Adaptive management CMER science called Hardrock and Softrock Experimental Buffer Treatment Studies show that current forest practices rules keep non-fish and fish stream temperatures below the Dept. of Ecology’s criteria for salmon streams, below 16⁰ C, or 60.8°F. In fact Np streams are all cooler than that, at 12-14°C or 54-58°F.
Hardrock and Softrock Experimental Buffer Treatment Studies, shows timber harvesting may temporarily increase water temperatures by approximately 0.5-1°C equivalent to 0.9-1.8°F. This does not affect salmon-safe temperatures. In fact, the studies show this is a temporary effect and streams recover to their natural temperature as trees and vegetation grow back in a few years. As an extra precaution, small, and large landowners and counties propose doubling the length of buffers to a minimum of 1,000′ where it matters – upstream of the intersection where fish and non-fish streams meet, and widening the first 500’ to 75′, to ensure fish-safe temperatures are protected.
The Dept. of Ecology claims that water quality rules say there can be no temporary change at anytime, anywhere beyond 0.3°C or .54°F. Their remedy is to widen and lengthen buffers to cover the entire length of all Np streams in Western Washington. This does not recognize that stream temperature can vary by 3°C in unharvested areas. Windstorms or forest fires can cause temporary disturbances where stream temperatures warm up and then recover as trees grow back, and salmon thrive. Ecology’s 0.3°C limitation is just 10% of the actual background temperature variation in the Hardrock and Softrock studies and does not reflect what really happens in the field.
We believe the small, large landowner and county’s proposal addresses the results of the studies. This proposal increases buffer area and foregone timber value by 38% to respond to the research, and Ecology’s proposal increases buffer area and foregone timber value by 140%, for an uncertain environmental benefit. To avoid overreacting to temporary and small temperature changes, monitoring is necessary to understand temperature patterns across the landscape, particularly given the potential effects of climate change. This was anticipated in the 1999 Adaptive Management program, but initial priorities focused on site-scale studies designed to effect rule changes instead of long-term water quality monitoring
The studies focused on the temperature response of clear-cutting an entire Np basin between 30-120 acres and measuring the post-harvest temperature and amphibian abundance changes. This does not reflect actual timber harvest patterns in the field. A Before-After Control-Impact study design was used to assess the response of temperature, nutrients, drift, sediment, streamflow, shade, and litterfall to four buffer treatments. However harvesting an entire Np basin in one entry is a more intensive harvest pattern than forest managers do in the real-world. These basins are rare and the harvesting pattern is not typical of what happens in the field.
It took two years and 36,000 Np basins to identify the 17 Np basins selected for the Hardrock study which met the specific criteria of:
Once a pool of sites was chosen, the entire basin was harvested except for the four experimental buffer treatments and the Before, After, Control, Impact (BACI) approach was used to see how amphibians and water temperature responded to these extreme conditions.
In order to see how many times actual forest practices in the field have replicate these experimental conditions, we evaluated 979 Np basins over ten years (2010-2020) and found that 80-100% harvests in Np basins between 30-120 acres are not frequent, even over five to ten years it is infrequent. We found fewer than 15 basins (1.4%) of 30 acres or greater being harvested in a single Forest Practices Application over this time period.
To be responsive to the study results and avoid whole basin harvests greater than 30 acres, a continuous 75′ buffer is proposed for the entire length of the Np stream if the entire basin is harvested in a 5-year period. Most of the Caucuses agree on this proposal. To address stakeholder concerns that entire Np basins could be harvested with multiple entries, landowners and counties propose that if 85% of the Np basin greater than 30 acres is harvested within a 5-year period, a 75′ continuous buffer will be required for the full length of the Np stream.
The federal US Fish and Wildlife and National Marine Fisheries Services that approved the Forests & Fish Habitat Conservation Plan (HCP) anticipated temporary temperature changes post-harvest and rapid recovery after growth. On the other hand, the State Dept. of Ecology’s standard of no change > 0.3°C anywhere, anytime is inconsistent with the larger HCP vision.
The federal services recognized that temporary increases in stream temperatures recover within 5-15 years to pre-harvest conditions.(FP HCP Chapter 4d pgs. 239-241) Forest management over 40–60-year rotations do not create persistent and permanent change in water temperature, in fact on average minor temperature response measured in the Hardrock and Softrock studies (0.5-1°C) occurs over a relatively short period of time (3-9 years) compared to a harvest rotation of 40-60 years. When considering these findings in addition to other relevant CMER and non CMER studies, we believe the landowner and county’s proposal addresses the problem identified. (see also NMFP BiOp page 285 and USFWS BiOp page 5 and 862)
To determine the effect of harvest patterns at a landscape level across 55 randomly selected Type Np stream reaches, CMER measured the amount of canopy closure and water temperature. The average canopy closure across all sites was 82%, and median 93%. Average water temperature ~15° C under current Np buffer rules.
