Moses Lake Watershed Council

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Frequently asked questions

What is toxic algae?

Toxic algae refers to a particular type of algae found in lakes and ponds called blue-green algae or cyanobacteria. This type of algae is a natural part of lakes, but sometimes it can grow rapidly or bloom. Lakes experiencing a bloom will look cloudy. The algae will begin to accumulate as a surface scum and often resembles blue or green paint. A handful of blue-green algae species sometimes produce toxins during blue green blooms.

Should I be concerned about toxic algae?

When blue-green algae is producing toxins - high levels can cause serious illness in humans and animals who play in or ingest affected waters. Toxic algae exposure can kill pets, waterfowl, and other animals. Pets who drink lake water are particularly at risk. Smaller children that may ingest water when swimming are also at higher risk.

What do I do if I see a blue-green algae bloom?

As soon as you see a bloom or possible signs of poisoning: 1. Avoid all contact with the water. 2. Keep pets and livestock away from the water. 3. Call the Grant County Health District at 509-766-7960 and report the location.

Can I eat fish from the lake when a toxic bloom is present?

One type of toxin, microcystin, can accumulate in fish tissues, especially in the organs (liver, kidneys, etc.). Concentrations in the tissues would depend on the bloom severity where the fish was caught. Take caution when considering consumption of fish caught in a water body where major algae blooms occur. Before eating, remove the internal organs, which may contain more of the algae/toxin.

How does the bloom impact wildlife?

Wildlife such as waterfowl and deer might also become affected by a bloom - particularily if they are consuming water with high concentrations of algal scum. Please report any incidents where you suspect wildlife may have been injured from these conditions.

What is causing the toxic algae blooms?

Blue-green algae is a normal part of the lake system and is always there in low numbers. Blue green algae blooms often occur in late summer and early fall. While temperature and sunlight play a role in blooms, often times excessive nutrients - particularly phosphorus, are the primary factors leading to blooms. Frequent toxic algae blooms are one symptom of excessive phosphorus pollution and a sign of declining water quality. Phosphorus pollution flows into the lake from the surrounding areas.

What can I do to help prevent toxic algae?

The best way to help prevent future toxic algae blooms is to reduce phosphorus coming into the lake. Even small reductions in phosphorus can make a big difference. Public meetings will be conducted throughout the year. The Watershed Council believes that participation by EVERYONE will help with the long-term solution of cleaning up the lake. To receive notifications about public meetings, email or call the Grant County Conservation District office at (509) 765-9618.

List of website Resources

Moses Lake Irrigation and Rehabilitation District - Grant County Health District - Washington State Department of Ecology - Washington State Department of Health Blue Green Algae Information - and Environment/Contaminants/BlueGreenAlgae Washingotn Stae Department of Ecology Freshwater Algae Control Program - Environmental Protection Agency (EPA) Nutrient Pollution - EPA Harmful Algae Blooms -

The Washington State Department of Ecology, Grant County Conservation District, Grant County Health District, Moses Lake Irrigation and Rehabilitation District, and the City of Moses Lake collaborated in developing the Moses Lake Watershed Council to explore alternatives for addressing water quality issues affecting the Moses Lake watershed. The Moses Lake Watershed Council seeks guidance from the public to explore long-term solutions to local water quality issues. 

Moses Lake and the surrounding watershed are susceptible to blue-green algae blooms. Blue-green algae is actually a bacterium called cyanobacteria that have similar qualities to forms of algae. Some blue-green algae produce toxins that are harmful to humans and animals. Blooms occur in the summer, when higher temperatures and elevated nutrient levels combine to create a thriving environment for blue-green algae. Whether or not blooms are toxic, they diminish the economic and recreational opportunities in Moses Lake and the surrounding region. 


If you would like to receive updated news about what the Council is working on, send an email requesting to be added to the Watershed email list to -  


The Watershed Council had a 1-day strategic thinking session with Washington State Conservation Commission facilitator, Ray Ledgerwood.  The group worked through their mission, short and long term accomplishments, structural framework, early actions, funding and grant applications.

The Council will be able to follow the plan to make sure the group is accomplishing the goals set out to seek long-term, sustainable actions to help with the water quality on Moses Lake.

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