18—
INTEGRATED APPROACHES TO RIPARIAN MANAGEMENT
ARE THEY SUCCEEDING?
Developing a Long-Term Protection Plan for the McCloud River, California[1]
Thomas F. Hesseldenz[2]
Abstract.—The McCloud River drainage in northern California hosts the Dolly Varden char (Salvelinusconfluentus ), Shasta rainbow trout (Salmo gairdneri ), redband trout (S . campi ), Shasta salamander (Hydromantesshastae ), and Shasta eupatory (Eupatoriumshastense ). These species and numerous others with rare or threatened status have until recently been indirectly protected by a history of private ownership and inaccessibility of large parts of the drainage. Dam construction, water diversion, road construction, timber harvest, angling pressure, and limestone quarrying now threaten the drainage and have encouraged intensive planning efforts to lessen their impacts. However, integrated planning using a system-wide approach has been complicated by multiple ownership and agency involvement in the drainage. The Nature Conservancy through the McCloud River Preserve is seeking to resolve this problem with its McCloud River Protection Plan. The tentative components of this plan are presented in detail.
Introduction
Environmental planning has come into its own as a discipline in the last few years. Aiding in this evolution have been various governmental mandates; most notably the National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA). We are finally seeing proposed actions with potential environmental impact being preceded by thorough studies of the affected system. However, the preservation of the integrity of a whole system as an end in itself is rarely the direct object of planning efforts. Achieving such an end is often complicated by multiple ownership and agency involvement. Such is the case on the McCloud River in northern California, where The Nature Conservancy (TNC) owns the McCloud River Preserve (the Preserve).
Ownership in the McCloud drainage includes private individuals, fishing clubs, and timber companies as well as Pacific Gas and Electric Company, USDA Forest Service (FS), and TNC. The California Department of Fish and Game (DFG) is also deeply involved with the wild trout fishery there. Each entity has its own recognized values of the drainage, its own goals, and its own planning program to achieve these goals. TNC, through its involvement with the Preserve, is in the position of being able to work towards the preservation of the integrity of the McCloud River drainage as its primary goal. With such a goal, the system will come first; the challenge will be to integrate the activities of the other entities involved and direct them towards this goal.
Work has only just begun on this planning effort, known as the McCloud River Protection Plan. The details behind this plan are presented at this incomplete stage so that they will be available at an earlier date to other planners dealing with whole systems. The author hopes this timing will also generate suggestions which may improve the planning efforts of TNC in the McCloud River drainage.
Description of the System
The McCloud River drainage is located in Shasta and Siskiyou counties in northern California, in a region where the Sierra Nevada, the Cascades, and the Klamath Mountains intersect (fig. 1). The McCloud River originates in the relatively flat volcanic region southeast of Mt. Shasta. From there it flows westward through extensive yellow pine (Pinusponderosa ) forest for about 40.2 km. (25 mi.) as a large stream.
[1] Paper presented at the California Riparian Systems Conference. [University of California, Davis, September 17–19, 1981].
[2] Thomas F. Hesseldenz is Preserve Manager for the McCloud River Preserve of the Nature Conservancy, San Francisco, Calif.
Figure l.
Map of the portion of the McCloud River drainage being evaluated in the McCloud River
Protection Plan, showing significant geographic features and property ownership.
Shortly after descending three large waterfalls, the lowermost being the historic barrier to upstream fish migration, the McCloud greatly enlarges in size due to input from several large springs. These springs, thought to emerge from the collapsed terminus of a lava tube, are a constant 43°F (6.1°C) and have a summer peak flow, in contrast to winter and spring peak flows of the upper McCloud River. The downstream result is a relatively constant flow and large volume of very cold water year-round.[3]
Mud Creek enters the McCloud River about 3.2 km. (2 mi.) below Big Springs, carrying a heavy load of very fine glacial silt and volcanic ash from Mt. Shasta. This imparts a turquoise-gray turbidity to the river. Below Mud Creek, the McCloud River enters a rugged mountainous region of actively uplifting sedimentary and metamorphic rock, considered to be part of the Klamath Mountain geomorphic province.[4] Prior to dam construction, the lower McCloud flowed swiftly through its steep canyon for about 80.5 km. (50 mi.) before joining the Pit River and then, a few miles downstream, merging with the Sacramento River.
Chinook salmon (Oncorhyrchustshawytscha ), silver salmon (O. kisutch), and steelhead trout (Salmo gairdneri ) migrated yearly up the McCloud River as far as Lower Falls to spawn. The eggs, young, and carcasses of these species plus the stable large flow of cold water and habitat complexity provided by numerous boulders and deep pools are thought to explain why the interior Dolly Varden char (Salvelinusconfluentus ) has persisted in the McCloud River as a relict species. The McCloud is the southern limit of its range and the only river in California where the Dolly Varden occurs. The McCloud River strain of rainbow trout, also called the Shasta rainbow (Salmogairdneri ), may be genetically unique and has gained recognition among trout hatcheries and anglers worldwide (Sturgess and Moyle 1978).
Flanking much of the lower McCloud River are large limestone outcrops of the Baird Formation. This limestone formation has gained recognition in scientific circles for the numerous extinct mammal bones found in several of its caves and for two species endemic to both its outcrops and those of the nearby Hosselkus Formation, the Shasta eupatory (Eupatoriumshastense ) and the Shasta salamander (Hydromantesshastae ).
Downstream from Big Springs, the river is joined by numerous tributaries with high channel gradient and cool water shaded by dense riparian vegetation and steep canyons. Squaw Valley Creek is the largest of these and ranks in size among small rivers. This stream originates near Mud Creek on Mt. Shasta and, similar to the upper McCloud, flows through the relatively flat volcanic region around the town of McCloud before entering steep, mountainous terrain and joining the lower McCloud River. Haskins Creek is a large tributary to the lower McCloud which may now play the role of the functional headwaters of the river due to its position as the most upstream tributary below a major diversion dam.
The riparian zones of the McCloud River drainage form a complex assemblage of strips along headwater and tributary streams, vertical borders of waterfalls, lush growth around springs (both volcanic and limestone), oasis-like seeps often high on slopes, "dry" lakes and sinks, and large streamside flats interspersed with narrow gorges along the main river and lower Squaw Valley Creek. These large flats host numerous Wintu Indian archeological sites.
Researchers on the Preserve have noticed a much higher number of plant, avian, and mammalian species in these areas than elsewhere.[5], [6], [7] Some plant species (e.g., Abiesconcolor ) exhibit a southern range extension here, apparently due to cold air drainage associated with the cold water and steep canyons. Numerous heavily used animal trails link riparian areas to the uplands via the spines of ridges. On the Preserve, the riparian zone along the river has recently been the site for numerous deer kills by mountain lions.
History of the System
The Wintu Indians were the original inhabitants of the lower McCloud drainage, relying in part on the anadromous fishery for sustenance. While adjacent drainages were being altered by transportation routes and the search for gold in the late 1800s, the McCloud remained intact.
Central Pacific Railroad acquired the first ownership in the drainage, consisting of a river corridor and surrounding checkerboard ownership of sections. However, construction of a railway along the river never came to pass. By this time the fame of the McCloud River's wild trout fishery had spread to San Francisco, and the river corridor property was quickly bought up by pri-
[3] Data on file at the USDI Geologic Survey, Redding, Calif.
[4] Haskins, D.M. 1981. Slope stability hazards and water quality effects: proposed Ah-Di-Na timber sale. Unpublished report. Shasta-Trinity National Forest, Redding, Calif.
[5] Patterson, C. 1975. Vegetation survey: McCloud River Preserve. Unpublished report. The Nature Conservancy, San Francisco, Calif.
