Summit Lake remains closed to fishing and swimming, and residents have been asked to stop using the lake’s water in their homes until a toxic algae advisory has been lifted.
Thurston County Environmental Health officials are testing the water weekly. Two samples, taken from the lake on Monday, came back with levels of Anatoxin-A, a neurotoxin, that were “well over 100 micrograms per liter,” according to health officials.
The level to trigger a toxic algae advisory is 1 microgram per liter, according to environmental health specialist Jane Mountjoy-Venning.
Here are answers to some of the questions residents have asked health officials about the situation.
Q: How often does Thurston County test lakes for toxic algae?
A: County workers test for toxic algae as a response, Mountjoy-Venning said.
On May 4, the county received several calls from lake residents who reported an algae bloom. County officials took samples that day. The first round of samples included one that was confirmed at 354 micrograms per liter.
Q: When will the advisory be lifted?
A: To clear the advisory, Summit Lake will need two samples a week apart that are below the level that triggers an advisory.
“Last year, at Pattison Lake, there was an advisory on the lake for six weeks,” Mountjoy-Venning said. “So this may go on for quite a while.”
Q: What causes algae to become toxic?
A: “The algae is naturally occurring,” Mountjoy-Venning said. “ No one knows, despite research, what makes the algae then become toxic.”
Algae is dependent on sunlight, temperature, nutrients and the availability of resources, particularly phosphorus and nitrates.
Things that contribute to algae blooms can include fertilizer, animal waste and leaking septic systems.
“The reality is probably all of those combined (were factors at Summit Lake),” Mountjoy-Venning said.
Q: Tell us about the toxin.
A: Anatoxin-A is a nerve toxin.
“It’s been studied for several years because we’ve seen animals lick their fur and then suddenly die because they’re licking the scum off their fur and they also have the toxin,” said Thurston County Health Officer Dr. Rachel Wood.
According to Wood: The toxin affects what information gets passed on from one nerve to the next nerve. When that gets blocked, it causes paralysis and death. Sub-lethal levels may produce symptoms such as upset stomach, diarrhea and headache. Trembling, stumbling, tingling of the hands and feet also are symptoms.
Q: How can I avoid getting exposed to the toxic algae?
A: While the advisory is in place, Wood recommends residents avoid any contact with the lake’s water. Many residents pull their water from the lake, but now they should not drink the water or use it for dishwashing, showers or laundry, Wood said.
Q: What’s the risk of eating fish from the lake?
A: Although there is limited research on its effect in fish, it appears that the toxin could concentrate in places like the liver, Wood said.
“I wouldn’t eat the fish,” she said.
Once the advisory has been lifted, Mountjoy-Venning recommends people take extra care in cleaning lake fish if they want to eat them.
The state Department of Fish and Wildlife’s public access point on the lake is closed because of the advisory.
Q: How many people have been confirmed sick from the toxin? Have any pets gotten sick or died?
A: Wood said she has not heard of people sickened by the lake’s water.
Thurston County Public Health and Social Services director Schelli Slaughter said her staff has been in touch with local veterinarians, and they haven’t heard of any sick animals from the water, either.
Q: Can’t I go to the hardware store and buy a water filtration system that will remove the toxin?
A: There are products that will remove algae from water, but household filtration systems that can remove Anatoxin-A aren’t on the market, said Art Starry with Environmental Health.
Boiling or adding chlorine won’t treat it, either.
“If you boil it, it breaks up the algae and releases the toxin,” Starry said.
Q: Didn’t the county’s recent update for its septic system management plan include work to help protect Summit Lake’s water from contamination by leaky septic tanks?
A: There was a recommendation in the countywide plan to consider Summit Lake a special area with a focus for septic system maintenance, according to Starry.
The plan was adopted in November.
“It hasn’t been implemented,” Starry said. “At this juncture, we don’t have a funding mechanism to implement the plan.”
On April 11, the three-member Board of County Commissioners voted to toss out a $10 annual fee that 42,000 property owners with septic systems would have paid to help implement the county’s septic management plan. The two new commissioners campaigned against the controversial fee.
“We’re trying to figure out which elements of the plan will go forward or not,” Starry said.
Q: How did the samples from tap water taken from around the lake come out?
A: “The tap samples actually came out below the advisory level, so that was encouraging,” Mountjoy-Venning said.
However, she said only three tap samples were tested, and water moves.
“I understand that it may be very tempting to just think, ‘Well my tap is good, I’m just going to drink the water,’ but even a very, very little bit of this toxin can make you very sick,” Slaughter said. “So Dr. Wood’s recommendation is for anyone who draws their water from the lake when we know there’s a toxin above 1, that it’s not safe to use.”
Q: Can the toxin live on surfaces? If you wash dishes with it, and they dry, are you still in danger?
A: “I wouldn’t take the risk,” Wood said. “I’d rewash the dishes in clean water.”
Q: If you are exposed to the toxin, how long does it stay in your body? Is it permanent like mercury?
A: The effect tends to be felt within minutes or hours, and then it’s gone, Wood said. It doesn’t appear to accumulate in the human body, she said.
Q: Why can’t we wash our clothes in the water?
A: Wood said she’s concerned about any use of the water.
“You may inhale droplets, so we’re recommending you protect yourself from the toxin,” she said. “As best I know, I want you to be safe, so I’m erring on the side of being very cautious.”
Q: What can be done to remedy this situation? What have they done at other lakes with this algae?
A: “We wait it out,” Mountjoy-Venning said. “Research is ongoing. There doesn’t appear to be anything that one can do in the midst of an algae bloom, that one can add to the lake or do to the lake to make it go away.”
However, there are things that can prevent an algae bloom, such as cutting back on nutrients that get into the water. That includes making sure animal waste is picked up, septic systems are working properly, and fertilizer use is minimal, Mountjoy-Venning said.
Long Lake, Hicks Lake and Lawrence Lake have formed lake management districts that impose taxes to pay for projects on their lakes. Some lakes have done alum treatments, which helps cut down on the phosphorus in a lake, Mountjoy-Venning said.
Q: If you think you’ve been exposed to the toxin, what test can you ask your doctor to run?
A: There isn’t a test that can be done for Anatoxin-A, Wood said.
Q: Why didn’t the county test sooner?
A: At this point, the county’s algae testing is based on funding from the Department of Ecology and the Department of Health and is available specifically in response to algae blooms, Mountjoy-Venning said.
There are water tests that a property owner or a community association could pay for. More information about that is on the county’s website.
Q. The goose population on this lake has increased, and so has the goose poop. What can be done?
A: Homeowners can contact the Department of Fish and Wildlife to report the high number of geese on the lake, Mountjoy-Venning said.
In addition, homeowners can plant bushes between their lawn and the lake to discourage geese from walking ashore, she said.