King County annual BEACH report

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.

During the 2017 beach season, 62 public beaches on coastlines were sampled from Memorial Day through Labor Day. High-use beaches were sampled weekly or biweekly for enterococcus, a type of fecal bacteria. High enterococcus levels are linked to swimmer illness.

King County saltwater swimming beaches

We sampled 10 King County beaches from May 22 through Sept. 1, 2017 almost every week during the swimming season.

Alki Beach Park

Alki Beach Park was sampled for 14 weeks during the swimming season. Water quality at this beach was good. On July 17, sampling results were in the swim advisory range, but subsequent sampling showed that bacteria levels had dropped into the safe swimming range.

This beach was closed to swimming due to a sewage spill on Feb. 9-10, 2017.

Carkeek Park beach

Carkeek Park beach was sampled for 13 weeks during the swimming season. Water quality at this beach was very good and met the swimming standards during all periods sampled.

Dash Point State Park beach

Dash Point State Park beach was sampled for 15 weeks during the swimming season. This beach had excellent water quality and met the swimming standards during all periods sampled.

Golden Gardens beach

Golden Gardens beach was sampled for 13 weeks during the swimming season. During the 2017 season, this beach had very good water quality and met the swimming standards during all period sampled.

The beach was closed to swimming due to a sewage spill on Feb. 9-21, 2017.

Lincoln Park beach

Lincoln Park beach was sampled for 13 weeks during the swimming season. This beach had very good water quality, meeting the swimming standards during all periods sampled.

A shoreline survey was conducted by BEACH Program staff at this beach on July 12, 2017. A recommendation was made to provide pet waste stations since people were observed walking dogs along the path above the beach.

Redondo County Park beach

Redondo County Park beach was sampled weekly during the swimming season. This beach had good water quality. On July 10, sampling results were in the swim advisory range, but subsequent sampling showed that bacteria levels had dropped into the safe swimming range.

Richey Viewpoint beach

Richey Viewpoint beach was sampled for 12 weeks during the sample season. This beach had very good water quality, meeting the swimming standards during all periods sampled.

Richmond Beach Saltwater Park beach

Richmond Beach Saltwater Park was sampled for 13 weeks during the swimming season. This beach had excellent water quality, meeting the swimming standards during all periods sampled.

Saltwater State Park beach

Saltwater State Park beach was sampled weekly during the swimming season. This beach had excellent water quality, meeting the swimming standards for all periods sampled.

Seahurst Park beach

Seahurst Park Beach was sampled for 13 weeks during the swimming season. This beach had very good water quality, meeting the swimming standards during all periods sampled.

Data summary: Bacteria results compared to standards

The chart below summarizes the bacteria levels at King 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 35 and the statistical threshold value of enterococcus/100 mL is greater than or equal to 276. We issue a public swimming advisory when enterococcus levels reach 104 per 100 mL of water.

Table: Calculated geometric mean and statistical threshold value at  King County beaches
(in enterococcus per 100 mL) for 2017