Action Plan for Restoration of the South Fork Trinity River Watershed and its Fisheries
Watersheds naturally involve uncountable linkages between physical processes operating on the hillslopes and in the stream channels, biological processes (both terrestrial and aquatic), intrinsic and extrinsic environmental variables, and the influences of man's activities. Consequently, dissecting these linkages to identify limiting factors affecting the production of anadromous fish is very difficult.
This report is divided into seventeen separate chapters. Following the introduction, the first eleven deal with a suite of issues relevant to fisheries, limitations to fisheries recovery and past restoration efforts in the South Fork Trinity River basin. In the order of their presentation the chapters contain information on: 1) fish stock identification and populations, 2) in-channel fish habitat conditions, 3) landscape stability and erodibility, 4) land management issues, 5) water quality and water quantity issues, 6) fish harvest management, 7) large scale hatcheries, 8) small scale hatcheries and fish culture, 9) fish habitat improvement projects, 10) hillslope restoration projects, and 11) actions and interactions of agencies who manage the land or its resources. Each chapter generally discusses the status of our knowledge on the topic, and describes if, how and to what degree each is influencing the recovery of anadromous fish populations in the basin.
The eleven chapters describing the limiting factors for fisheries recovery in the South Fork Trinity River basin are followed by three chapters which provide information relevant to eventual restoration of the South Fork Trinity River and its fisheries. Chapter 13 reviews past research and monitoring efforts which have been undertaken in the South Fork Trinity River basin, as well as a variety of future monitoring techniques which can be employed to measure restoration efforts and to chart the recovery of the watershed and its fisheries. Chapter 14 outlines the approaches and potential benefits of initiating a locally-based "education" program. It stresses the value of a healthy fisheries in the long-term economic future of local communities in the South Fork basin.
Chapter 15 reviews other models of watershed and fisheries restoration projects which have been employed elsewhere in the Pacific Northwest. Chapter 16 summarizes results on a watershed basis, and lists recommended actions which, if implemented, will lead to recovery of the South Fork Trinity River and its anadromous fishery. Recommendations are summarized in three separate ways:
1) a recommended organizational framework for the restoration program, emphasizing local control, and a recommended technical framework for restoration based on conservation biology,
2) a listing of general action items and monitoring needs according to large sub-basin areas throughout the South Fork Trinity River basin, and
3) a listing of specific recommendations which address each of the limiting factors or issues which have been identified as contributing to the decline or continued depression of the basin's fish populations.
The recommendation section has been organized in parallel with the other chapters in the report to facilitate easy reference to topics or areas of special concern to each reader, and to enable readers to quickly locate supporting references or discussions concerning general topics which have led to each recommendation.
Finally, Chapter 17 describes the array of possible funding mechanisms which are available to support various components of the South Fork Trinity River restoration effort into the future. A broad mix of community participation, active agency support and innovative restoration funding will provide the best opportunity for completing a successful, large scale watershed and fisheries restoration program in the South Fork Trinity River basin.
The South Fork Trinity River watershed is an approximately 980 square mile tributary to the Trinity River. The convergence of the South Fork with the main stem of the Trinity River is located approximately 4 miles upstream of the community of Willow Creek, California (Figure 1-1). The South Fork is the largest, undammed, Wild and Scenic River remaining in California and was once widely known for its annual runs of wild anadromous salmonids.
Figure 1. Location map for South Fork Trinity River basin.
The objective of the South Fork Restoration Action Plan was to develop a practical, fact-based, prioritized listing of cost-effective short, intermediate and long-term projects and actions aimed at accelerating the recovery of anadromous fish-bearing stream channels and fish populations throughout the South Fork watershed. A list of five specific work elements identify some of the most obvious issues that were addressed in the development of the South Fork Action Plan.
The goal of this report is to outline appropriate land treatments, channel treatments, water conservation and pollution prevention measures, needed landuse changes, fisheries management techniques and educational programs needed to effect watershed stabilization and begin the proactive process of fisheries recovery in the most cost-effective manner possible. A CRMP organizational framework for implementing fisheries and watershed restoration has been proposed and possible funding sources are also outlined in a later chapter.
