution” on Round and Hidden Leaf lakes Nov 24.
Presently, Medvigy is waiting for Camas to sign the interlocal agreement the county and the city negotiated, so that they can officially work together to solve the problem.
In Medvigy’s mind there are short-term issues and longer-term issues to be resolved. The short-term issues break down to adding oxygen to lake water, and then stopping the “pollution,” the untreated stormwater and nutrients from going into the lake.
“My goal is to not just spend money, analyzing the problem,” he said. “That’s more a mid-term and long-term goal to fix the whole watershed. If we could add oxygen right now, if we could spend some of the money available right now, we can start cleaning up the appearance and health of the lake.”
The addition of oxygen will reduce the impact of the phosphorus and nutrients that are in the water, which creates the toxic algae blooms. This will help improve overall water quality. It will also help fish and marine life come back and prosper. He’s heard stories and seen photos of dead fish in the lake water. “That’s got to change,” he said.
Medvigy knows there’s a debate about where all the nutrients are coming from. One group of homeowners along the south shore of Lacamas Lake have communicated with him, indicating their failed biofilter is a known source of phosphorus and nutrients. To Medvigy, getting the Lacamas Shores Homeowners Association to fix their failed biofilter is the low hanging fruit that should immediately be dealt with.
Medvigy has met with city and state leaders, including Councilor Steve Hogan and Sen. Ann Rivers, and many local concerned citizens. He’s brought county staff onboard the effort and wants to move quickly to begin the process of hopefully adding oxygen to the lake, and getting the homeowners to fix their failed biofilter.
Callerame introduced Medvigy to “nanobubbles.” She said it is a much more efficient, longer lasting method to get oxygen into the lake water to improve the overall health of the water.
Medvigy did a lot of research on his own. “I found a number of examples in the Northeast and in Florida.” He’s communicated extensively with one firm’s engineer about their nanobubble technology and has shared that information with Rivers and others. “This is a solution that Camas, Clark County, and the state should do right away.”
Medvigy learned that these nanobubbles are much more efficient for dealing with problems like algae blooms, and for cleaning up polluted water. Sewage treatment plants are using nanobubbles to help clean wastewater.
Nanobubbles are extremely small gas bubbles that have unique physical properties. These nanobubbles have a typical mean diameter down to 80 nm. Bubbles this size lack enough buoyancy to float to the surface. Instead they can remain suspended in water for months until they dissolve, traveling randomly throughout the body of water and efficiently aerating the entire water column.
Subsequently, dissolved oxygen (DO) measured at the deepest parts of a pond or lake will match the DO recorded near the surface. It is that increased oxygen which helps break down the phosphorus and other nutrients, and increases the water health for fish and marine life.
“The science indicates it’s aerating the water which does a lot of healthy things,” he said. “It accelerates the usage of the nutrients in the lake and eliminates them.”.
One firm indicates that roughly $1 million would put 10 nanobubble machines around Lacamas Lake. Given that Round Lake and Fallen Leaf Lake also have problems, they estimate about 20 nanobubblers would take care of all three lakes. Medvigy wants to get everyone on board, and then hopefully put out a competitive bid for a nanobubble system for the lake water.
One option might be to test it on a smaller lake like Round Lake or Hidden Leaf Lake first to confirm the positive effects of nanobubbles and measure the impact.
With regards to stopping the phosphorus and other nutrients from being added to the lake, Medvigy realizes that identifying all the possible sources of stormwater being dumped into the watershed will be a much larger, long term effort. “We’re going to bring everyone together, so no one can point the finger at someone else.”
Lacamas Lake used to be an industrial lake owned by Georgia Pacific for their mill in Camas. But a couple years ago, Georgia Pacific no longer needed the water for the mill, and gave the dam and its control of the lake water to the city of Camas. At that point it became a recreational lake, which should trigger higher levels of monitoring the water quality and the beach areas, according to Medvigy.
“You would have thought there was some criteria,” he said. “I don’t think there was any criteria — the language to change the testing frequency, to treat it as a beach, as a swimming area. It was a natural consequence of the city asking to designate it a recreational body of water. It should have happened years ago.”
That’s the crux of the problem according to Medvigy. “You have too many entities, the county, the city, the Department of Ecology, not necessarily sitting at the same table, talking about all the issues that need to happen.”
Medvigy hopes to bring the city, the county, the state department of ecology, and shoreline management groups together. They will hopefully create a plan they can all unite around, and get some county and state and possibly federal funding to study the entire watershed area. Medvigy thinks there may be an opportunity to get a college or university involved in a longer term study effort as well.
But he feels we need to address getting oxygen into the water now. We need to get the current developments along the south shore to address their biofilter issues now.
“It’s all of the development that’s happened north of Round Lake or on Prune Hill,” he said. “I don’t know the condition of all that stormwater drainage. Is it all being handled properly or are there more sources besides the biofilter that we know about, that are feeding into Fallen Leaf Lake, Lacamas Lake and Round Lake?”
The city of Camas allocated $300,000 in their biennial budget for Lacamas Lake water quality. How that money will be spent has yet to be determined.
Medvigy mentioned that the state Department of Ecology is just finishing up a major project with the east fork of the Lewis River. He believes the time is right to give them a new focus, and that it should be the Lacamas Lake watershed.
Medvigy also believes that what they learn in cleaning up Lacamas Lake will help them work to clean up Vancouver Lake, which has similar problems with toxic blooms.