On Monday, March 17, 2025, the Lakewood City Council is going to review studies of the water quality of Waughop Lake prepared by its contracted consultant firm TetraTech. The members of the City Council need to look skeptically at the assertions which will be offered by that firm.

In 2018, I began serving as the City's volunteer lake monitor on Waughop Lake, doing monthly sampling and data gathering. I had done the same tasks on Lake Louise since 2000, and took over in this role for Don Russell, who was having some physical difficulties doing the work. Don is still involved along with me in studying the health of Waughop Lake, or perhaps I should say the lake's lack of health.

Waughop Lake in Fort Steilacoom Park has long had problems with water quality, and especially with toxic algae. This is the legacy of the 80 years that the lake served as a dumping ground for farm waste produced by the farming operation run there by Western State Hospital. That farming operation ceased in 1965, but the residues of farm waste remain.

The farm once had a slaughterhouse built on brick pilings right over the lake, which made disposal of the offal much more convenient. There was a pigsty located right next to the lake, approximately where the south dock is located now, which made it convenient for the pig herders cleaning out the building to just dump the pig manure right into the lake. All of those nutrients are still in the lake, and for years helped to fuel excessive blooms of toxic algae.

Waughop Lake also suffered from approximately 40 years of episodic raw sewage discharges from nearby Pierce College, due to a plumbing design mistake made when the college was constructed. Sewage which was supposed to get pumped uphill to flow into the street sewer lines would sometimes get mixed in with the rainfall runoff and discharged into the lake. That meant more nutrients for aquatic plants and algae growth, but not in a good way. The college finally got that plumbing problem fixed in 2018, and interestingly the water quality started improving immediately afterward.

Pierce College runoff pipe with raw sewage, 2007 photo by Don Russell

The main nutrient of concern for toxic algae blooms is phosphorous. This element is needed for all life, plant and animal, and is in the fertilizer that you use in your garden. In lakes and rivers, though, excessive levels of phosphorous result in explosive "blooms" of algae, which take in the nutrients and multiply. Some species of algae excrete toxins as a defensive mechanism, chemicals which can damage the liver and nervous systems of mammals (like people and dogs).

Three separate studies have been done regarding what to do about this problem, starting with one by environmental consulting firm Entranco in 1978. That study recommended dredging the lake bottom sediments which harbor the high phosphorous levels. Another study was prepared for the City of Lakewood by citizen volunteers and academic experts, and at no cost to the City and its taxpayers. This study also recommended dredging the bottom sediments to a depth of 1 meter, since coring studies by the University of Puget Sound determined that the highest concentrations of phosphorous were in the top 1 meter (out of 6 meters of post ice age sediments).

The City of Lakewood ignored these two studies, and commissioned a third study costing $250,000 by consulting firm Brown and Caldwell, which was completed in 2016. It also recommended that the lake should be dredged to remove the phosphorous in the sediments.

The City Council did not proceed with these study recommendations, and instead followed the recommendation of its now-departed former public works engineering director, Paul Bucich. He hired the firm TetraTech to create plans to treat the lake with chemicals. What TetraTech formulated was a plan for a massive overdose treatment of aluminum sulfate, which happened with 2 applications in 2020 and a third one in 2023. TetraTech also supervised the application of those chemicals.

In a waterbody with pollution problems, especially from phosphorous, a treatment of aluminum sulfate works to bind up the phosphorous and make it "bio-unavailable" to the algae which need to use it to grow and multiply. When a treatment works right, the algae are reduced because they are starved of the key nutrient that they need. Green Lake in Seattle has had multiple aluminum sulfate treatments (because their effectiveness wears off). Wapato Lake in Tacoma has also been treated more than once, including one application in 2008 which was not conducted properly, and resulted in a big fish kill.

The aluminum sulfate molecule has two components, an aluminum ion and a sulfate attachment. The aluminum is what really does the work to bind to phosphorous, but it is not safe or practical to carry around and discharge unbound aluminum ions, so the sulfate attachment is used to make the chemical safer to carry and discharge.

When aluminum sulfate dissolves in water, it dissociates:

Al(SO) → 2Al³⁺ + 3SO₄²⁻Al₂(SO₄)₃ → 2Al³⁺ + 3SO₄²⁻

The aluminum ions (Al³⁺) then hydrolyze, reacting with water:

Al++3HO → Al(OH)+3H+Al³⁺ + 3H₂O → Al(OH)₃ + 3H⁺Al³⁺ + 3H₂O → Al(OH)₃ + 3H⁺

This forms aluminum hydroxide (Al(OH)₃), a gelatinous floc that's key to the process, while releasing hydrogen ions (H⁺), which lower the pH (acidify the water). The floc is what binds to the dissolved phosphorous. But the released hydrogen ions create a problem.

March 2020 aluminum sulfate discharge, photo by Tom McClellan

Using aluminum sulfate by itself makes the water incredibly acidic, which has obvious problems. So the applicators who discharge the aluminum sulfate into a lake also simultaneously discharge sodium aluminate as a "buffering" solution, meaning that it works to counteract the acidity created by the aluminum sulfate.