Historical impacts to the South Fork and its resources
Even prior to the construction of dams on the main stem of the Trinity River above Lewiston, California, a substantial proportion of chinook salmon production in the Trinity River Basin came from the South Fork Trinity River (CDWR, 1982). LaFaunce (1967) estimated that 11,400 spring chinook salmon and 3,600 fall chinook spawned in the basin in 1964. Winter steelhead were also extremely abundant as recently as the early 1960's (Trinity Journal 1962) but summer steelhead runs may never have been robust (Don LaFaunce personal communication). The frequency and size of coho salmon runs are not well documented, though they have been reported to migrate as far upstream as Hyampom, California (Coots 1952).
The South Fork of the Trinity River is bordered on the west by South Fork Mountain which has extremely productive forest soils but is also highly unstable and susceptible to land use disturbances (CDWR, 1982a). The 1964 flood caused tremendous soil loss in tributaries that had been disturbed by logging (MacCleery, 1974). Road failures and mass wasting, associated with roads and clearcut tractor logged areas, choked the channels of many of these tributaries. As these tributary streams delivered sediment into the South Fork, additional streamside landslides were triggered. In the most severely impacted reaches, up to 24 feet of sediment was deposited in the Lower South Fork at Hyampom, California (CDWR, 1982a).
The large contribution of sediment filled pools and reduced critical holding areas for spring chinook and summer steelhead. Suitable rearing habitat for all species of juvenile salmonids was also severely reduced (CDWR, 1982). Effects of this sediment incursion still linger in the system today (Haskins and Irizarry, 1988). Highly aggraded streambeds are subject to scour and fill during normal winter high flows, thereby limiting the survival of eggs and alevin (Nawa et al. 1990,1991). Studies by LaFaunce (1967) indicated the mainstem of the South Fork was the primary spawning area for chinook salmon prior to 1964. With LaFaunce's studies in mind, a Department of Water Resources report (1982) indicated that the smaller particle size distribution in the mainstem South Fork and associated high bedload mobility rates may be the single most significant factor limiting the success of chinook salmon spawning in the basin.
Lisle (1981) suggests frequent channel changes associated with highly aggraded stream beds, such as in the mainstem and many tributaries in the South Fork, also prevents riparian vegetation from re-establishing. Consequently, stream channels remain shallow and poorly defined which leaves little shade to keep water temperatures cool. In addition to high water temperatures, lack of cover for juveniles may also limit survival of salmonids in the South Fork. Sullivan (1989) found that fall chinook juveniles emigrating from the South Fork of the Trinity have the poorest growth rates of any run in the entire Klamath-Trinity Basin.
Currently, summer steelhead runs have both averaged less than 50 fish in recent years (Eric Gerstung personal communication). Annual spring chinook salmon runs from 1991-1993 have ranged from approximately 200-500 adults (Dean in press). In addition, fall chinook salmon counts from 1984-1990 did not seem to be rebounding (Jong and Mills in press), despite more restrictive ocean harvests imposed on commercial and sport fishermen.
While Hayfork Creek has less erodible terrain than the remainder of the South Fork basin, it also had sediment pulses that moved downstream after the 1964 flood. However, Hayfork Creek has, for the most part, sufficient channel gradient to induce scour and initiate more rapid channel recovery than the main stem. Water diversions and water quality problems, including increased water temperatures, are adversely affecting salmonid production in Hayfork Creek. Poaching may also be a factor limiting production in some tributaries to Hayfork Creek.
Extensive wildland fires burned much of the South Fork Trinity watershed in 1987 and a smaller fire burned in headwater areas near the Yolla Bolla Wilderness in 1988. The USFS deployed major resources to control erosion and to minimize sedimentation effects resulting from these fires. A monitoring program was initiated (USFS, 1990a) to measure sedimentation impacts resulting from the fire and subsequent salvage logging activities. Results from continued monitoring may provide data on the effects of post-fire salvage logging activities and result in the development of useful recommendations for the treatment of future burn areas in the watershed.
