Ty Swenson
While waterfowl still enjoy Hicklin Lake on a regular basis, it is rarely put to recreational use by humans. King County recently announced plans to try out a floating island that might help reduce algae blooms and bacteria in the water.

King County says they’ll pilot a floating island at Hicklin Lake in White Center

Friends of Hicklin Lake have been talking with King County politicians and scientists for months about having five floating islands installed at the heavily polluted body of water that, decades ago, used to be a favorite swimming hole for White Center locals.

It looks like their calls were finally heard, at least in part, since King County has announced plans to pilot a single island and monitor its success before committing further.

Floating islands are “Mother Nature’s way of cleaning polluted water by planting native vegetation on man-made islands,” Dick Thurnau of Friends of Hicklin Lake wrote recently. “Microbes attach to the vegetation roots (which) … devour the contaminants.”

Today, most do not go near the water. It has tested positive for a slew of contaminants over the years, including fecal coliform (aka human feces) since King County diverted drainage from the Salmon Creek Basin into the lake in 1965. The lake has no natural outlet, so those contaminants pile up. There is also plentiful algae growth that gives the water a green hue – not the most inviting for recreation.

On August 9, King County Department of Natural Resources and Parks (DNRP) director Christy True told Thurnau in an email, “We have done a great deal of research on floating islands and would like to pilot one island in Lake Hicklin. We may not be able to install it for budget reasons this year but will include in in next year’s budget. We want to get experience with one island and do some monitoring to see how it works.”

While one might assume King County’s plan to pilot an island is a victory for Thurnau and fellow Hicklin crusaders, they are concerned the plan is destined for failure.

The proposed pilot project
“One Floating Island will not compete well with the quantity of pollutants in Hicklin Lake,” Thurnau wrote in response to the county’s plan. “As an overly cautious experiment, a single island may lead you to draw incorrect conclusions.”

Sally Abella, a freshwater ecologist and senior engineer who researched the floating island concept for DNRP, said that while she understands Thurnau’s concern, there are funding restraints and scientific safeguards involved in the decision to go with one instead of five to begin.

Financially, Abella said the islands range (each) from $11,000 on the low end to $36,000 for a mechanized version that speeds along the filtration process, but the overall costs including installation and the need to get electricity to the islands (with the more expensive versions) would raise the price “considerably more.”

Abella said there were also a few questions about the scientific data provided to King County from Floating Islands International, the manufacturer they have been working with, including how effective they are in reducing phosphorous levels (which is Abella’s target, and key in reducing algae blooms). She said the company was also unable to provide clear reasoning for their estimate of five islands.

Based on those facts, Abella said King County wants to try one island and plans to set up numerous monitoring stations radiating from the island to the shore, so they can monitor phosphorous levels near the island and far away – a process she believes will produce clear data as to whether they should buy and install more. DNRP does not expect one island to cure Hicklin’s pollution woes, but wants to make sure floating islands are the correct path.

Abella said floating islands have been around since the early 90s, but do not have a track record with urban lakes in Washington State, so this would be new for the area.

As mentioned above, Abella hopes the islands will be successful in leaching phosphorous from the water, taking away a vital food source from the blue-green algae blooms she wants to avoid. Certain blooms can carry toxins that are dangerous to human and animal health, Abella said, although Hicklin is currently testing negative for that type.

An alum treatment done in 2005 was successful in killing off the algae blooms for about five years, she added, but another done in 2011 did not have the same effect. Floating islands might be a good alternative.

So what happens if North Highline gets annexed to Burien?
“The other factor is annexation,” Thurnau said of DNRP’s plan to, most likely, implement the pilot program in 2013. “I think they are just stalling until they find out what happens there.”

DNRP Deputy Director Bob Burns said Lakewood Park and Hicklin Lake will not automatically fall under Burien’s purview if annexation passes, but an affirmative vote would be followed shortly by meetings between Burien and King County. Burns said the county’s basic policy is to transfer ownership of local parks inside cities to that city. History, he said, leans towards Hicklin Lake becoming part of the Burien Parks Dept.

The big picture: To swim or not to swim?
Abella said her goal is to get Hicklin Lake as clean as possible, but there are limitations due to its size and location.

“It’s a different watershed now,” she said. “One of the reasons that this lake is the way it is is because of the way development proceeded (in the 1960s). There were not storm water controls when it happened and the engineering idea at that time was to get water off of the property as quickly as possible when it rained, so they directed storm water … into Hicklin Lake.

“That is a difficult thing to reverse … it appears that a lot of work that has been done in the watershed has reduced the amount of bacteria in the storm water and the lake has been pretty free of fecal choloform bacteria for some years now.

“From a bacterial point of view, it is probably safe to swim,” Abella added, “however, the county no longer has a beach or swimming program, they don’t have lifeguards on any lakes … so just from a policy standpoint they won’t be promoting swimming there anymore.”

She said history shows Hicklin had high bacterial counts back in the 1960s, when people were swimming there all the time.

“It is partially a public perception that the lake is a lot dirtier now. It is not necessarily completely true that it is dirtier than it used to be, but it is a small urban lake, so it’s not the same as a high mountain lake and it never will be.”

We encourage our readers to comment. No registration is required. We ask that you keep your comments free of profanity and keep them civil. They are moderated and objectionable comments will be removed.