[6] Hayes, M. 1975. Report on the avifuana and herpetofauna: McCloud River Preserve. Unpublished report. The Nature Conservancy, San Francisco, Calif.
[7] Hayes, M., and P. Kraai. 1975. Report on the mammals of the McCloud River Preserve. Unpublished report. The Nature Conservancy, San Francisco, Calif.
vate individuals and fly-fishing clubs. Land ownership is shown in figure 1. An egg-taking station was installed a few miles up from the confluence with the Pit River, and the McCloud River rainbow trout was introduced to streams around the world.
The first major change to the McCloud drainage came in the form of Shasta Dam, completed in 1945, which blocked anadromous fish migration and inundated about 24.1 km. (15 mi.) of the lower river. Upstream, the impact was more ecological than visual; the pristine qualities of the McCloud River drainage remained unaltered until its downfall in the early 1960s. At that time Pacific Gas and Electric Company built a reservoir to divert most of the McCloud's flow to the Pit River drainage for hydroelectric production. An extensive system of roads was constructed, and much of the land around the reservoir was logged. The FS subsequently acquired about 8.0 km. (5 mi.) of riverfront property below the reservoir and installed a campground. The new road system and public ownership along the river brought a drastic increase in angling pressure to which DFG responded by stocking the river with hatchery trout. The Dolly Varden char population rapidly declined until it was thought to be extinct in the McCloud River.
Impacts on the riparian zone of the river were substantial. Aside from inundating 8.0 km. (5 mi.) more of river, McCloud Reservoir drastically reduced the annual flow downstream. Most Douglas fir (Pseudotsugamenziesii ) and western red cedar (Thujaplicata ) trees growing within the riparian zone died, supposedly due to a root rot epidemic.[8] Alders and willows colonized the banks and gravelbars previously scoured by annual floods. The exotic black locust (Robiniapseudoacacia ), first introduced at a homesite upstream, likewise responded to this available habitat and spread downstream. The streamside plant Peltiphyllumpeltatum began blooming in April instead of June. Beavers began to lodge along the river where they had probably probably been excluded by regular floods in the past.
To complicate this situation, extensive logging and associated road-building increased sediment input. Fortunately, the soils in the McCloud drainage are fairly resistant to mass failure, and the problems found on the Trinity River and Redwood Creek have not yet developed there. However, due to a relatively low channel gradient and reduced flows, the river may not be able to flush out the sediment. This in time could lead to streambed aggradation with associated bank erosion (Seidelman 1980). Fine sediments cloud the river during large rainstorms; this may affect spawning gravels and aquatic invertebrates.
This was the state of affairs when TNC acquired the Preserve in 1973. The McCloud River Club, one of the large private owners, donated 943 ha. (2,330 ac.) of their land, including 10.5 km. (6.5 mi.) of river. The gift was gladly accepted by TNC, which was well aware of the recent and rapid decline in riverine systems throughout the state.
Critical Elements
Natural diversity may be thought of in terms of the units that comprise it. These are here called "elements" of natural diversity, the building blocks of uniqueness in any natural systems. Many of the elements found in the McCloud River drainage are now considered to be critically threatened. Table 1 lists those critical elements that have been identified to date. Many of these elements do not depend solely on the McCloud region for their continued survival, but since they have been recognized as worthy of concern, they are listed here for the sake of completeness. TNC is primarily concerned with those taxa of proven or potential genetic uniqueness which are restricted in distribution to the McCloud region, as well as those of such critically threatened status as to have received state and/or federal legal recognition.
Current and Potential Threats to Critical Elements
Current and potential threats to the critical elements of the McCloud River drainage include dams, timber harvest, public-use pressure, limestone quarrying, and ignorance. Dams are by far the greatest threat. As mentioned above, these have already resulted in inundation, streamflow and temperature regime alterations, blockage of spawning runs, and to the riparian zone. In the future they may result in stream channel aggradation. The Bureau of Reclamation (BR) and the California Department of Water Resources (DWR) have begun a joint feasibility study to evaluate the proposed enlargement of Shasta Lake's water storage capacity. One proposal is to raise the existing lake by 61 m. (200 ft.). This would inundate 9.7 km. (6 mi.) more of the McCloud River. An alternative to this may be to construct more dams upstream from Shasta Lake, which could involve both the lower McCloud River and lower Squaw Valley Creek.
Timber sales on FS lands in the drainage continue to be planned, and some involve large expanses of old-growth forest adjacent to or near the Preserve. The greatest threat is new road construction which may lead to increased sedimentation, habitat disruption, and undesirable public access. Existing roads in the drainage, especially those adjacent to streams, are already contributing a considerable amount of sediment to the river during storms.
[8] Kunkel, G. 1975. Cryptograms of the McCloud River Preserve: a floristic study. Unpublished report. Department of Botany, University of California, Davis.
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The FS has made significant attempts to minimize logging impacts by placing roads high on slopes and ridges, using cable logging on steep slopes, and establishing wide buffer strips along streams and inner gorges. The FS has also been very receptive to TNC concerns and to public input, and is willing to approach timber sale planning as a cooperative effort. Nevertheless, timber values are still ranked higher than ecological and recreational values in the drainage, which makes attempts to establish a sizeable special management area along the river very difficult. One sale has just been approved, another is on the verge of approval, and three more are being planned. One of these latter sales, the Beetle-Dee Sale, could involve up to 48.3 km. (30 mi.) of new roads and the harvest of 50 million board-feet of old-growth timber near the Preserve.
Related to this is the progress of the second FS Roadless Area Review and Evaluation (RARE II). Two large roadless areas were identified along the lower McCloud River, and both have been recommended by the FS for non-Wilderness status. One of the areas, which includes all of lower Squaw Valley Creek drainage, was included in a recent California Resources Agency lawsuit against the FS. This effectively stalled planning on two timber sales, but neither roadless area has been included in any of the pending Congressional wilderness bills.
Timber harvest on private lands has occurred recently both on ridges just upstream from the Preserve and near the river a few miles upstream from Shasta Lake. New roads have been completed for harvesting in two large tributary drainages below the Preserve. Timber harvest plans must be filed with the DFG, but the public review period is both brief and poorly advertised.
Public-use pressure comes mainly from anglers. Impacts on the fishery were significantly reduced between McCloud Dam and the lower boundary of the Preserve by recent inclusion of this section in the state's Wild Trout Stream program. The remaining sections of river between Lower Falls and Shasta Lake are on private land where
angling pressure is minimal. Tributaries are not included in the existing Wild Trout Stream section, of which Hawkins Creek and lower Squaw Valley Creek are the main concerns. The former has easy public access and may function as an important spawning area due to McCloud Dam; the latter stream is on FS land where vehicular access may soon become possible. Other forms of public-use pressure include hunting, camping, and hiking (notably along the Pacific Crest Trail which crosses both the lower McCloud River and lower Squaw Valley Creek).
Riparian zones receive the brunt of the traffic from this public use. Wild Trout Stream designation did not alleviate this problem since its regulations only apply to the fishery. On the Preserve, impacts are minimized by limiting the number of visitors to the Preserve at any one time, maintaining well-marked trails, and prohibiting camping.
Limestone is being quarried by the Flintkote Company at the southern tip of the Baird Formation. The Shasta salamander occurs there, and the company has set aside a portion of its land for the salamander's preservation.[9] Flintkote does not anticipate running out of limestone at their present site for many years, but the threat of new mining claims remains.