In October 1984, the Trinity River Basin Fish and Wildlife Restoration Act (PL 98-541) was passed into law by the Congress and signed by the President. The Act embodied in law an 11 point plan to restore and maintain fish and wildlife resources of the basin at levels which occurred prior to the construction of the Trinity River Diversion, Central Valley Project. While the Trinity River Basin Fish and Wildlife Program has been largely concerned with the main stem of the Trinity River, it has focused increasing attention on the South Fork Trinity River basin in recent years. As this report goes to press, the South Fork basin is in line for major restoration funding if the Trinity River Program is re-authorized.
A myriad of studies and investigations have focused on various components of the South Fork drainage basin and its fisheries and forest resources. However, few projects have accumulated all the lines of evidence and weighed them together in order to arrive at a rational, detailed approach to moving the basin, with its immense fisheries potential, towards recovery. In the broadest action plan developed to date, the California Department of Water Resources (1982) suggested a number of general action items for watershed improvement and in-stream habitat enhancement. To date, only a few of these recommendations have been implemented.
The Model Steelhead Stream Demonstration Project (Irizarry et al. 1985) is a joint effort to restore steelhead populations in the South Fork of the Trinity watershed initiated by Cal-Trout, the California Department of Fish and Game, and both Shasta-Trinity and the Six Rivers National Forests. The scope of the study was basin wide and some restoration activities funded by the USFS and the Trinity River Restoration Program have followed suggestions of the MSSDP. Success of the MSSDP would have to be considered limited, however, in that no recovery of the target species has been evident. Most of the MSSDP work projects have been aimed at in-channel conditions.
There is recent, growing recognition that effective fisheries restoration and long term recovery of large gravel-bedded anadromous fish streams, such as the South Fork and its tributaries, is directly dependent on the recovery and healing of eroding hillslopes and aggraded stream channels (Irizarry et al. 1985). If upper watershed areas are properly managed to significantly reduce sediment delivery, streams will recover to a self sustaining productive condition.
To this end, the U.S Forest Service, largely funded by the Trinity River Restoration Program, has conducted watershed inventories over much of its lands. These inventories were performed to identify existing and potential sediment sources, and to suggest treatments for erosion prevention on logged and roaded lands. The inventories completed have been of variable quality and only a small percentage of the work outlined has been completed. Some of the most erodible and unstable forest lands, especially those on South Fork Mountain, are under private ownership and have not been inventoried.
In another large watershed example, the U.S. Forest Service was successful in controlling erosion and dramatically improving fish habitat conditions on the South Fork Salmon River in Idaho (Platts and Megahan, 1975). In addition, a comparable program implemented in the 1970's, and still active today, for the Middle Fork Eel River, has been successful in rebuilding summer steelhead populations from critically low levels (Jones and Ekman, 1980). These and other programs provided useful ideas and techniques to be applied in the South Fork Trinity River Restoration Action Plan.
In less impacted watersheds, channel processes and structure have been described as partially recovered, or still largely intact. These healthier components of the fluvial system will serve as refuge basins and provide a seat of biological recovery for the remaining impacted areas of the South Fork which will take longer to once again reach a stable and productive state. It is these healthier components of the natural system that will provide a pool of viable native stock to re-invade the main stem and other tributaries as they begin to recover, and are able to support larger anadromous populations. Such "refuge streams" were sought out and identified during the watershed assessment process.
It is imperative that in a basin as large and as complex (diverse) as the South Fork, a helter-skelter approach to watershed recovery and fisheries restoration be strictly avoided. As has been clearly demonstrated in the past, isolated projects that are not part of a prioritized plan, or that do not take into consideration processes occurring throughout the entire basin, run the high risk of being overly costly and/or totally ineffective. For example, it makes little sense to apply treatments to a channel or to introduce native stock to a drainage network that continues to be plagued by excessive and uncontrolled sedimentation from upland areas.
Future logging and road construction on stable portions of the watershed need not be at odds with the restoration and maintenance of highly productive anadromous fish bearing streams. Improved landuse practices conducted in concert with directed erosion control and erosion prevention work on existing disturbed areas, as well as fisheries restoration projects in the channel system, can lead to long term watershed stabilization, stream channel and habitat recovery and the coexistence of both landuse and native fisheries resources. Public acceptance of the value of a productive, wild fisheries resource can also provide the necessary incentive to protect, enhance and maintain the watershed's capability to support healthy runs.
