We monitored three beaches in Island County from June 1 through Aug. 31, 2020:
- Dave Mackie Memorial County Park
- Freeland County Park, Holmes Harbor
- Windjammer Lagoon
Freeland County Park in Holmes Harbor has a swim advisory from June through mid-Sept. due to bacteria levels.
Keeping beaches safe
The Beach Environmental Assessment, Communication & Health (BEACH) Program ensures that marine water is safe to swim and play in and informs the public if water doesn't meet swimming standards.
From Memorial Day through Labor Day in 2020, we sampled 63 public high-use beaches statewide, either weekly or biweekly, for enterococcus, a type of fecal bacteria. High enterococcus levels are linked to swimmer illness.
Island County saltwater swimming beaches
We monitored three beaches in Island County weekly from June 1 – Aug 31, 2020.
Find details about each of the Island County beaches below:
During the 2020 monitoring period, Dave Mackie Memorial County Park had very good water quality. This beach was sampled 15 times during the monitoring season. All sampling events had bacterial levels in the safe swimming range.
Freeland County Park beach had a permanent swimming advisory from June 1 through Sept. 15, due to sporadic high bacteria levels during the months that beach wrack accumulates on the beach. This beach was sampled 14 times during 2020. On July 8 and July 23, Freeland County Park had bacteria results that exceeded the safe swimming standard. Signs were already posted at the beach warning the public, since these events took place during the permanent advisory. All other sampling events resulted in bacteria levels in the safe swimming range.
During the summer, north winds cause beach wrack (decaying marine vegetation along the shoreline) to accumulate along the southern Holmes Harbor shoreline. Beach wrack can be up to two feet thick in some areas. In 2012 – 2013, the Department of Health conducted a study to determine if beach wrack could be a source of bacteria. The study showed lower levels of bacteria during the winter and spring seasons when beach wrack was not present in such great amounts. High bacteria levels during summer months may be part of a natural condition at this beach.
During the 2020 monitoring period, Windjammer Lagoon had good water quality with low bacteria levels. This beach was sampled 14 times during the monitoring season. On Aug. 6, sampling results exceeded the safe swimming standards, but subsequent sampling showed that bacteria levels had dropped into the safe swimming range. All other sampling events resulted in bacteria levels in the safe swimming range.
Data summary: Bacteria results compared to standards
The chart below summarizes the bacteria levels at Island County beaches in relation to the EPA swimming standard or saltwater swimming criteria. Beaches are considered unsafe for swimming when the geometric mean of enterococcus/100 mL of water is greater than or equal to 30 and the statistical threshold value of enterococcus/100 mL is greater than or equal to 110. We issue a public swimming advisory when enterococcus levels exceed 104 per 100 mL of water.
Table: Calculated geometric mean and statistical threshold value at Island County beaches (in enterococcus per 100 mL) for 2020.
|
Beach
|
GM
|
STV
|
|
Dave Mackie Memorial County Park
|
13
|
33
|
|
Freeland County Park/ Homes Harbor
|
24
|
109
|
|
Windjammer Lagoon
|
23
|
61
|