When sodium aluminate gets into the water, it too dissociates as follows:

NaAlO → Na⁺ + AlO₂⁻

In water, the aluminate ion (AlO₂⁻) reacts with H₂O and adjusts based on pH:

AlO-+2HO → Al(OH)+OH-AlO₂⁻ + 2H₂O → Al(OH)₃ + OH⁻AlO₂⁻ + 2H₂O → Al(OH)₃ + OH⁻

This produces more aluminum hydroxide and releases hydroxide ions (OH⁻), which counteract the acidity from alum by neutralizing the H⁺:

H++OH- → HO

All of that is great in terms of the water's pH, assuming that everything works right. But the complex stew of chemicals added to the water do not necessarily do only the things that humans want them to do. Here is what happens after treatment:

Solids: The aluminum hydroxide Al(OH)₃ floc, now laden with phosphorus, sinks to the sediment layer. Over time, it may form a cap that limits phosphorus release from the lake bed, though this depends on factors like oxygen levels (anoxic conditions can later release some phosphorus). And that layer can get disrupted in lakes that have a lot of bottom feeding fish, like the carp which for years have inhabited Waughop Lake. For that reason, aluminum sulfate is not recommended in lakes with bottom feeding fish, a point which the City of Lakewood and TetraTech ignored.

Dissolved Ions: The lake water will have elevated levels of Na⁺ and SO₄²⁻ from the dissociation of alum and sodium aluminate. These are generally harmless at typical treatment concentrations, though sulfate could contribute to minor salinity changes. It is worth noting that Waughop Lake's 3 aluminum sulfate treatments resulted in a total dose about 10 times the normal application concentration. This resulted in major salinity changes, as I discuss below.

pH: Thanks to the buffering, the pH should remain stable, avoiding drastic swings that could disrupt the ecosystem.

Phosphorus: Dissolved phosphate levels drop significantly, curbing algae growth. Total phosphorus isn't eliminated -- it's just relocated to the sediment as an insoluble form.

Rather than doing the industry norm which is a treatment at a dose of 5-10 mg/liter, consulting firm TetraTech recommended 3 total treatments at much higher doses. The first 2 were done in 2020 at a dosage of 40 mg/liter each, so 80 mg/liter that year. The third treatment was done in 2023, with an additional 20 mg/liter. This was a massive overdose at 10 times the industry standard. TetraTech asserted that this high dose was needed due to Waughop's high phosphorous levels.

The immediate effect after each aluminum sulfate discharge was that the water became exceedingly clear. During my monthly monitoring right afterward, I could clearly see the bottom of the lake 3 meters down, and the grayish cloud of the floc that covered the bottom. The aluminum particles had easily bound themselves to not just the phosphorous in the water, but to any other particles, pulling them all to the bottom. But pretty quickly that effect faded and the cloudy green algae returned. The algae problem which the treatment was designed to eliminate failed, and we now have new types of algae, some toxic, inhabiting the lake.

Part of my monitoring process is to use an item called a Secchi disk to measure how cloudy or "turbid" the water is. The disk is lowered until it cannot be seen any more, and that depth is recorded. On nearby Lake Louise, I can lower the Secchi disk 6 to 8 meters before it disappears. But in Waughop Lake, it only gets down 0.3 to 0.5 meters before it cannot be seen. The whole point of ridding Waughop Lake of algae has been a colossal failure, at least in terms of the effects on algae.

But that is not where the story ends. It gets even worse when we evaluate the adverse side effects of all of these chemicals being added. Above I described what the sodium, aluminum, hydroxide, and sulfur compounds all do in relation with each other.

One of the biggest effects is that the pH of the lake is now consistently much higher. pH is a measurement of how acidic or alkaline (basic) a chemical is. The pH scale goes from 0 to 14, and is neutral at 7.0. Below 7.0 means a solution is acidic, and above 7.0 means it is alkaline. Most lakes in western Washington are around 7.0 to 7.5, and that is where Waughop's pH was before the first treatments in 2020. But now Waughop Lake usually runs at 8.5 in the morning, and in the afternoons on a sunny day, the photosynthesis by the lake's algae can raise it up to 9.3.

For comparison, a properly chlorinated swimming pool should have a pH of 8.0. Every full point higher on the pH scale above 7.0 means that the solution is 10 times more alkaline. So the afternoon readings of 9.3 mean that the water in Waughop Lake is about 20 times more alkaline than a chlorinated swimming pool. You definitely don't want to get your skin (or your dog's) in contact with that water.

What this high pH does to the lake is that it affects the lake chemistry, especially all of the new chemicals that were added during the aluminum sulfate treatment. In high pH water, ammonium ions (NH+) convert to toxic ammonia (NH) which has adverse physiological impacts on all forms of freshwater aquatic life. The sulfide ions combine with hydrogen ions to form toxic hydrogen sulfide (HS) which to this day bubbles up from lake bottom sediments. The sulfide ions under high pH can also combine with the naturally occurring iron in the water to form insoluble iron sulfide, which denies that iron to plants and animals as a nutrient. So plants cannot make chlorophyll as easily, and animals cannot use that iron to make hemoglobin.

