Nutrient pollution

Nutrient pollution is caused by excess nitrogen and phosphorus in the air and water. Nitrogen and phosphorus are nutrients that are natural parts of aquatic ecosystems. Nitrogen is also the most abundant element in the air we breathe. Nitrogen and phosphorus support the growth of algae and aquatic plants, which provide food and habitat for fish, shellfish and smaller organisms that live in water. But when too much nitrogen and phosphorus enter the environment - usually from a wide range of human activities - the air and water can become polluted. Nutrient pollution has impacted many streams, rivers, lakes, bays and coastal waters for the past several decades, resulting in serious environmental and human health issues, and impacting the economy.

-- Source: U.S. Environmental Protection Agency

A milky, turquoise, phytoplankton bloom in Hood Canal visible from space. Natural color MODIS image from Landsat 8 acquired July 24, 2016. Photo: NASA Earth Observatory https://earthobservatory.nasa.gov/NaturalHazards/view.php?id=88454

OVERVIEW

Does Puget Sound need a diet? Concerns grow over nutrients

As the region's population grows, scientists say we can expect to see increasing amounts of nitrogen and other elements flowing into Puget Sound. Known as “nutrients” these elements are naturally occurring and even necessary for life, but officials worry that nutrients from wastewater and other human sources are tipping the balance. That could mean big problems for fish and other marine life, gradually depleting the water of oxygen and altering the food web.

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Image of tidal motion in SSM (72 hr animation, April 06); Exaggerated vertical scale to visualize SSM domain-wide tidal motion
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The Salish Sea Model

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