A very serious threat to the McCloud River drainage is the relative lack of scientific investigation and public knowledge. The Shasta salamander was described in 1953 and the Shasta eupatory in 1958; both dates relatively recent when compared to investigations elsewhere in California. Hayes[6] indicated that an undescribed species of slimy salamander may exist on the Preserve, and Moyle (1976)[10] feels that the taxonomic status of the McCloud strain of rainbow trout is still uncertain. Range extensions for the Shasta salamander and Shasta eupatory have recently been made, and a documented sighting of a wolverine was made in 1980.[11]
Recreational and aesthetic qualities of the drainage, beyond the angling experience, are virtually unknown to most of the public; 70% of the Preserve visitors come to fish and many of the rest are just "tagging along." However, although the drainage is being exploited for its timber and water without much resistance because of this scientific and public ignorance, it stands to suffer the impacts of increased public use should more people learn of its biological and recreational qualities. The latter situation would seem to be the lesser of two evils.
Initial Planning Reports
In the early years of TNC, critically threatened areas were considered protected once they were acquired. Extensive stewardship programs including both restoration and long-term preservation strategies were not developed. Furthermore, no attempt was made to identify and protect whole systems. As the ecological health of many preserves continued to decline from unchecked consumptive public use, lack of restoration, and impacts from surrounding land uses, TNC began to place a greater emphasis on stewardship. This is reflected in the evolution of preserve planning efforts.
The Preserve was acquired at a time when the value of stewardship planning was finally beginning to be recognized. As a result, the first step after acquisition was to make an extensive inventory of the Preserve to determine the presence and status of critical elements and recommend management strategies. Initial action was taken in the form of implementing protective fishing regulations, and a management program including limited public use was begun in 1976. The results of the inventories and inititial management experiences were incorporated into a master plan in 1978, which included a brief introduction to the region, summaries of research findings, and recommendations regarding management.[12]
The management recommendations of the master plan were subsequently implemented, but beyond this the plan had no further practical value. In fact, its title was a misnomer. The need still existed for a long-term, drainage-wide comprehensive plan which described the critical elements and their threats in detail and then proposed specific stewardship strategies which addressed: 1) the protection of the critical elements beyond the existing preserve boundaries; 2) restoration and long-term preservation of these elements on the Preserve; 3) the need for scientific research, baseline studies, and monitoring of long-term changes in the critical elements; 4) public use and education; 5) administrative concerns; and 6) financial support. This need was met by the nation-wide development of preserve preservation plans (PPPs), which were to be renewed on a five-year basis. The 1984 PPP for the McCloud River Preserve was completed in 1979.[13] Each year applicable strategies are taken from this document and included in an annual plan which is the day-to-day guiding tool of preserve management on the McCloud River.
[9] Besecker, R.L. 1979. Personal conversation. Flintkote Company, Calaveras Cement Division, Redding, Calif.
[10] Moyle, P. 1976. McCloud River Preserve: biology and management. Unpublished report. Department of Wildlife and Fisheries Biology, University of California, Davis.
[11] Bacon, M. Personal conversation. USDA Forest Service, Shasta Lake Ranger District Office, Mountain Gate, Calif.
[12] Sheppard, J. 1978. McCloud River Preserve master plan. Unpublished report. The Nature Conservancy, San Francisco, Calif.
[13] Hesseldenz, T., and S. Gordon. 1979. 1984 preserve preservation plan for the McCloud River Preserve. Unpublished report. The Nature Conservancy, San Francisco, Calif.
On the brink of becoming buried under a heap of planning documents, one last plan was found necessary. The 1984 PPP could not adequately address the subject of protection because of lack of sufficient data. The importance and complexity of this subject warranted the development of a separate protection plan for the McCloud River drainage.
The McCloud River Protection Plan
Although various ideas for protecting the McCloud River drainage have been floating around for several years, actual work on a protection plan was just begun this year. As such, much of what is discussed below is still tentative; it is presented to illustrate the approach being taken. A draft of the plan will be ready for circulation to concerned agencies, clubs, and individuals in mid-1982, and their responses will be incorporated into a final draft by the end of that year.
The McCloud River Protection Plan will consist of three phases: identification, prescription, and implementation. The identification phase, which has already begun, initially involved the establishment of tentative boundaries. In the case of the McCloud River, watershed boundaries from the McCloud Dam to Shasta Lake were initially used to define the major area of concern. The dividing line between logged-over publicly accessible lands and old-growth gated lands roughly coincides with the transition from gentle volcanic to rugged uplifted topography, and provides a useful boundary between lower Squaw Valley Creek and the rest of the drainage, which extends all the way to Mt. Shasta.
The lands around and upstream from McCloud Reservoir have been severely logged, yet the river from Upper Falls to the head of the reservoir is of major concern. Dolly Varden char may extend upstream as far as Lower Falls, and the stretch of river from Big Springs to the reservoir represents the only remaining segment of large unaltered flows. Here the tentative boundary lines define a corridor along and including the river. Gentle topography, extensive logging, limited recreational potential, and lack of many critical elements of the McCloud River above Upper Falls suggest that consideration there be limited to protection of water quality and the redband trout.
Having established tentative boundaries, the pattern of ownership was determined (fig. 1). The majority of the land is owned by the FS. Most of the riverfront property is private. In addition, many sections of land below McCloud Dam are privately owned by large timber companies in a checkboard pattern. Upstream from the dam, most of the land is owned by the Hearst Corporation. Information on private lands obtained at the Shasta County Tax Assessor's Office includes parcel size and location, ownership, assessed value, and ownership of timber or mineral rights. This is the current level of progress made on development of the protection plan. The next step will be to gather information on each parcel regarding past alterations, presence and status of any critical elements, current and potential threats, and the owner's plans for the property and receptivity to TNC objectives. Similar information will be assembled regarding FS lands.
Once all pertinent information has been gathered in the identification phase, private parcels will be assigned priorities, and alternative protection techniques will be prescribed. Priority will be determined by location, ownership, critical elements, and threats. Parcels closer to the river will probably have higher priority, and those along the river and closest to the existing Preserve will have highest priority. Parcels of land in major tributary drainages will probably rank higher than those along ridgetops away from stream channels. Those parcels strategically located to either maintain the integrity of a large area of native environment or provide a buffer between such an area and disruptive activities will have a higher priority. The distributions of critical elements will play a vital role in establishing priority.
TNC has developed many successful methods of protecting private land. In the McCloud drainage the methods being considered are acquisition by either purchase or donation, conservation easements, management agreements or negotiations, land exchanges, inclusion within protective governmental systems, and no action. Acquisition may in some cases involve mineral or timber rights where the owners of these rights are different than the landowners. In the event that an owner does not wish to sell, an arrangement, termed "rights of first refusal" may be agreed upon, by which TNC is given the opportunity to match any offer made if the owner decides to sell at a later date. A conservation easement is attached to a deed and may apply only to a particular portion of a parcel, such as a river corridor.
A less permanent method of protection is a management agreement, which is made with the present owner and remains in effect until the land changes ownership. If all else fails, specific negotiations can be made regarding land-use activities as they arise. In the case of a timber harvest on private land, the owner must file a timber harvest plan with the state; the plan is then made available for public comment.
From the point of view of the FS, private inholdings, especially those in a checkerboard pattern, present serious management problems. In response, the FS has been exchanging equal or better land on the fringes of national forests with these inholdings. Such land exchanges can be beneficial to TNC as well, by maximizing land-use planning based on ecological/geographic units rather than on often ecologically meaningless property boundaries. TNC may negotiate for direct land exchanges between private owners and the FS or may acquire land and subsequently transfer it to the FS.