The sulfate and sodium ions combine to make a salt called sodium sulfide. This is different from the table salt (sodium chloride) that we put on our food and which is in the ocean, because sodium sulfide is so much more reactive, especially under high pH. Salinity is usually measured in water by evaluating the water's conductivity. Higher salt content makes the water a better conductor, which instruments can measure. Here is a chart of the conductivity of the water in Waughop Lake over time, measured in micro-Siemens per centimeter:

Data gathered and analyzed by Don Russell, chart by Tom McClellan

You can see the big rises which occurred with each of the 3 aluminum sulfate treatments. There is normal seasonal fluctuation as winter rains fill up the lake and dilutes it, then summer comes and it gets more concentrated again.

The high pH and high concentrations of chemical toxins have made it impossible for aquatic plants to grow in the middle of the lake. There are still some of the large lilies known as spatterdock along the south and west shorelines which existed before the treatments, but they are not looking as healthy as before. The once-prolific aquatic plants like coontail which used to feed the turtles, frogs, and visiting ducks are gone. The turtles which once inhabited the lake were non-native red-eared sliders, brought into Washington as part of the pet trade and released. So the treatments did not drive away any native turtle species, but their disappearance is still an indication of the toxicity and inhospitable lake habitat. These turtles will depart and travel over land to find a better water body.

The local Audubon chapter has done annual Christmas bird counts at Waughop Lake every year for several years. Here is a table of their findings.

Data compiled by Eric Chandler

The waterfowl which were prolific before the first treatment in 2020 are now mostly absent. Those which are seen in Waughop Lake are once which drop in thinking it will be a nice place to visit, but they do not stay.

Anglers used to come to Waughop Lake to fish for common carp and largemouth bass. They do not come around anymore, because they are not catching any fish. Carp were still seen spawning in May 2024, which is their normal spawning time, but the amount of spawning activity was diminished. That third aluminum sulfate treatment in 2023 seems to really have had a devastating effect on the remaining wildlife.

The first action which the City staff and City Council should enact is to sever all ties with TetraTech. That firm designed and supervised the application of toxic chemicals at overdose levels. That treatment failed horribly. So that firm and its consultants should therefore not be trusted for doing further studies of the environmental damage which ensued from these misguided actions.

The second action is that more communication is needed from the City to park visitors, telling people about the hazard that the lake water represents. Park visitors still let their dogs and children come into contact with the toxic and alkaline lake water. Written communications as well as signage at multiple points around the lake are needed to warn park visitors about the hazard. The old signs posted by Pierce County's Health Department have been removed, and they were woefully inadequate to describe the severity of the problem.

The third action is going to be the hardest. The State of Washington needs to be compelled to clean up both its original mess, and the toxic chemical mess we have now. The State of Washington did the original pollution of the lake through its farming operation. The State failed to supervise its own community college which discharged raw sewage into the lake for 40 years. The State was the permitting agency which authorized the overdose treatments with aluminum sulfate that were far beyond industry standards and sound environmental policy, and did so despite multiple citizen warnings about the hazards that would ensue. The principle in environmental cleanup is "Polluter Pays". It should not be up to the citizens of Lakewood to have to clean up the State's mess. And the City has proven itself not capable of sorting through the advice it has already gotten from consultants and getting to the right decision.

Solving the problem long term is going to be complicated and expensive, and all the more so now because of what the State allowed the City and TetraTech to do. The lake's sediments need to be dredged to a sediment depth of approximately 1 meter, which will involve hydraulic and mechanical dredging. That will mean removing about 150,000 cubic yards of wet solids. The dredging spoils will be mostly water, so that 150,000 will dry out to about 15,000 cubic yards, which is still a lot of stuff to get rid of.

Prior to the aluminum sulfate application, disposal of the sediments would have been much easier to accomplish than it will be now. Coring studies showed that the nutrient-rich lake sediments had roughly the same nutrients as TAGRO, the City of Tacoma's fertilizer product made from processed municipal sewage. I had identified a Tacoma fertilizer vendor before the treatments who was willing to purchase the dredging spoils for incorporation with his other fertilizer products, assuming that lab tests confirmed the nutrient loads.

Selling the dredging spoils is not possible now, because the presence of toxic chemicals in those same sediments resulting from the aluminum sulfate application means that nothing will grow in them. So those once valuable sediments are now worse than worthless. Now they are going to have to be hauled off and disposed of at a more expensive toxic waste dump as opposed to a regular landfill. And this is because the City leaders would not listen.

I hope they will listen now.

There are citizens in Lakewood who are available to work on a solution, and get the science and the action right this time. If our City leaders are smart, they will take advantage of these people, and form the right kind of advisory body to do the necessary staff work. The City Council should act now to establish such a body, and get started on a correct solution.