Storm Drains with lots of trash coming outHumboldt Baykeeper addresses water pollution on a case-by-case basis, and provides information to encourage Humboldt Bay residents to take action to address the problem of toxics in our environment. 

Historic industrial activity continues to impact the Bay along with the health of local residents and the area’s economy. Dioxin, heavy metals, petroleum products, and other contaminants persist in areas where they were used in the past, and continue to enter Humboldt Bay through storm water and ground water discharges.  Humboldt Baykeeper works to stop this ongoing problem by seeking cleanup of these sites.

One focus of Humboldt Baykeeper’s Toxics Initiative is the past use of wood preservatives at dozens of lumber mills that once lined the shores of the Bay and its tributaries. The mills used the chemical pentachlorophenol (also known as "penta") which led to the release of contaminants such as dioxins and furans. Accidental spills and illegal dumping of these chemicals resulted in soil and water contamination. For example, the former Simpson Plywood Mill, and an adjacent drainage swale that discharges directly into Humboldt Bay, was heavily contaminated by dioxins and furans. Through Humboldt Baykeeper’s Toxic Initiative, this ongoing threat to Humboldt Bay was identified, and has been the subject of clean up activities to eliminate this source of dioxin.

In 2006, Humboldt Baykeeper petitioned the State Water Resources Control Board to add Humboldt Bay to California’s Threatened and Impaired Waters list under Section 303(d) of the Clean Water Act.  As a result,  Humboldt Bay was listed for dioxin

Humboldt Bay was listed as Impaired by PCBs under Section 303(d) of the Clean Water Act in 2002, based on levels of PCBs found in fish tissue. PCBs have been demonstrated to cause a variety of serious health effects, including cancer and serious effects on the immune system, reproductive system, nervous system, and endocrine system. For more info on PCBs and their health effects, click HERE

In 2012, a statewide survey of coastal fish found the highest mercury levels in Humboldt Bay leopard shark. In 2016, the California Environmental Protection Agency funded our Humboldt Bay Mercury Assessment to study mercury levels in fish and to identify communities most at risk of exposure. Phase I of this study was completed in 2018, and Phase II was funded in 2019. 

Since Baykeeper’s 2006 success in getting Humboldt Bay designated as impaired by dioxin, sampling for this long-lasting contaminant has become common for dredging, restoration, and development projects. One recent study has revealed a major dioxin hotspot in Humboldt Bay near the Arcata Marsh. The good news is that ongoing monitoring at a former lumber mill in Eureka has shown that the cleanup brought by Baykeeper’s legal action has been effective.


Click HERE to download the article.

How we will prepare for rising sea levels is just beginning to take shape here in the Humboldt Bay region. Humboldt Baykeeper assessed sea level rise vulnerability for contaminated sites near Humboldt Bay. More than 300 contaminated sites are within 10 meters of current sea level, including more than 40 that are below 2 meters – the amount sea level is projected to rise by the year 2100.

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