Surface Water Management Division

Lake Howard Toxic Algae Bloom Alert

Last updated 11/16/2012

VERY LOW LEVEL OF TOXINS FOUND 11/13/12 

Throughout 2012, Lake Howard is being monitored by citizen volunteers and Snohomish County Surface Water Management for the presence of blue green algae blooms. This type of algae looks like green paint floating on the surface or small clumps floating in the  water, and can produce toxins. 

The most recent sample was collected on November 13, 2012 in response to new algae blooms on the lake.  Tests on this sample showed that there were very low levels of both liver and nerve toxin detected.  The levels were far below the Washington State Recreational guidelines for toxin exposure.  However, conditions can change rapidly - so please still do excercise caution particularly if you see algae scum.  Snohomish County SWM and volunteers will continue to check the lake for algae scums and test for toxins as needed.  Please do report any changing conditions (contact info below). 

CAUTION sign posted at Lake Howard - click to enlarge

"CAUTION"  signs that had been posted at the lake access points and will be re-posted if algae returns recommend: Do not swim in areas of scum.  Do Not Drink Lake Water Keep pets and livestock away from the lake Clean fish well and discard guts Avoid areas of scum when boating  If you or your pet are exposed to a blue-green algae bloom and have unexplained sickness or signs of poisoning, call your health care provider or veterinarian. For more information refer to our Toxic Algae page or visit the State Department of Health website.   For health related inquiries you may also call the Snohomish Health District at 425-339-5250. To sign up for toxic algae email alerts email Marisa Burghdoff.

Should I be concerned?

Yes. Toxic algae 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, especially dogs, are at particular risk. 

How should I respond?

• Follow the "CAUTION" sign advisory to not swim in areas of scum or ingest water, keep pets away from the lake, clean fish well and discard guts, and avoid areas of scum
  
• Contact your healthcare provider if you or your pets are ill after exposure*
  
• Return to this site to find out the latest testing results 
  
• Sign up to receive toxic algae email alerts by emailing Marisa Burghdoff

* For additional information on health risks or to report exposures contact the WA Department of Health at (360) 236-2251.

Is it safe to drink water from Lake Howard if it has been filtered?

The Snohomish Health District advises that lake water never be used as a drinking water source.  In addition, studies have shown that conventional water treatments such as coagulation, sedimentation, filtration, and chlorination are ineffective for removal of liver toxins associated with the toxic algae bloom at Lake Howard. For additional information contact the Snohomish Health District at 425-339-5250. 

How does the bloom impact wildlife?

Residents have noted that Lake Howard has wildlife that might be at risk from the bloom, including waterfowl and otters .  Unfortunately, wildlife are also susceptible to the toxins - particularly if they are consuming water with high concentraitons of algal scum.  Please report any incidents where you suspect wildlife may have been injured from the conditions. 

 

What is causing this problem at Lake Howard?

With the help of citizen volunteers, Snohomish County has been monitoring the water quality of Lake Howard for 19 years. Recently, the monitoring has shown trends toward poorer water quality in the lake.  Toxic algae blooms are one symptom of declining water quality. The water quality problems are mainly caused by high levels of nutrients, especially phosphorus, flowing into the lake from lawn fertilizers, failing septic systems, runoff from roofs and driveways, and pet and animal wastes.

Picture of 2011 algae bloom at Lake Howard

Where did the toxic algae come from?

The term "toxic algae" refers to a handful of blue-green algae species that sometimes produce toxins.  These algae are a normal part of the lake system and are always there in low numbers.  However, when high levels of phosphorus are present, the algae can sometimes grow rapidly - causing blooms.  As the algae die, the green scum forms on the lake surface.   

What can I do to help? 

Unfortunately, there is no simple lake treatment for toxic algae.  The best way to help Lake Howard and prevent future blooms is to reduce nutrients coming into the lake.  Snohomish County will be kicking off a new pilot program to help reduce pollution at Lake Howard this summer.  You can start acting today to protect your lake - find out more on our Healthy Lakes pages. Contact us (info below) if you would like to be involved or to find out more information.  

For more information

• Visit our Toxic Algae page
  
• Contact us (information below)
  
• Visit the State Department of Health website

• Visit the Lake Howard page

Test Date	Microcystin* ppb	Anatoxin a**  ppb	Above Recreational Standard
7/16/2012	104 ppb	Not Detected	YES
7/24/2012	1 ppb	Not Tested	NO
7/28/2012	>6 ppb	Not Tested	YES
8/8/2012	1 ppb	Not Tested	NO
8/16/2012	less than 1 ppb	Not Tested	NO
8/24/2012	>6 ppb	Not Tested	YES
8/28/2012	2700	Not Tested	YES
9/4/2012	0.26	Not Tested	NO
9/12/2012	<1 ppb	Not Tested	NO
9/18/2012	Between 1 and 6	Not Tested	NO
9/27/2012	<1 ppb	Not Tested	NO
11/13/2012	0.53	0.02	NO

*Microcystin is a liver toxin; the WA State recreational standard is 6 parts per billion (ppb)

**Anatoxin a is a neurotoxin; the WA State recreational standard is 1 part per billion (ppb)
 

Contact

Gene Williams, Senior Planner, 425-388-3464 extension 4563

Marisa Burghdoff, Water Quality Specialist, 425-388-3204

Jen Oden, Water Quality Specialist, 425-388-3464 extension 4352

 

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