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.

A regional sewage-treatment system in Thurston County has helped contain  low-oxygen problems in Budd Inlet as the population continues to grow. The system cleans up some of the effluent for replenishing groundwater supplies.

High amounts of elements such as nitrogen can cause blooms of phytoplankton that sometimes trigger perturbations throughout the food web. This occurs most often in the spring and summer after the long, dark, cloudy days of winter begin to fade.

Under the federal Clean Water Act, states are required to assess the quality of their surface waters and compile a list of polluted water bodies. The law mandates cleanup plans to address pollution and other water-quality problems. This article describes how this process works in Washington state for dissolved oxygen. 

The Washington Marine Resources Advisory Council has released an addendum to the 2012 report Ocean Acidification: From Knowledge to Action. The original report established a statewide strategy for addressing ocean acidification in Washington. The addendum identifies updates based on emerging science and management practices and is intended to be a companion to the 2012 report. 

Sea lions living along the coast of Washington are at risk from harmful algal blooms throughout the year, according to a 2017 study published in the Marine Ecology Progress Series.

The Puget Sound Ecosystem Monitoring Program has released its sixth annual Marine Waters Overview. The report provides an assessment of marine conditions for the year 2016 and includes updates on water quality as well as status reports for select plankton, seabirds and fish.

The Salish Sea Model is used to predict spatial and temporal patterns in the Salish Sea related to factors such as phytoplankton, nutrients and Dissolved Oxygen. It is a collaborative effort between the Pacific Northwest National Lab, the Washington State Department of Ecology and U.S. Environmental Protection Agency.

The Puget Sound Ecosystem Monitoring Program (PSEMP) is an independent program established by state and federal statute to monitor environmental conditions in Puget Sound. 

Invasive species are considered a top threat to the balance of ecosystems worldwide. New discoveries of non-native green crabs in Puget Sound have highlighted that concern here at home, but invasive species can impact more than just the food web. Some introduced species can produce toxins that accumulate in shellfish or by directly infecting the human body.

The Puget Sound Ecosystem Monitoring Program released its fifth annual Marine Waters Overview this week. The report provides an assessment of marine conditions for the year 2015 and includes updates on water quality as well as status reports for select plankton, seabirds, fish and marine mammals.

Environmental samplers may provide early detection of harmful algal blooms (HABs) in Puget Sound. This toxic algae is expected to increase as the climate changes, bringing with it new and potentially more severe outbreaks of shellfish poisonings. 

It turns out that a gooey substance known as biofilm is a big deal for Salish Sea shorebirds, providing critical food for some species. But could a proposed port expansion in Vancouver threaten this slimy resource?

Researchers are studying how persistent pollutants such as PCBs avoid settling to the bottom of Puget Sound. This article continues our coverage of new theories on the spread of toxic chemicals in the food web. 

An algal bloom is a rapid increase or accumulation in the population of algae in a water system. While most are innocuous, there are a small number of algae species that produce harmful toxins to humans and animals.

Lake Washington was heavily contaminated by untreated sewage until extensive pollution controls by the city of Seattle. 

A report from NOAA and the Puget Sound Ecosystem Monitoring Program provides an overview of 2014 marine water quality and conditions in Puget Sound from comprehensive monitoring and observing programs.

A report from the Puget Sound Ecosystem Monitoring Program provides an overview of 2013 marine water quality and conditions in Puget Sound from comprehensive monitoring and observing programs.

The Puget Sound Marine Waters 2012 Overview from the Puget Sound Ecosystem Monitoring Program synthesizes conditions measured in 2012 and has been expanded to include observations on seabirds that rely on marine waters. Read an excerpt below, or download the full report.

The Washington Department of Ecology distributes a monthly report combining high resolution aerial photographs with satellite and ground-truthed monitoring data for Puget Sound surface conditions.

An independent review conducted by the Puget Sound Institute (PSI) is featured in findings by the Environmental Protection Agency and the Washington State Department of Ecology that there is currently “no compelling evidence” that humans are the cause for recent trends in declines in dissolved oxygen in Hood Canal.

The Puget Sound Marine Waters 2011 report is now available. The report was produced by the Puget Sound Ecosystem Monitoring Program and assesses the condition and quality of the waters of Puget Sound. 

Non-native species are those that do not naturally occur in an ecosystem. A non-native species is considered invasive when it is capable of aggressively establishing itself and causing environmental damage to an ecosystem. Plants, animals, and pathogens all can be invasive.