Temperature response post-harvest and amphibian abundance changes measured eight to nine years post-harvest are the two primary areas of concern. While there has been great focus on the measurable change temperature standard in non-fish streams of greater than 0.3° C, there has been little to no acknowledgement that most Hardrock and Softrock treatment sites were well below the 16° C designated use temperature standard both before and after harvest. All Forest Practices treatment sites in the Hardrock and most Softrock sites study were below this standard. This is great news!
Landowners must maintain a continuous 30’ equipment limitation zone along the entire Np stream length and maintain a minimum of half of the stream length with 50’ buffers along both sides of the stream to prevent water from warming to unsafe levels.
Current rules also require a minimum of 300-500’ of buffer length upstream of the intersection where non-fish and fish streams meet and protecting sensitive sites such as Np stream junctions, seeps, springs, and the Np stream initiation points with 56-ft radius buffers.
Buffers are also provided where there are potentially unstable slopes along Np streams. The studies show that with this extra protection, the actual length of Np streams buffered under current forest practices requirements is likely 65% – 70% rather than the minimum 50%.
Timber harvest of an entire Np watershed greater than 30 acres would require 100% of the Np stream to be protected with 75’ buffers on both sides of the stream – this is the treatment tested in the Experimental Buffer Studies. To recognize stakeholder concerns about multiple entries, the proposal is if 85% of the entire basin is harvested within 5-years, the 75′ continuous buffer is required.
A 75′ buffer of trees on each side of the stream is left for the first 500′ then a 50′ buffer for the next 500′ for a total of 1,000′ from the intersection of Fish/Non-fish streams to protect the transition zone and ensure cool water for fish.
Beyond the 1,000′ buffer of trees, an intermittent 50′ buffer on each side of the stream is left up to the origin of the stream, at the perennial initiation point (PIP) in addition to current sensitive site protections.
Current rules apply and landowners must maintain a continuous 30’ equipment limitation zone along the entire Np stream length and maintain a minimum of half of the stream length with 50’ buffers along both sides of the stream to prevent water from warming to unsafe levels. Sensitive sites such as Np stream junctions, seeps, springs, and the Np stream initiation points are protected with 56-ft radius buffers. Buffers are also provided where there are potentially unstable slopes along Np streams.
The studies show that with this extra protection, the actual length of Np streams buffered under current forest practices requirements is likely 65% – 70% rather than the minimum 50%.
The small forest landowner option is the same as prescription A and B except the buffer width is 50 feet and includes a management option in the outer 25 feet. This option recognizes the disproportionate economic impact to small landowners from substantive regulatory changes.
It also acknowledges small forest landowners tend to have smaller harvest units and harvest less often than large landowners. Incentivizing forest landowners to remain on the landscape, managing their forests for multiple benefits, should be a policy priority for the FPB and the State of Washington.
During timber harvesting, buffers of trees and vegetation are protected next to streams, called riparian zones, to protect stream habitat for amphibians and native fish, especially salmon and trout. Protection for buffers are part of the requirements set forth in the Forests & Fish Law and Forest Practices Regulations to protect cool water temperatures and reduce silt from entering streams keeping water clean. The law set in motion one of the largest Habitat Conservation Plans in the nation, which is a contract between the State of Washington and US Fish and Wildlife and National Marine Fisheries Services to protect fish habitat on all non-federal forests for 50-years. Buffers of trees are maintained across 9.3 million acres of Washington’s working forests along side 52,000 miles of streams on the westside and 8,000 miles of streams on the eastside of the Cascades.
From 2001 through 2021, forest landowners, including Green Diamond HCP have removed nearly 9,200 barriers to fish passage. To date, 100% of the barriers identified have been eliminated, opening nearly 6,500 miles of historic fish habitat. This success has been achieved through investments by the state, small and large private landowners of $390 million—of which private forest landowners have contributed $265 million for road improvements through 2021. Learn more at ForestsandFish.com.
When forest landowners negotiated Forests & Fish, they knew it would mean leaving more trees near the stream to provide protection for fish, water, amphibians, and other wildlife species; and they wanted to provide that protection. Negotiations resulted in larger buffers and emergency rules went into effect in 1999. There are three buffer zones that are determined by site-class, stream width and habitat type and to put protection where it is most needed — closest to the stream. Westside buffer widths are 90-200 feet with a core “no-harvest” zone = 50 feet. Eastside buffer widths are 75-130 feet with a core “no-harvest” zone = 30 feet.
The Core Zone is a no-touch buffer that extends outward from the stream for 50′ on the westside and 30′ on the eastside of the Cascades.
The Inner Zone (beginning at the edge of the Core Zone) can be managed to allow sufficient growth for healthy riparian areas.
Management activities in the Outer Zone are dependent on many complex factors and are dependent on what management occurred in the inner zone.
The buffers are designed to work together to provide protection for aquatic resources and be as economical as possible for forest landowners.
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