Water Quality

Since 2005, our Water Quality Program has documented conditions of local streams and sloughs to identify problem areas for future monitoring and to pinpoint pollution sources so we can work to reduce or eliminate them. Thanks to the dozens of dedicated volunteers and partners who help make our program successful!

6PPD-Quinone in Urban Streams of Humboldt Bay, Lower Eel River, and Mad River Watersheds

In 2020, 6PPD-quinone, the breakdown product of the tire preservative 6PPD, was identified as a major contributor to Urban Runoff Mortality Syndrome in the Puget Sound watershed, where adult Coho Salmon often die before spawning in areas with high concentrations of road runoff. Since then, studies have been done in San Francisco Bay, but little information is available beyond major metropolitan areas. This study is the first to examine concentrations of 6PPD-q in Humboldt County.

Photo: Alex Juan sampling Jolly Giant Creek in Arcata for 6PPD-quinone. Photo by Audrey Jackson, Wiyot Tribe Shawir Darrudaluduk.

Testing for Toxic Tire Chemicals

In 2020, a stormwater contaminant was linked to "urban runoff mortality syndrome" in Coho salmon in the Puget Sound, Washington. 6PPD is an anti-wear chemical added to tires and other rubber-based products to increase the life of the tire and prevent degradation. When our tires wear down from friction with the road, they leave behind tiny particles, which can be washed from roads into aquatic ecosystems by rain. These particles bring with them all the various chemicals and compounds added to tires, including 6PPD. As 6PPD is exposed to ozone in the air, it is transformed into 6PPD-quinone (6PPD-q), which is highly lethal to Coho salmon.

Photo: This bioswale was installed on the Cal Poly Humboldt campus along LK Wood Blvd. to intercept stormwater runoff from the Library Circle parking lot.

Moonstone Beach Bummer

Last month, Moonstone Beach ranked as the sixth most polluted beach in the state on Heal the Bay’s Beach Report Card. This annual report compares water quality at recreational beaches throughout California in terms of fecal bacteria. Most concerning to swimmers and surfers are sewage spills, but these pathogens also live in the guts of livestock, pets, and wildlife, and are often flushed into streams and the ocean by rainstorms.

EcoNews Report: Clam Beach Pollution Mystery Solved?

Clam Beach landed on Heal the Bay's list of California's most polluted beaches yet again this year, getting an 'F' for water quality on the 2021 Beach Report Card. This episode of EcoNews Report features Dr. Jeremy Corrigan, who has worked for years to answer the burning question: why does Clam Beach have such high levels of fecal indicator bacteria? Dr. J is the Lab Manager at the Humboldt County Dept. of Public Health, and recently published a paper based on genetic analysis of the most likely sources. His findings point to birds as the main influence at Clam Beach, while cattle appear to be the biggest source of bacteria pollution in the Strawberry Creek watershed. Tune in to find out what this means for surfers and other beachgoers.

Clam Beach Pollution Study Points to Birds

Clam Beach has been on Heal the Bay's “Beach Bummer” list of California's most polluted beaches for years, getting an 'F' for water quality on the latest Beach Report Card.

But after years of research, we now have a better sense of the source of this pollution thanks to a new study by Humboldt County's Public Health Lab Manager, Dr. Jeremy Corrigan.