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Cumulative Effects of Logging Linked to Coho Decline


Campbell Timber Management Clearcut in Ten Mile River Watershed


Throughout the north and central California coast, Coho salmon are teetering on the brink of oblivion. According to the National Marine Fisheries Service, 85-90 percent of remaining Coho population in the Central California Coast ESU occurs in watersheds with privately managed forestlands. The 2011 Central California Coast Coho Recovery Plan identifies timber harvest as an ongoing threat to the survival and viability of the species.

In 2009, the Board of Forestry and Fire Protection adopted permanent Forest Practice Rules to address the glaring deficiencies in its riparian buffers for streams and rivers bearing Coho and other listed salmonids. While these rules represent a significant step forward, the Board continues to ignore the real elephant in the room; cumulative impacts related to forest management activities.

Since the late 1990’s, the questions of how to address cumulative effects resulting from high and intense rates of harvest has lingered. The advent of the New Year’s storms of 1997 in Humboldt County that saw the unraveling of watersheds subjected to the rapacious logging of Pacific Lumber Company lead even the most conservative of State and federal agencies to stand up and take notice. In 1999, the Board of Forestry commissioned a panel of experts to study the effectiveness of the California Forest Practice Rules in protecting listed anadromous salmonids and their functional habitat.

The Report of the Scientific Review Panel on California Forest Practice Rules and Salmonid Habitat found that the primary deficiency of the Forest Practice Rules was the failure to effectively address cumulative watershed effects, and particularly called out the need for consideration of rate of harvest limitations as a mechanism to maintain and improve properly functioning aquatic habitat conditions for Coho and other listed salmonids. The Scientific Review Panel Report recommended that greater scrutiny of harvest activities be given when rate of harvest exceeds 30-50 percent of a watershed in ten years.

More recent studies conducted by Klein et al. titled Logging and turbidity in the coastal watersheds of northern California has shown a relationship between rate of harvest in a watershed and excess turbidity in those streams. Klein found that “Despite much improved best management practices, contemporary timber harvest can trigger serious cumulative watershed effects when too much of a watershed is harvested over too short a time period.” Klein further identified the lack of regulatory controls for rate of harvest impacts: “Although the rate of timber harvest has been acknowledged among scientists, regulatory agencies, and legislators as a factor contributing to declining water quality and aquatic habitat for some time, regulatory controls on harvest rate do not presently exist.”

Rate of harvest is expressed through calculation of percent canopy removal, via a clearcut-equivalent acres methodology. Klein identified that watersheds with clearcut-equivalent acre rates of harvest exceeding 1.5 percent per 10-15 years resulted in greater than 10 percent turbidity exceeding baseline water quality conditions. Recent studies such as Jensen et al. (2009) have drawn a correlation between the amount of sediment deposited in spawning gravels and decreased salmonid egg to fry survival.

In the Ten Mile River basin in Mendocino County, rates of timber harvest in some sub-basins wildly exceed the scientifically-identified thresholds where cumulative impacts to salmonids may be presumed to occur. 85 percent of the Ten Mile River basin is controlled by Campbell Timber Management Company. Since 2005, the Department of Fish and Wildlife (formerly the Department of Fish and Game) has been raising concerns over high rates of harvest and cumulative effects in sub basins of the Ten Mile River and the implications for endangered Coho.

In 2010, the Department of Fish and Wildlife inspected two Campbell Timber Harvest Plans in two Ten Mile River sub basins with high rates of harvest and again raised concerns over the potential for cumulative impacts to fleeting Coho populations. In response to these concerns, CAL FIRE hydrologist Pete Cafferata calculated the potential sediment delivery from proposed clearcuts via increases in peak flows and determined that significant sediment delivery and changes in peak flows were likely to occur. Astonishingly, CAL FIRE management determined that they could not show an impact to Coho or other listed salmonids and moved to approve the THPs. However, this process has been suspended thanks to intervention from the Regional Water Quality Control Board. The Regional Board however did not object to the high rate of harvest in the Ten Mile sub basins, but rather raised indicated that the THPs, if implemented, would violate applicable water quality requirements. In response, Campbell decided to defer harvest on clearcut units proposed in the two THPs in question, and changed from clearcutting to selection on two units. This approach, however is riddled with flaws as well.


Meanwhile, on Green Diamond Resource Company lands in Humboldt County, rates of clearcut timber harvest similarly have been shown to exceed scientifically-identified thresholds. One example of this is the Maple Creek watershed, where Green Diamond has harvested 62 percent in a 12 year period. Future projections estimate that Green Diamond will have harvested nearly 82 percent of the Maple Creek watershed in approximately 25 years. In this instance, the Regional Water Board has once again ignored the problem of rate of harvest issue in promulgating a property-wide Waste Discharge Requirement Permit for Green Diamond. EPIC has filed an appeal with the State Water Resources Control Board of the property-wide WDR permit on the grounds that the Regional Board failed to consider and address issue of rate of harvest.

The ongoing battle over rate of harvest and its influence on cumulative watershed impacts has been complicated and convoluted by both the timber industry and CAL FIRE itself working tirelessly to dismiss the applicability of the findings of Klein and others. Meanwhile, the Regional Water Board has avoided dealing with the issue entirely. Real progress towards maintaining, enhancing and restoring properly functioning aquatic habitat conditions will not be made until the agencies and the industry become willing to address rate of harvest and cumulative impacts.

EPIC provides a public service as a watchdog organization that works to protect the redwood region of the Pacific Northwest. Since 1977, EPIC has developed relationships with logging companies and regulatory agencies by commenting on timber harvest plans and the policies that regulate them to identify and address the impacts on forests, watersheds and the animals that depend on them. In the beginning, EPIC helped shape many of the critical rules to protect our wild back yard, and now we are working to see that these rules are implemented and improved where necessary. Different levels of engagement vary from phone conversations to lawsuits; taking countless hours of reading, analyzing, commenting and negotiating to keep private industry from transforming our forests into a wasteland. EPIC will keep this work up heading into 2013 and beyond.

Please help provide EPIC with the financial means to continue the fight to protect these unique forest ecosystems for future generations. The best thing you can do is make a simple donation today. This will ensure that we can continue working on your behalf, to protect the legendary redwood coast.

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