How Harmful Algal Blooms puts dogs (and our health) at risk – and what to do about it

Excessive nutrients from toilets, soaps and food waste are leading to more toxic algae, insufficient oxygen and other problems. | August 5, 2021

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In the early 1500s, Swiss physician Paracelsus famously wrote, “Poison is in everything, and no thing is without poison. The dosage makes it either a poison or a remedy.” This medical maxim isn’t just something for old-timey doctors to live by (and ideally to not kill people by, but it was 500 years ago, so…). Our bodies are quite like nature’s systems; water and nutrients flow in and out, supported by — and supporting — other lifeforms in mind-boggling, elegant cycles. If one part of the cycle gets gummed up by too much of a good thing, the other parts react accordingly.

We’re talking, of course, about the most elegant, nutrient-rich part of our bodies’ and the planet’s cycles: Poop and pee — along with the other nutrient-rich stuff that goes down drains like soaps, fertilizer and food waste. Wastewater is full of nitrogen and phosphorus, two nutrients common in fertilizers that help plants and algae grow. But what happens when there are too many nutrients in a given system?

Less-treated wastewater = more toxic algae

Now, with a population-dense Western Washington and 67 wastewater treatment plants releasing water and excessive nutrients from toilets and sinks directly into the Salish Sea, we’ve got way, way too much of a “good thing”. Most of these treatment plants were built decades ago and were not designed to limit nutrient discharges or treat the range of contaminants wastewater now contains, including pharmaceuticals and even flame retardants.

The biggest issue — excessive nutrients — provide so much food for algae and bacteria that they grow explosively. When they die, they decompose and suck oxygen out of the water, leading to harmful algal blooms (HABs), dead zones where fish and other aquatic life cannot live.

To make matters worse, all the dead algae adds carbon dioxide to the water, which worsens ocean acidification and dissolves the shells of shellfish. As is often the case, climate impacts such as warming seas compound our challenges by accelerating algae and bacteria growth.

Oh, and certain types of algal blooms can kill pets.

Lax sewage treatment rules even puts dogs at risk

This summer, our pollution prevention specialist Kirsten was visiting one of her favorite state parks, Deception Pass, with her dog. Just as the dog was about to put her paw into the water, a woman on the trail yelled out a warning: “Hey watch out, my dog almost died from swimming in that same water just last week!” Many pet owners may not be so lucky.

Some species of algae produce toxins that, when ingested, are harmful or even fatal to pets and people alike. I’m very glad this other visitor and her dog knew to warn others, because it’s not always incredibly clear to the untrained eye when nutrient-laden water is host to these toxic algae. This is not a rare occurrence, either.

A higher standard for wastewater treatment plants

Even if Whatcom and Skagit Counties don’t have the metropolitan volumes of poop water chugging through its treatment plants that Seattle or Tacoma does, the accumulated contaminants add up. Combined, the two counties generate 57.67 million gallons of wastewater every single day — and that does not include places that discharge into rivers, such as Lynden in Whatcom County.

Prior to 2021:

  • Existing standards only required plants to use “Secondary” treatment, which does not control nitrogen, the main pollutant in our wastewater.
  • Washington Tribes identified the need to upgrade wastewater treatment plants as integral to supporting treaty rights. Anything that impacts aquatic life, such as shellfish or salmon, impacts people.
  • Needed upgrades would only get more costly over time, and more urgent as growth continues and climate impacts exacerbate our problems. Delaying this transition would have only increased the financial burden on future generations.
  • Seattle and other large producers of wastewater were lagging behind smaller towns like Sequim, which has a state-of-the-art treatment plant. Since the Puget Sound’s waters are very interconnected, pollution travels far from large sources.
  • 16 plants had already upgraded their nutrient-removal technology in the Puget Sound region, as well as Spokane and other eastern Washington communities. 

That’s why in 2021 we joined with partners across the Puget Sound region to call for a stronger permits for wastewater treatment plants. Nearly 300 of our supporters spoke up and the Washington Department of Ecology strengthened pollution standards for wastewater treatment facilities that empty into the Salish Sea. 

More than wastewater

Wastewater treatment plants are a major source of excess nutrient pollution in our region’s waters, but they aren’t the only ones. Land disturbances from development and logging, phosphorus-based lawn fertilizers and yard waste, pet waste, and agricultural activity can all contribute to excessive build-ups of nutrients in local creeks, rivers, lakes and seas.

What to help reduce excess nutrient pollution that can cause harmful algal blooms that shut down local beaches and shellfish beds and put people and pets at risk? Sign up for our E-News and Action Alerts so you never miss an opportunity to speak up for stronger water protections. 

Think you’ve encountered a harmful algal bloom nearby? Call our water pollution hotline: (360) 220-0556.

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