Specific topics contained in the Action Plan
The major topics addressed in the South Fork Restoration Action Plan include the following subject areas. Analysis of literature, interviews with working professionals and local residents, field evidence and inspection of unreported data has been used to formulate conclusions on each of the topics related to limiting factors and possible restoration tools.
Major limiting factors were identified in different sub-basin areas to help prioritize restoration recommendations and actions using the following baseline information: historic habitat information, recent habitat typing surveys and reports, past and present utilization of habitat by salmon and steelhead in the basin, evaluations of recent habitat improvement projects, reports on past and future land use activities and impacts, watershed inventories, consultations with fisheries and watershed professionals and review of hatchery harvest management approaches.
Existing watershed inventories and assessments for the South Fork basin conducted by Six Rivers National Forest and Shasta-Trinity National Forests were thoroughly evaluated. We reviewed the inventory work and the resultant restoration proposals and treatments for erosion prevention, erosion control and fisheries restoration to be carried out where work was identified. Cost-effectiveness and effectiveness data was scrutinized for each type of restoration strategy and project.
Ongoing and past land management practices have been evaluated for both private and public lands, with special emphasis on forest management practices and water withdrawals for agricultural purposes. We have reviewed and suggested appropriate changes in land management practices for sub-basin areas or highly erodible/unstable terrain to decrease sediment input into the South Fork and its tributaries, and thereby allow channel recovery. We have also included recommendations for restoring summer flows to Hayfork Creek while still providing sufficient water for needed irrigation in the valley. One goal of water conservation is to permit establishment of a refuge area for summer steelhead and spring chinook from Rusch Creek downstream to the mouth of Hayfork Creek.
The potential of using small scale hatcheries to recover runs of native salmon and steelhead in the South Fork Trinity River Basin has been reviewed. Suggestions are made as to: potential sites for weirs to capture adult broodfish, methods of handling of adults to minimize mortality, guidelines for avoiding loss of genetic diversity, potential sites for hatcheries, approximate costs for such facilities, and monitoring strategies to determine effectiveness and potential side effects. Fisheries harvests outside the South Fork Trinity River Basin have been identified as possibly impeding recovery of the basin's salmon stocks. We have outlined the problems with mixed stock ocean harvests and in-river fisheries and suggested solutions that the Trinity River Task Force or others might pursue with the Klamath Fisheries Management Council and the Pacific Fisheries Management Council.
To implement the broad variety of recommendations and restoration action items identified for the basin, we have suggested the formation of a community-based decision-making group acting through a Coordinated Resources Management Plan (CRMP). It will be important to build local community support for the fisheries restoration actions outlined in the final plan. This can best be done by developing a sense of ownership in the plan's findings and recommendations, and by increasing awareness of the economic development benefits of restoring salmon and steelhead to the South Fork basin. With broad-based community support, fisheries protection and locally based restoration efforts are likely to continue long after the Trinity River Restoration Program has ended. Although initial funding for CRMP organization, staffing and pilot restoration are likely to come from the Trinity River Restoration Program, a host of other potential funding mechanisms for restoration have also been identified.
Methods, tasks and project phases
Development of the South Fork Restoration Action Plan involved five basic work tasks. These five tasks were performed in three (3) main project phases, culminating in a final action plan for the South Fork.
1. Locate and compile existing information. Existing, relevant information on the South Fork watershed and its resources were assembled from a variety of sources, including: a. published data, reports and papers (agency and private), b. unpublished reports, studies and internal documents, c. analyses and opinions of locally experienced professionals, d. public knowledge and observations (through scoping) and e. field observations.
2. Systematic cataloging and presentation of data. The information and documents were collected and compiled, including development of a computerized database allowing for key-word access to fisheries, watershed processes and restoration information available for the South Fork Trinity River and its sub-basins. The most important documents and information in the database have been annotated, referenced and located for future use by any interested resource managers, resource specialists, and concerned public citizens.
