Press release from the Humboldt Bay Municipal Water District:

Before enjoying Ruth Lake this summer, be sure to Clean, Drain and Dry all watercraft including kayaks, canoes, paddle boards, rafts, boats and trailers to prevent the spread of the recently introduced aquatic invasive species, the golden mussel. The golden mussel, native to East and Southeast Asia, was first documented in California in October 2024 and is spreading throughout the Sacramento-San Joaquin Delta at an alarming rate. The golden mussel is capable of rapidly spreading, wreaking havoc on ecological health and threatening water infrastructure and quality at a much more aggressive rate than the quagga and zebra mussels.

Golden mussels easily spread to new habitats from watercraft and trailers. You might unintentionally transport their microscopic larvae in water held in your boat’s ballast tank or bilge.

Ruth Lake, impounded by Matthews Dam on the Mad River, serves as the drinking water source for the majority of Humboldt County. The dense colonization of golden mussels would threaten operations of Matthews Dam, threatening Humboldt County’s water supply. The lake is also a favorite recreational destination for Northern Californians. Access to Ruth Lake is controlled by the Ruth Lake Community Services District in partnership with the Humboldt Bay Municipal Water District. If boaters fail to take necessary precautions to protect Ruth Lake from the golden mussel, public access to Ruth Lake may be closed.

California Department of Fish and Wildlife officials say “Based on the water quality data, Ruth Lake definitely has high enough calcium levels to support golden mussel establishment if they are introduced. Ruth has the correct calcium, pH, dissolved oxygen, and temperatures for their survival and reproduction.”

“To ensure Ruth Lake remains open to recreational use, boaters must do their part to protect Humboldt County’s water source by cleaning, draining, and drying all watercraft equipment — from power boats to stand up paddle boards — prior to entering the lake,” said Michiko Mares, General Manager at the Humboldt Bay Municipal Water District.

“Across California, public access to recreational waters are being closed because of the risk of spreading golden mussels. Please be responsible to keep Ruth Lake open to our community for recreational purposes and to assure our water source is protected.”

“Before your watercraft can enter the lake, it must be inspected. Prior to arriving at Ruth Lake, be sure your watercraft is completely cleaned, drained, and dried. Inspections are available at the Ruth Lake Marina, seven days a week from 7am to 7pm or at the Ruth Recreational Campground, seven days a week from 8am to 8pm” said Caitlin Canale, General Manager of the Ruth Lake Community Services District.

Humboldt Bay Municipal Water District and Ruth Lake Community Services District are working closely with state and federal agencies and other water managers to track the spread of the golden mussel, monitor boat traffic, inspect watercraft, and prepare long-term plans in the event the golden mussel is introduced into Ruth Lake.

For any questions please call: Ruth Lake Marina: 707-574-6194

Ruth Rec Campground: 707-574-6196

Please visit the RLCSD website for more information.