Land stewardship philosophy varies sufficiently between TNC and the FS to warrant retention of ownership of the existing Preserve, but in less critical parts of the drainage (e.g., away from the river), the two agencies may be able to negotiate successfully. It is to the advantage of TNC to retain ownership over as little land as possible in order to allow the most efficient use of its limited resources.
Several governmental land status designations could influence activities on private lands and thereby serve as protective methods. Wilderness Area designation would prohibit timber sales and dam construction, but would also drastically increase public-use pressure. The same is true for Wild and Scenic River designation. Furthermore, this status only involves a 0.8-km. (0.5 mi.) wide corridor along the river. Wild Trout Stream status protects the river itself, but has no bearing on the surrounding lands other than requiring angling access. The FS is being actively encouraged to establish a special management area along the river, but this will probably only be a corridor and will only apply to public lands. Of all possibilities preliminarily studied, Research Natural Area (RNA) or Special Interest Area (SIA) designation seem to be the most desirable for appropriate public lands in the drainage.
In cases where timber values, public-use pressures, and/or priority ranking are low, it may prove best to take no action at all. Such areas are under what might be called de facto protection.
After prescribing preferred protection methods for each parcel of private land and evaluating protective land status designations for adjacent public lands, program options must be developed which unify these separate methods into overall strategy options. Development of a protection plan is in itself a unifying force, having one objective and involving one drainage, but when seeking public and government agency support, offering optional "package deals" will help ensure success of the plan. A similar approach was used in developing TNC's California Critical Areas Program; support for the individual critical areas would have been hard to come by without the unifying theme represented by the program. Each alternative package for the McCloud drainage will describe a desired ultimate land ownership pattern, zones of varying degrees of protected status with specific restrictions given (including applicable legal designations), and the costs and time frames necessary to accomplish each alternative. Within the theme of protection for the drainage, the alternatives will range from the "environmentalist's ideal" to the "limits of compromise", such that each one will be viable should it ultimately be the one supported by the public, governmental agencies, and TNC.
As an example, one alternative might be to recommend a university- or Conservancy-operated research field station along the river, surrounded by a RNA. The lower McCloud drainage is ideal for field studies involving fisheries biology, aquatic entomology, old growth forest-related wildlife biology, and studies of the endemic species and artifacts of the Baird Limestone Formation, to name a few. The existing upper portion of the Preserve would continue to be managed under the current public-use system, which could be located on the edge of the RNA and serve as a buffer.
Part of lower Squaw Valley Creek could be included in the RNA and added to the state's Wild Trout Stream system with the upper part being open to reduced-limit fishing as another buffer. Thus, the core of the RNA would be closed to fishing and adequately buffered to ensure undisturbed conditions for ecological protection and scientific study. Since the program would be closely tied with maintaining a high-quality angling stream, substantial financial support on a continuing basis could most likely be achieved from the angling public.
Once options have been developed, the draft protection plan will be circulated among appropriate agencies, clubs, and individuals to determine which alternative is most agreeable to everyone concerned. Once this is completed, TNC will have a fairly accurate idea of how to proceed with implementation of the protection plan.
During the implementation phase, the two most obvious needs will be financial and agency support. TNC has funds for acquisition, but in order to keep these funds available for the most critical of threatened areas, a local fund-raising campaign is initiated for every new project. The McCloud is fortunate in having the tremendous support of fly-fishing individuals and clubs across the western United States. Good trout streams are becoming quite rare, and at the same time the sport of fly-fishing is continuing to grow. A new consciousness has been developing along with the sport—an awareness of, and deep concern for, the ecological factors involved in a healthy stream and its surrounding environment. This is what has led to the success of the catch-and-release concept and the continued strong support of the existing Preserve.
Agency support will be much more difficult to achieve. Timber and water values rank very high in the drainage; Warner (1979) indicated that by the year 2000 35% more timber will be required and agricultural and urban uses of water will increase by more than 50%. The federal government is showing a declining interest in environmental concerns. Educational institutions must be convinced of the drainage's scientific value and of a dependable source of continued funding should a research field station be proposed. The "not invented here" attitude towards progressive and aggressive planning efforts could hinder progress with both other agencies and
fly-fishing clubs. The solution to this latter problem will be to include all concerned agencies, clubs, and individuals throughout the planning process, such that the protection plan is a product of cooperative effort, as it should be.
Other Planning Efforts
Beyond the in-house reasons for TNC's development of a McCloud River Protection Plan, such a plan is necessary to more effectively coordinate TNC involvement in the planning processes of other agencies in the drainage. To date, interactions with FS and DFG have been on a piecemeal basis, in response to specific threats. Both of these agencies are currently developing management plans affecting the McCloud River drainage.
Involvement in FS planning began in 1975 with the routing of the Pacific Crest Trail through the drainage. Subsequently, as specific timber sales in the drainage were planned, TNC has played an increasingly greater role in seeking minimal harvests, protective techniques, and thorough study of sensitive species and potential water quality impacts. Most recently, TNC has been involved in the development of the Shasta-Trinity National Forest Land and Resource Management Plan in which, it is hoped, a special management area will be established in the drainage and both timber harvest quotas and potential harvest-site suitability ratings will be more realistic. At present, the entire drainage is zoned for timber harvest. Two major drawbacks of this plan, with respect to the McCloud River drainage, are that it will address the whole Shasta-Trinity National Forest, of which the McCloud is only a small part, and it will only deal with public lands in the drainage.
Recent DFG involvement in the drainage began with Wild Trout Stream designation in late 1975, which included the establishment of a Dolly Varden Char Sanctuary within the Preserve. During 1977 and 1978, the river was surveyed from Lower Falls to Shasta Lake with the hope of finding Dolly Varden, and no confirmed sightings were made. It is suspected that the McCloud River population of Dolly Varden char may be genetically distinct, but the lack of sufficient sampling has prevented any progress on this subject, although the DFG is now referring to the population as the California bull trout. At this point the prospect for a rehabilitation project is uncertain, but protective management will nevertheless be encouraged. The most recent efforts to this end have been in the development of a lower McCloud River Wild Trout Area Management Plan. A preliminary position statement was released by DFG early in 1981 for consideration by the FS in their planning efforts.[14]
These other planning efforts indicate that TNC is in the best position to develop a protection plan for the drainage. However, it must rely upon the support of the users of the drainage (mainly anglers), because the range of values in the drainage extends beyond the strict limits of concern of TNC. To be successful, TNC must focus its limited resources upon the most critical of areas in the nation. With the goal of preserving biological diversity, TNC attempts to identify and protect those species and habitats which are the most threatened and scarce, or as they say, "the last of the least and the best of the rest."
Many of the McCloud's critical elements are represented elsewhere, such that their continued survival is not dependent solely upon this region. Exceptions to this are the possibly genetically distinct McCloud populations of Dolly Varden char and rainbow trout, and the Shasta salamander and eupatory. A very large part of the McCloud River Protection Plan will involve recreational/aesthetic values as well as habitats and species threatened to a lesser extent than those just mentioned. The plan will also address protection of the "essence" of the McCloud River drainage: the product of the river, forests, limestone, etc., which imparts a uniqueness to the region. For these reasons, the public will play a vital role in the development and support of the plan.
Conclusion
The ecological/scientific and recreational/aesthetic values of the McCloud River drainage possess enough significance and uniqueness to warrant their protection. The industrial values of the drainage are also significant and, until recently, have greatly outweighed other values. Multiple ownership, multiple agency involvement, and the preoccupation with industrial values have resulted in uncoordinated patterns of resource management and exploitation which are blind to the maintenance of ecological integrity of the system.
