Board the Sound Guard of Puget Sound-the research ship Sound Guard of King County sailed into the blue waters of Puget Sound for a water quality monitoring cruise.

The crew splashed water and threw the equipment out of the ship to test the chemical composition of the water. It was read 16 times per second to measure everything from the amount of light in the water to the level of dissolved oxygen in summer.

Although this monitoring is routine, the debate about how to best protect the health of Puget Sound is by no means the case.

The state's ecology department will decide whether to issue new general permits for all 58 sewage treatment plants around Sound as soon as the end of this month.

Ecology believes that as more people live here, they must not contribute more nitrogen from urine and worsen low dissolved oxygen levels. These levels are already present in certain areas of Puget Sound, especially in the summer.

"Puget Sound is developing very rapidly. We believe that we see a problem that needs to be resolved and the situation will get worse," said Vincent McGowan, head of the Department of Ecological Water Quality.

Over the years, the agency has been working to develop new permit requirements and develop computer models to inform the required nitrogen reduction levels. McGowan said it’s time to issue permits and involve sewer utilities and plan future nitrogen reductions.

Most sewage treatment plants need to clean and upgrade the nitrogen in the wastewater, so billions of dollars in taxpayer funds may be involved.

Sewage treatment plant management personnel strongly objected. They-and some scientists-believe that the dissolved oxygen problem in Puget Sound is serious enough to harm marine life in time and space, and most of it is naturally caused. So why do you want to do this? Public utility professionals say their credibility is at stake.

Dan Thompson, manager of Tacoma's sewage treatment department, said: "The real destructive thing is that if we build these things, we don't save the fish or the orcas." "I can never get from taxpayers anymore. I got a penny because I have lost all credibility."

McGowan and Ecology stepped up their rhetoric, warning in an institutional blog post in June 2021 that we are on the "fast lane to a dead zone."

Ecology spokesperson Colleen Keltz (Colleen Keltz) said that for the marine organisms affected by it, the small difference in dissolved oxygen does not seem to be small.

"Although the damaged area of ​​Puget Sound is only part of all ocean waters in the area, the damaged area is very important to protect healthy and robust aquatic species-we need to protect these species and the waters in which they live," Kyle Ci said.

"State of the Salish Sea" is a report on the health of the inland waters of the region. The author, published by Western Washington University in June 2021, including scientists from all over the region, pointed out that it is easy for people to see the complexity of the landscape, including mountains, valleys, plains, forests, and rivers. But they do not see the same complicated seascape as easily as Puget Sound.

Beneath its wide, gleaming surface are high thresholds that hinder the water cycle, deep canyons, coral reefs, shallow bays, seaweed forests, eelgrass meadows, which flood in and out of salt and fresh water every day.

Tides, ocean currents and circulations promote the exchange of energy, sediments and nutrients, thereby boosting the productivity of Puget Sound. By constantly moving water around the system, this physical flushing of incoming and outgoing water helps reduce human injuries, from pollution to low dissolved oxygen levels.

Lighter surface water flows to the Pacific Ocean on top of the denser seawater that flows inland. This two-way simultaneous vortex causes a complete exchange of Puget Sound water every three to six months.

Nitrogen is one of the nutrients essential for Puget Sound productivity-especially nitrogen from the Pacific Ocean, which is by far the largest single source of Puget Sound. These nutrients pour in from the ocean, bringing life-giving minerals and nutrients from the bottom of the food chain to the top predators.

However, there are too many good things.

Especially in summer, when the inflow of fresh water from the river is greatly reduced, the nitrogen content in some poorly washed areas of the Sand River will increase. In some ways, there is a delicate balance between adequate nutrition and excessive nutrition. When the algae die and decay, this may cause the algae to multiply, thereby depleting the oxygen in the water.

Marine organisms need oxygen dissolved in water, just like land and birds breathe air in the atmosphere. In addition to harming marine life, low oxygen levels can also damage the food web and even make the sea water more acidic.

Part of the dispute over the Ecology program involves a number used in its computer model that can generate damage predictions.

Since 1967, Washington has at least on paper limited the extent to which human influence may reduce the amount of dissolved oxygen in Puget Sound. This number is 0.2 mg per liter of water, but it has no biological basis. This is only the smallest reduction that can be measured at the time.

Using an impact of 0.2 mg per liter, the model predicts the difference in dissolved oxygen caused by the wastewater treatment plant, which is difficult to observe in the field; it is almost certainly not detected by salmon, shellfish or other marine organisms; University of Washington professor and Tacoma Joel Baker, director of the Puget Sound Institute, said they paled in comparison with the natural rise and fall of dissolved oxygen levels.

"I have worked in places with nutritional problems, such as the Great Lakes and Chesapeake Bay," Baker said. "This is not one of them."

Parker McCredy, a professor of oceanography at the University of Washington, found in his peer review of ecological models that hypoxia—the level of oxygen low enough to harm marine life—is a very limited problem in Puget Sound, and mainly It is caused by nature.

"If I were to describe the water quality of Puget Sound to the public, I would say that it is generally very good," MacCready wrote, adding that putting every bit of technology into the sewage treatment plant would not have much impact.

Gordon Holtgriff, an ecosystem ecologist at the University of Washington, believes that scientists have too many major unresolved differences on the way ecology is currently advancing general permits.

"It is reasonable to have real uncertainty and disagreement; this is not a deep weed of a group of scholars," Holtgriffe said.

He believes that taxpayers' money has better uses.

"It is incorrect to say that fish are suffocated by nutrients in the wastewater."

The controversial figures have been recorded for decades, and they are still the case-Nina Bell is far from losing that. She was the only employee of her non-profit organization Northwest Environmental Advocates, and she made regulators tremble in a post office box in Portland.

Bell said that under the Clean Water Act, she may be the most prolific person in the Pacific Northwest to file a lawsuit against the U.S. Environmental Protection Agency.

"I just want the "Clean Water Act" to take effect," Bell said.

She proposed a series of actions to try to force ecology to implement stricter supervision of sewage treatment plants. She attracted the attention of Governor Jay Insley.

He promised in a letter to Bell in March 2019 that Washington will soon limit the nutrients in the treatment plant. Ecology announced its decision to advance the draft license in January 2020, and launched public comment and virtual hearings.

Now, the agency is preparing to start a new era of community sewage treatment in Puget Sound.

King County (which also handles all of Seattle's sewage) asked the ecology department to suspend the issuance of new permits. Christie True, the head of the county government’s sewage treatment department, said that the county hopes to solve the scientific debate, and at the same time, when dissolved oxygen is known to be an issue, it can be achieved through various tailored strategies. Measured improvement.

Taxpayers have many interests. True said Ecology's plan would require King County to build a fourth treatment plant at a cost of between 9 billion and 14 billion U.S. dollars, which could more than double the sewer rate for King County customers (including Seattle).

Taxpayers in Seattle and King Counties bear the highest water and sewer rates in the country. Problems persisted, prompting the county to invest hundreds of millions of dollars in its largest sewage treatment plant, West Point in Magnolia.

Improving the reliability of the power supply and operation of the plant is the current focus. The catastrophic flood in the factory in 2017 destroyed expensive systems and equipment. Emergency overflows often dump untreated sewage into Puget Sound. The Suquamish tribe filed a notice in 2020, intending to sue the county for unprocessed discharge into Sound.

True said the county is committed to spending money to protect Puget Sound, especially as climate change and more people move here. But True says that using taxpayer money to make the right investment is crucial.

"We think the reason why the suspension is so important now is that it's just a huge promise of time, resources and money, and we really need to make sure we get it right."

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