We monitored four beaches in Island County during the 2022 monitoring season:
- Dave Mackie Memorial County Park
- Double Bluff Park
- Freeland County Park, Holmes Harbor
- Windjammer Lagoon
Freeland County Park in Holmes Harbor had a swim advisory from June through mid-September, due to high bacteria levels.
Keeping beaches safe
The Beach Environmental Assessment, Communication & Health, or BEACH, Program ensures that marine water is safe to swim and play in and informs the public if water doesn't meet swimming standards. Sampling takes place from Memorial Day to Labor Day. During this time, you can check out current water quality conditions on the swimming map.
Island County Public Health sampled four Island County beaches during the 2022 season.
See details on each beach below.
During the 2022 monitoring period, Dave Mackie Memorial County Park had excellent water quality. This beach was sampled 15 times during the monitoring season. All sampling events had bacterial levels in the safe swimming range.
During the 2022 monitoring period, Double Bluff Park had one sampling event that exceeded the safe swimming standard. On Aug. 16, bacteria levels were elevated which resulted in a week-long advisory. This beach was sampled 13 times during the monitoring season, and all other sampling events resulted in bacteria 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 11 times in 2022. All 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, a study was conducted at this beach by the Department of Health in order 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 2022 monitoring period, Windjammer Lagoon had excellent water quality with low bacteria levels. This beach was sampled 15 times during the monitoring season. All 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 2022.
| Beach |
GM |
STV |
| Dave Mackie Memorial County Park |
12 |
22 |
| Double Bluff Park |
53 |
399 |
| Freeland County Park/ Homes Harbor |
15 |
29 |
| Windjammer Lagoon |
12 |
21 |