The McCloud River drainage is in need of long-term, system-wide, integrated planning. Local planning for national forests now occurs at the individual forest level; the McCloud River drainage is only a small part of the Shasta-Trinity National Forest and as such will probably not receive adequate attention in the soon-to-be-completed Land and Resource Management Plan for the forest. The FS is also not in a comfortable position to emphasize non-consumptive values in the drainage nor to deal with the various private ownerships. The DFG has become increasingly supportive of wild trout programs and would like to develop a plan for this program in the McCloud drainage; however, its approach would be focused on the fishery. TNC has come to recognize the need for appropriate planning in the drainage to both direct its future activities there and to attempt to integrate the activities of other
[14] Naylor, A.E. 1981. The lower McCloud River wild trout management area. Position Paper, California Department of Fish and Game, Region 1, Redding, Calif.
owners and agencies. As such, TNC seems to be the most likely candidate to develop a protection plan for the whole drainage, although it too, in the strict sense, has focused interests.
Recent evolution in TNC's planning efforts has led to the initiation of the McCloud River Protection Plan. By identifying critical elements, threats, ownership patterns, and alternative techniques for protecting land; by prescribing appropriate protection techniques to each geographical unit in the drainage, based upon ownership, critical elements, and threats; by developing viable alternative packaged protection programs ranging from the "environmentalists' ideal" to the "limits of compromise"; by securing public involvement and feedback throughout the planning process, with the goal of discovering the most widely acceptable protection program; and finally by implementing this program through the support of all owners, agencies, organizations, and individuals involved in the McCloud River drainage, TNC's hope is that the McCloud River Protection Plan will satisfy the need for a proper planning perspective here.
Work on the plan has only just begun. As with any environmental planning, it will involve finding a viable path of compromise through the jungle of conflicting interests in the drainage. But without some form of comprehensive planning, a piecemeal approach to protection will continue, jeopardizing the integrity of the magnificent system of the McCloud River.
Literature Cited
Seidelman, P. 1980. Methodology for evaluating cumulative watershed impacts. USDA Forest Service Region 5, San Francisco, Calif.
Sturgess, James A., and Peter B. Moyle. 1978. Biology of rainbow trout (Salmogairdneri ), brown trout (S . trutta ), and interior Dolly Varden (Salvelinusconfluentus ) in the McCloud River, California, in relation to management. Cal-Neva Wildlife 1978:239–250.
Warner, R.E. 1979. California riparian study program. 177 p. Planning Branch, California Department of Fish and Game, Sacramento.
Sacramento River Environment
A Management Plan[1]
Thomas J. Kraemer[2]
Abstract.—Riparian forest vegetation along the Sacramento River is necessary to control erosion and to promote deposition of sediments. Sedimentation is occurring at rates sufficient to replace some agricultural lands lost to erosion. Money spent on erosion control by riprap would be better spent acquiring a riparian corridor.
Introduction
In the last 20 years I have been increasingly dismayed by the degradation of the Sacramento River's environment in the upper Sacramento Valley. As a result I have spent the past three years studying the river and its riparian lands. This paper represents a portion of the study submitted as a Master's thesis[3] to California State University, Chico.
Erosion, Deposition, and Riparian Vegetation
The presence of significant amounts of riparian forest vegetation along the Sacramento River, to control erosion and to promote deposition of new sediments to replace those soils eroded by the river, is vital to any river system management plan. Riparian vegetation is intimately involved in the sedimentation process. It provides a baffle effect which acts to slow high winter flows enough to allow the deposition of suspended sediments. Furthermore, surface erosion is usually prevented and bank erosion inhibited by the presence of riparian forests. These processes are illustrated in figure 1. The two areas depicted in figure 1 are protected by the same riprap. Note that the river bank has been "stabilized" by the installation of rock riprap, but that the land it was designed to protect has been eroded. The field has eroded and the area of uncleared riparian vegetation has remained stable and, in fact, has caused sediment deposition.
Sedimentation and replacement of eroded soils is thought by some not to be occurring in significant amounts along the Sacramento River since construction of Shasta Dam near Redding. However, significant sedimentation and soil replacement are indeed occurring. Using aerial photos, I have found areas which were shown to be river channel on 1952 maps, and which were subsequently reclassified as prime agricultural land in 1978 by the State of California, Department of Water Resources in the Sacramento River Environmental Atlas (California Resources Agency 1978).
Erosion along the Sacramento River has caused a great deal of damage to agricultural lands. Erosion of agricultural land adjacent to the river is accelerated by forest clearing. Paradoxically, forest clearing and cultivation agriculture immediately adjacent to the river are the causes of accelerated erosion rates at some sites and of related reduction of riverbed sinuosity which has occurred in the last 100 years (Brice 1977). Attempts to control erosion with bank stabilization projects (commonly called riprap) have met with limited success, and are unsuccessful in many instances.
Erosion Control Projects
In 1958–1959 the Federal Government and the State of California authorized the Chico Landing to Red Bluff Project.[4] The Project subsequently spent millions of dollars installing riprap on eroding banks, in an effort to stabilize them.[5] Because of the losses of riparian forest habitat and continuing expenditures by the taxpayers for flood damage, the State of California has withdrawn its support for the Chico Landing to Red Bluff Project, while further
[1] Paper presented at the California Riparian Systems Conference. [University of California, Davis, September 17–19, 1981].
[2] Thomas J. Kraemer is a Conservation Ecologist located in Corning, Calif.
[3] Master's thesis "The Sacramento River, Glenn, Butte, and Tehama Counties: a study of vegetation, deposition, and erosion, and a management plan." California State University, Chico. Spring, 1981.
[4] US Army Corps of Engineers, Sacramento District, Sacramento, California. Supplement no. 2 to general design memorandum no. 1, Sacramento River, Chico Landing to Red Bluff, California. June 18, 1976. p. 1.
[5] Ibid. Item 25.
Figure l.
River Mile 220.2, right bank. May 1978. The photo on the left shows uncleared riparian vegetation on the left, and land cleared of
riparian vegetation and farmed on the right. The river is to the viewer's back. The photo on the right was taken at approximately
the same position as the one on the left, only turned 90° so that the river and formerly farmed lands are visible.
studies are made of alternate approaches.[6] State involvement is necessary for Federal participation in bank protection and, due to this, recent installations of bank protection have been limited to sites where work had been initiated and funded prior to the State's decision.[7] Fiscal year 1978 was the last year the State Reclamation Board recommended State cooperation in the Chico Landing to Red Bluff Project although the Federal agency involved, the US Army Corps of Engineers (CE), continues to study erosion and erosion sites along the Sacramento River.[8]
In 1958 the CE was authorized by Congress
. . . to provide bank protection and incidental channel improvements between Chico Landing and Red Bluff in Butte, Glenn and Tehama counties at certain sites found to be economically feasible at the time of construction and in the light of conditions then prevailing along the river . . .[9]
A 50 year amortization, or economic life, was used when computing the costs and benefits of selected sites.[10]
Average annual benefits . . . were based on a reduction in the loss of land and improvements which would be prevented at each site by the construction of bank protection . . . In addition annual benefits were based on a reduction in downstream dredging in the channels and bypasses of the Sacramento River Flood Control project, Sacramento River Deep Water Channel, and San Francisco Bay System Channels.[11]
One of the erosion sites protected in the Chico Landing to Red Bluff Project is located at River Mile (RM) 196.3, near the mouth of Pine Creek, Butte County. Aerial photos dated 1952
[6] James Dufur. "300 mile parkway on big river is dream." Sacramento Bee. April 3, 1979. Sec B p. 1.
