Heart Lake cleanup plan

One of the larger items on the July 10, 2017 City Council agenda was a proposed plan to clean up Heart Lake.  If successful the cleanup will lead to the lake being restored as a great place for family recreation: swimming, fishing, etc.

Just about everyone supports the having a great place for kids of all ages to swim.  But like many issues, this one isn’t a simple and automatic ‘yes’ vote.  Heart Lake has two main problems, both of which are relatively common to shallow lakes in the Pacific Northwest.

1.  Invasive Milfoil weeds growing up from the bottom.  These weeds were probably introduced years ago by a boat that had been in contact with Milfoil in another lake.  This is a common problem seen in lakes in Washington and Oregon.

2.  Algae; the gross green stuff floating on top of the lake.  Through the natural process of aging, the lake takes on more and more organic sediment, and it gets shallower.  As this process proceeds over many centuries, shallow lakes eventually transition to swamps or marshes, and finally into meadows.  Our best explanation for the algae in the lake is that its a symptom of this long transitioning process.  More info on algae blooms:  https://en.wikipedia.org/wiki/Algal_bloom

So, we have two problems, both of which can be treated.  However, both problems will require ongoing maintenance to not only clean up the lake, but to keep it clean.  

We’ll be treating the milfoil with an herbicide called fluoridone, which is known to be effective and has been used to treat a number of lakes throughout Skagit County and Washington State.  After the initial treatment in the fall of 2017 we expect to do small spot treatments on an ongoing annual basis.  For more information on fluoridone, including safety info:

http://dnr.wi.gov/lakes/plants/factsheets/FluridoneFactsheet.pdf

http://ccetompkins.org/environment/aquatic-invasives/hydrilla/management-options/herbicides/fluridone

We can treat the algae blooms with a compound called alum.  To quote from wikipedia:  Alum is used to clarify water by neutralizing the electrical double layer surrounding very fine suspended particles, allowing them to flocculate (stick together). After flocculation, the particles will be large enough to settle and can be removed.  For more info on alum:  

https://en.wikipedia.org/wiki/Alum

The initial treatments for both problems have an estimated total of $205,000.  To pay for it our Parks Department is allocating $155,000 from the ACFL quarry fund, and we’ll be receiving a $50,000 grant from the WA Department of Ecology.  

Ongoing maintenance:  The annual spot treatments for milfoil are estimated to be as low as $4000, and as high as $10000.  We don’t expect annual algae treatments, however, we should plan for another bloom within 5-10 years.  With this in mind, Parks staff have recommended we budget approximately $30,000 a year over the next 10 years to cover the annual milfoil treatments, and to set aside funds for a future algae treatment.

Summary - council passed a resolution on a 5-2 vote to proceed with the plan as outlined by our Parks Department team.  As I’ve noted above, there are a lot of variables in play and we don’t know exactly how the health of the lake will play out in coming years and decades.  We are moving forward with an initial treatment, and our resolution includes a plan for future funding.  However, it should be noted that if the lake doesn’t recover, or if the community’s priorities change in the future, the City will have the option reverse the decision to fund ongoing maintenance.  

Thank you Gary and John for your hard work, and for the research and time spent to come up with a solution which gives us the best chance of success.  And thank you for educating us on council on all the variables at play in this rather complex decision.