3. Analysis and evaluation of compiled data. Data, personal and professional observations, descriptions, findings, conclusions and recommendations covering all or a portion of the South Fork and its tributaries were analyzed. The sources of information were reviewed for their applicability, quality of information, thoroughness, and usefulness in documenting watershed and fisheries resources, and in assisting in the development of possible restoration strategies. The goal of the analysis was to determine those factors which appear to be limiting the rapid recovery of South Fork fisheries.
4. Preparation and presentation of findings and conclusions. Findings and conclusions were then developed concerning the status of in-stream habitat, fish populations, prior restoration efforts, watershed conditions and the effects of various land management activities. These findings have been described generally for the entire South Fork Trinity River basin, and more specifically for those sub-watersheds and segments of the mainstem where reliable, quality data and information exists. Conclusions range from "specific" (in well studied and analyzed portions of the basin), to "general" (where data is less quantitative or less abundant).
5. Development of recommended restoration strategies. Strategies were developed as the culminating product of the intensive review of existing data, research documents, management reports, personal interviews and field observations. Water management, watershed management, forest management, fisheries habitat improvement projects and bioenhancement were all reviewed as possible tools for restoration of fisheries resources in the basin. Specific recommendations for sub-basins were developed and tailor-made to assist in the maintenance or restoration of fisheries resources.
In Phase 1 of the project, staff located, assembled and compiled all existing, relevant information developed for the watershed over the last several decades. These include published data, reports and papers from both agency and private sources; unpublished reports, studies and internal documents that may not be readily available or known; analyses and opinions of locally experienced fishery, watershed and landuse professionals; as well as public knowledge and observations of watershed and fisheries conditions (and practices) obtained through a public scoping and interview process.
Agencies that had considerable information, concerns or responsibilities for fisheries resources or water quality in the South Fork are numerous, and each was involved in delimiting both the problems, available data and the potential solutions to depleted fisheries resources in the basin.
Phase 2 work consisted of analyzing and evaluating all compiled data, personal and professional observations, interview and personal contact information, written descriptions, findings, conclusions and recommendations. The goal of the analysis phase was to specifically outline those factors which appear to be limiting the rapid recovery of South Fork fisheries. This analysis and synthesis process focused on a variety of issues including water quality and pollution, a broad range of fishery restoration and management issues (eg, habitat improvement, rearing programs, and harvests (including poaching), watershed management and landuse practices, and watershed stabilization opportunities throughout the basin. These findings represent the best available information regarding the status of the watershed and its fisheries, and form the basis for the recommended South Fork Restoration Action Plan completed during Phase 3 work.
In the final step, Phase 3, recommended strategies for watershed restoration and fisheries recovery were developed from the intensive review of existing data, research documents and management reports. Water management, watershed management, forest management, fisheries management and physical restoration were all reviewed as possible tools to be included in the recommended restoration action plan for the South Fork basin. Recommendations have been divided into those that are likely to have the most immediate, beneficial effect on fishery restoration for the South Fork, and those that will be required for long term, complete recovery of the resource.
The basic guiding premise in prioritizing recommended tasks has been to first perform those tasks that are absolutely necessary to retain viable stocks. These include in-stream or watershed treatments, the delineation and protection of critical habitat refugia, or implementation of a lifeline program of small scale rearing using a native stock base. This action will help assure that native fish stocks will be present when the benefits of other restoration projects have improved watershed conditions. This is a critical first-step.
From that point, the most effective and most cost-effective techniques have been integrated in a prioritized action agenda. These include a wide variety of recommendations with the most beneficial and most cost-effective tasks to be performed first. The identification of key watershed refugia, restoration potential and treatment cost-effectiveness largely rule which sub-watersheds are proposed for treatment first, and which become part of the long-term recovery program. Those sub-basins that have the greatest potential for immediate recovery and protection of native stock with the least amount of expenditure have become the highest priority targets for initial action.
There are a variety of other action recommendations that do not fall into the category of instream or watershed restoration. These include institutional changes which result in altered policies or regulations; changes in land management patterns or landuse activities which will accelerate watershed recovery; and social changes brought about through education and information programs. We envision concurrent implementation of these social, institutional and educational programs with the physical and biological restoration tools that are recommended for the basin. They will be on-going, evolving programs that draw the community into the restoration effort.