[7] US Army Corps of Engineers, Sacramento District, Sacramento, California. Supplement no. 2 to general design memorandum no. 1, Sacramento River, Chico Landing to Red Bluff, California. June 18. 1976. Item 3.
[8] Gene Anderson. 1981. California State Reclamation Board. Telephone interview.
[9] Sacramento River, Chico Landing to Red Bluff, California. Bank protection project. Final environmental statement. Prepared by US Army Corps of Engineers, Sacramento District, Sacramento, California. January 1975. p. 1.
[10] Ibid . p. 4.
[11] US Army Corps of Engineers, Sacramento District, Sacramento, California. Supplement no. 2 to general design memorandum no. 1, Sacramento River, Chico Landing to Red Bluff, California. June 18, 1976. Item 21.
and 1975 were used to analyze this site. The 1975 photos were chosen because they accurately record the position of the riverbank, minus materials removed during the 1974 construction of bank protection.[12] Site evaluation was undertaken by overlaying a grid on the photos, to determine areal changes during the 22-year period in question. No areal change could be detected; that is, the amount of dry land within the measured area remained the same over the 20-year period. Reference was then made to the USGS 7.5 min. series quadrangles, 1949 edition and 1969 revision.[13] Almost no change in bank position was recorded. Comparison of the 1952 and 1970 aerial photos disclosed that some of the oak trees visible at this site in 1952 were missing in 1970. This was interpreted as evidence of erosion. Finally, on closer examination, and using an engineer's scale referred to a fixed point, measurements indicated that the bank had eroded 25 ft.
Examination of the 1979 aerial photo for this site and comparison with the 1975 aerial photo revealed a change in river channel between 1975 and 1979. During this period a cut-off occurred upstream from the riprap site. By 1980 the entire flow of the river had been diverted into the new cut-off channel and the old channel was completely blocked by alluvium. This change left the bank protection site in a backwater, useless, as it was isolated from the river.
Bank Protection Costs and Benefits
Construction at the RM 196.3 site was completed in 1974 at an approximate construction cost of $115,000.[14] An additional cost factor of 20% for engineering, design, and administration costs should be added to this to arriye at a total Federal first cost of $138,000.[15] At this particular site State costs are ignored because the land in question was donated.[16]
Prior to the installation of bank protection at this site, the underlying erosion-resistant layer of clay material at and above the water line was visible.[17] This layer would account for the lack of significant bank movement observed in the aerial photographs between 1952 and 1975.
A 1975 CE document lists a projected cost: benefit ratio for this site of 1.1.[18] The same document uses a 50-year economic life when computing the costs and benefits of a site. However, at this site the river changed course after five years, with no further river flow past this bank protection site. Thus, after but six years of an anticipated 50-year project life, no further benefit was being gained from reduced damages due to potentially eroded land and washedout structures. Nor will there be a further reduction of dredging costs in the delta for sediments which would have originated at this site in the absence of bank protection. At this site the benefits have ceased after six years but the costs will continue for another 45 years.
This bank protection failure is not an isolated case. I selected 14 riprapped sites for study, five of which were examined in detail. These sites were located between RM 220.5 (near the mouth of Deer Creek, Tehema County) and RM 196.3 (near the mouth of Pine Creek, Butte County). Six of the 14 bank protection sites reviewed have failed completely or are in advanced stages of failure. All six are less than 10 years old. In addition four more sites have potentially serious problems which could lead to a resumption of serious erosion at those sites.
Structural Bank Protection Versus the River
The Sacramento River is a dynamic entity, eroding here, depositing there. It is the river's hydrologic nature to form meanders and cut-offs. Indeed, if it were entirely straightened, the river would immediately begin to reform a meandering system (Strahler and Strahler 1978). The management system (rock bank protection) applied for the purpose of controlling river channel movement has been haphazard and expensive, requiring constant maintenance to retain the effectiveness of each site. In an interview with an official of the US Army Corps of Engineers, Sacramento, it was learned that the ultimate goal of that agency is to "freeze" the river in place.[19] In his opinion, this could be done, if economically feasible, by riprapping the outside of every bend in erosion-prone areas. This would necessitate a very large initial expenditure and also require continual maintenance of the channelized system thereafter. In
[12] Sacramento River, Chico Landing to Red Bluff, California. Bank protection project. Final environmental statement. Prepared by US Army Corps of Engineers, Sacramento District, Sacramento, Caifornia. January 1975. p. 14, 19.
[13] USDI Geological Survey. Ord Ferry Quadrangle California, 7.5 Minute Series (Topographic) 1949 and Photo Revised Edition 1969.
[14] Construction data, various bank protection sites, Sacramento River, California. Document received from US Army Corps of Engineers, Sacramento District. February 15, 1980.
[15] Don Jones, US Army Corps of Engineers, Sacramento, California. Telephone conversation. April 15, 1980.
[16] Jake Angel, Department of Water Resources, Sacramento, California. Telephone conversation. March 12, 1980.
[17] Field observation. June 1969.
[18] Sacramento River, Chico Landing to Red Bluff, California. Bank protection project. Final environmental statement. Prepared by US Army Corps of Engineers, Sacramento District, Sacramento, California. January 1975. p. 5.
[19] Interview with Dave Gundlach, US Army Corps of Engineers, Sacramento office. March 27, 1980.
addition, if this system were implemented, nearly all remaining riparian growth would be eliminated. The loss of this forest and grassland would reduce and probably eliminate the soil formation processes that lead to the prime (high terrace) agricultural land so highly prized by farmers. Erosion would not cease. Overbank erosion would still occur, as would scour at the downstream ends of bank protection sites. Figure 2 illustrates one such scour site. Most wildlife and recreation values would be eliminated. With banks riprapped and the loss of the forest, little would be left of wildland and aesthetic values. This would be very costly indeed.
An Alternative Strategy
Acquisition of a Riparian Corridor
A less costly alternative is available. Instead of installing riprap and channelizing most of the Sacramento River, the money which would be spent on such projects could be spent to acquire land, the land which is eroding, if possible.[20]
Figure 2.
River Mile 206.5, left bank looking downstream.
August 1979. Scour damage at downstream end of
riprap installation. The soil has been eroded from
behind the riprap for about 30.5 m. (100 ft.)
Farmers would be forewarned that no money would be spent to protect agricultural sites from erosion, but if they should desire to sell the land in question, it would be purchased with public funds. Only those sites where extensive urbanization has occurred and where public structures, such as bridges, have been built would be structurally protected.[21] If the individuals involved chose not to sell their land, other land would be acquired. In this way, over an extended period of time, a corridor of public land adjacent to and on both banks of the river would be acquired.
If a corridor were acquired, erosion would not cut away the land to one man's detriment, only to deposit it further downstream on another's, to that person's benefit. If the meander zone of the river were encompassed by a corridor of public land, there would be only one landowner, the public. The public would not be harmed by erosion here or benefited by deposition there. No single landowner would be hurt by erosion. Landowners would not bring suit against governmental agencies for flood damages, as is presently the case. Riprap would be unnecessary in most instances.
The acquisition of a corridor does not have to be finished tomorrow or even next year, or even in the next 20 years. Only a stated policy by the Federal and/or State government(s) and funding are required. If the corridor is finished in a century it is time enough. Land would not need to be condemned. If the public is willing to wait long enough, all the land in the meander zone will sooner or later be offered for sale.
The money spent on riprap installation and maintenance would be better spent on land acquisition. Many riprap sites have failed or are failing. The money already spent on these particular sites would have been far better spent on the purchase of land. If it had been, the public would now have a resource, instead of a rock pile, sometimes remote from the river.
Cost Comparisons
At RM 211, simple calculations reveal that if the rate of erosion for that site during the 20-year period analyzed were projected for the 50-year economic life of the installation, approximately 23 acres will have been lost. Total first cost at that site was $348,000 in 1976.[22] In 1976 orchard land cost about $3,000
[20] Indeed, the USDA has suggested that an effort be made to obtain a strip of property adjacent to the river so that riparian vegetation can be reestablished. Sacramento River, Chico Landing to Red Bluff, California. Bank protection project. Final environmental statement. Prepared by US Army Corps of Engineers, Sacramento District, Sacramento, California. January 1975. Appendix C-4.
In addition the Resources Agency, State of California, has proposed a parkway of public easements along the entire length of the Sacramento River. James Dufur, "300 mile parkway on big river is dream." Sacramento Bee. March 4, 1979. sec. B. p. 1.
[21] It is unlikely that existing bridges would be outflanked by a freely meandering river. In the long term, when such bridges are replaced consideration should be given to a bridge and/or causeway system, such as those at Butte City and Sacramento.
[22] Amortized costs are not included because land purchase also has such costs.
per acre. If the money had been spent on land purchase instead, 116 acres could have been bought.
Corridor Width
The ultimate width of such a riparian corridor, at least in the absence of a public levee system, as is the case north of Ord Ferry Bridge at RM 184.3, should be the width of the recent alluvial soils, or the width of the levee system maintained by public funds. If there is a danger of the river outflanking the existing levee system at its northern terminus, i.e. the river changing course to the outside of the levee, lateral levees could be built across the floodplain, at right angles to the existing levees which are parallel to the river.
Along that portion of the river without a public levee system, particularly north of Ord Ferry Bridge, the corridor ideally should have two management zones. There would be one zone adjacent to the river itself including, initially, all standing riparian forest and a band of perhaps a minimum of 183 m. (200 yd.) wide. This band would be left to revegetate naturally or would be planted to oaks, black walnuts, and whatever riparian species suited the site.[23] The second zone would include the balance of the corridor. In this second zone, agriculture would be practiced on a leasehold basis. The terms of the lease would be such that, if the river did meander or flood into the agricultural zone, the farmer in queston would not be able to make a claim for the financial loss. Flooding and erosion would simply be hazards that the farmer accepted when the lease was signed, as is now the case in the several river bypasses.
Given the development of a meander situation and its attendant erosion of agricultural land, the lease, once expired, would not be renewed. Then the boundaries of the two zones would be redrawn. In like a manner, once lands become suitable for agriculture and, due to river meandering, are found outside the inner riparian zone, they would be leased for agriculture, and forest clearing allowed. In this way a balance between the values of the river environment and the productive usefulness of these soils would be struck.
There is no question that the agricultural potential of the river's alluvial soils is immense. These soils should where possible be used for agriculture. But there are other values to be considered—wildlife, recreation, aesthetic, and, most important to those who consider economics, the cost of efforts to shore up the river's banks. This plan allows for both the needs of agriculture and the retention of wildland along the river. It also guarantees a minimum of expense to the public and the farmer.
Land Revenues and Maintenance Costs
Many will be concerned about the loss of tax revenues to local government implied in such a plan, but such revenue losses need not occur. Lease monies collected by governmental agencies administering the agricultural zone should be shared with local government. Indeed, the precedent for this already exists. When timber is sold from public lands within the National Forests, the USDA Forest Service is obliged to share the revenues from those sales with the county government where the timber originated.
The public ownership plan, if implemented, would offer many advantages over the channelizing option. The river would be allowed to meander naturally, at least where no publicly maintained levee system exists. The necessity for bank protection would be eliminated, except in those areas where there are structures such as bridges, or where pre-existing urbanization is established, such as the towns of Tehama and Red Bluff. However no further urbanization would be allowed on the floodplain. Farming would be allowed in such a way that production could be maximized. Natural soil building processes would proceed at a maximum rate because of the presence of riparian vegetation, thus replacing soils lost to erosion. Wildlife and wildland values would be conserved and enhanced.
The initial investment for such a plan would be high, but for the channelization option costs are presently high, as are those for maintenance, with no guarantee that the amortized life will be actually achieved. With either option, administration costs will be incurred. However, with the riparian corridor plan, initial outlays are high, but an income-producing resource remains, and a minimum of maintenance is required. Conversely, with the channelization option, money input will be required for installation, maintenance, and reinstallation, so long as the river is to be kept channelized. Benefits are terminal, costs are forever. It is a matter of good economics: with the riparian corridor plan, costs are terminal, benefits are forever.
Literature Cited
Brice, James. 1977. Lateral Migration of the Middle Sacramento River, California. Water Resources Investigations 77-43 (July 1977). USDI Geological Survey.
California Resources Agency. 1978. Sacramento River Environmental Atlas. Prepared for the Upper Sacramento River Task Force by the California Resources Agency. Sacramento.
Strahler, Arthur N., and Alan H. Strahler. 1978. Modern Physical Geography. John Wiley and Sons Inc. New York.
[23] The proposed dimensions are subject to adjustment, as the needs of the corridor require.
Riparian Area Management in the Pacific Southwest Region of the Forest Service[1]
Andrew A. Leven[2]
Abstract.—This paper presents the history and evolution of riparian area management direction for National Forest System lands in California since the early 1960s. Application of national riparian area management direction to Regional and National Forest planning processes along with examples of project plans for improvement and maintenance of riparian areas are presented. Some research needs for management activities to improve and maintain the health of riparian areas are discussed.
History of Regional Direction
The USDA Forest Service (FS) has long had a means of recognizing unique management requirements of riparian areas. Since the early 1960s, "water influence zones" have been used in multiple-use plans to designate streams of high recreational value. This value generally was dependent on fishing, scenic, and water sports-related recreational uses. These water influence zones received management direction aimed at protecting their recreational values. Targets for forest commodities were established through multiple-use and resource plans. Many of these targets are still in effect today.
In addition to national water influence zone management direction, in 1966 the FS in California developed a procedure to evaluate a stream channel's ability to accept the impacts from uses such as timber harvesting without the need for special management direction. The process classified streams as "resistant" or "non-resistant." Classification criteria were based mainly on streambank and streambed condition. If streams were resistant to erosional processes accelerated by mechanical disturbance, they were classified as resistant. If erosion would be accelerated by disturbance, the streams were classified as non-resistant. Special clauses were placed in timber sale contracts which called for limited and/or restricted actions in non-resistant streams. The main purpose of these clauses was to protect streams from accelerated erosion caused by direct mechanical disturbance. The criteria were related to physical stream conditions, but the management direction was not closely tied to stream values.
The need remained for specific management direction that was more closely tied to stream values, and conditions. In 1975 the Pacific Southwest Region of the FS developed direction that required the extent of stream protection be tied to stream values. The stream value classification system is still in use today and is based upon an evaluation of the following minimum factors: 1) flow characteristics; 2) present and foreseeable instream and downstream values associated with waters of the stream; and 3) physical and biological characteristics of the stream environment.
Each class establishes the relative importance or significance of a stream or stream segment, based on resource values and beneficial uses. This system is only a step toward the ultimate objective, i.e., a detailed description of the final protection measures needed. The following is a description of each class as taken from a Regional Supplement to the National Forest Service Manual:
Class I, Highly Significant. These are either perennial or intermittent streams, or segments thereof, which meet one or more of the following criteria:
a. Are habitat for large numbers of resident and/or migratory fish for spawning, rearing, or migration.
b. Furnish water locally for domestic or municipal supplies.
c. Have flows large enough to materially influence downstream water quality.
d. Are characterized by major fishing or other water-oriented recreational uses.
[1] Paper presented at the California Riparian Systems Conference. [University of California, Davis, September 17–19, 1981].
[2] Andrew A. Leven is Director, Watershed Management Staff, Pacific Southwest Region, USDA Forest Service, San Francisco, Calif.
e. Have special classification or designation, such as wild, scenic, or recreation rivers.
f. Have special visual or distinctive landscape features and are classified as variety class A as defined in "National Forest Landscape Management Volume 2" (Agr. Handbook 462).
g. Are habitat for threatened or endangered animal species, or contain plants which are potential or viable candidates for threatened or endangered classification.
h. Exhibit ethnological, historical, or archeological evidence that makes them eligible for or are included in the National Register of Historical Places.
Class II, Significant. These are either perennial or intermittent streams, or segments thereof, which meet one or more of the following criteria:
a. Are used by moderate numbers of fish for spawning, rearing, or migration.
b. Furnish water locally for industrial or agricultural use.
c. Have enough water flow to exert a moderate influence on downstream quality.
d. Are used moderately for fishing and other recreation purposes.
e. Are of moderate visual quality and meet variety class B as defined in "National Forest Landscape Management Volume 2" (Agr. Handbook 462).
Class III, Moderately Significant. These include perennial or intermittent streams, or segments thereof, which meet one or more of the following criteria:
a. Are habitat for few fish for spawning, rearing, or migration.
b. Are rarely used for fishing or other recreational purposes.
c. Have enough water flow to exert minimum influence on downstream water quality.
d. Are of relatively low visual quality in the landscape and classified as variety class B as defined in "National Forest Landscape Management Volume 2" (Agr. Handbook 462).
Class IV, Minor Significance. These are intermittent or ephemeral streams, or segments thereof, not previously classified (Forest Service 1975).
Land management planning use of the system requires those streams, or segments thereof, which meet the criteria for Class I and II to be shown on land management planning maps; Class III and IV streams may be shown as appropriate. Within project areas all streams and segments must be classified. Management direction and protection measures for the stream zone are then developed for the specific planning unit or project area. This direction is aimed at measures which ensure favorable conditions of water flows and protect the natural environment commonly associated with streamcourses.
The use of buffer strips, areas adjacent to the stream channel, came into use in the early to mid-1970s, to provide protection beyond protecting just the channel. The use of buffer strips was recognized as providing more effective protection to streams and streamside areas during land management activities, by reducing site disturbance and filtering sediment from adjacent upland areas. Buffer strips of a width sufficient to provide such protection are designated during all land management activities which involve land use in close proximity to streams. Resource management activities are permitted within the buffer strips, but are modified so as to safeguard the stream and its natural environment from adverse impacts resulting from such activities.
Some general guidelines for management activities within buffer strips were provided in Regional Forest Service Manual Supplements in 1975 (USDA Forest Service 1976). Several are summarized below.
1. Riparian systems are among the most productive of plant and wildlife diversity in the forest environment. To retain these valuable areas, minimum disturbance from management activities is essential.
2. The shade canopy produced by riparian vegetation overhanging the water surface will be retained in streams where maintenance of proper water temperature is essential for perpetuation of aquatic life. Within timber sales areas, if there are not sufficient hardwoods along the stream to provide this shade, canopy conifers must retained as needed.
3. Adequate protection to the buffer strip must include protection of the soil, litter, and vegetative cover, as well as the streamcourse itself. This may require adjustments in normal operating procedures including appropriate modifications of road locations, silvicultural prescriptions, and uses of heavy equipment.
4. Trees may be removed from the buffer strip if their removal will not adversely affect the watercourse or the buffer strip. Trees to be removed must be individually marked.
5. Heavy equipment and roads, roadfills, and sidecasting must be kept outside of the buffer strip, except at designated crossings and for specifically planned and authorized activities.
Forest Supervisors were given authority to provide management guidelines for streamcourse protection appropriate to their administrative units and to prescribe the method to determine the buffer strip width needed to provide stream protection commensurate with planned land management activities.
In 1975, wildlife and fishery biologists in the Pacific Southwest Regional Office identified a number of goals, objectives, and management activities related to protecting riparian systems.
Goal: To gain recognition and acceptance of the importance of riparian systems to wildlife needs and to implement coordination measures which provide for these needs in land-use planning and resource management activities in national forests.
Objective: To preserve the productivity of riparian systems by maintaining vegetative stratification and integrity. This will result in maintaining wildlife diversity and a stable ecosystem.
Examples of how riparian system management is coordinated with other forest resource management programs are listed below.
1. Recognize riparian systems in timber management planning by establishing protective areas along streams. Coordinate timber harvest activities to avoid damage to riparian systems.
2. Locate campgrounds, access roads, and trails outside of riparian zones.
3. Manage domestic livestock to avoid trampling and overgrazing vegetation in riparian zones.
4. Allow adequate buffer zones when using chemicals to control vegetation near riparian systems.
5. Carefully consider wildlife needs when planning projects to increase water yield through removal of vegetation in the riparian zone.
6. Protect small springs and seeps from trampling and other damaging impacts by fencing the area.
During 1978 and 1979, while participating in Section 208[3] nonpoint pollution abatement water quality planning, the Pacific Southwest Region consolidated its water quality direction into a document describing best management practices (BMPs) for protecting water quality (Pacific Southwest Region, USDA Forest Service 1979). Some of these BMPs included direction for riparian area management because of its relationship to water quality. Twenty different BMPs were described that have some relationship to management of riparian areas for protecting water quality. A few of the subjects and activities addressed were: streamside management zone designation; meadow protection during timber harvesting; minimization of sidecast material; control of in-channel excavation; construction in streamside management zones; exclusion of tractors from wetlands and meadows; control of livestock distribution within allotments.
It is important to note that these BMPs were consolidated from existing manual direction and were not newly developed during or as a result of Section 208 planning. These practices were approved by the US Environmental Protection Agency (EPA) and adopted by the State of California as BMPs for protecting water quality on National Forest System lands. It is also important to note that this was the first introduction of the streamside management zone (SMZ) into a formal FS direction document. Up to that point, direction had related to stream protection. The SMZ introduces the concept that streams must be managed and that protection is only one form of managament.
History of National Direction
In 1976–77, the concern for managing riparian areas to maintain their ability to protect water quality and provide diverse fish and wildlife habitats began to reach national and political levels. The Chief of the FS commissioned a team to review SMZ management on a national scale. This review identified the need for a uniform definition of the SMZ and for criteria to guide overall management of SMZs. These needs were based on review team findings indicating a wide divergence among FS regions in the identification of permitted management activities within SMZs. In general, riparian areas were recognized for their importance in maintaining water quality and wildlife/fisheries habitat; however, there were numerous examples of conflicting uses of these areas. Examples of these uses include: livestock grazing, timber harvest, recreation campsites, and floodplain development.
The Chief's staff began working on national guidance to provide uniform definition of SMZs and policies for their management. While the work was proceeding, Executive Order 11988—Floodplain Management and Executive Order 11990—Protection of Wetlands were signed by President Carter on May 24, 1977. The National Forest Management Act[4] was passed October 22, 1976, providing guidance to the formulation of national Forest Service policy. Several interim directives were written and rewritten to include the Presidential and Congressional direction. Even though work began nationally in 1976, these rewrites delayed finalization of national direction until 1980. (This paper will not discuss the intent of this Presidential and Congressional directive.)
The following national FS policy was published in April 1980:
The Forest Service shall manage riparian areas in relation to various legally mandated requirements, including, but not limited to those associated with floodplains, wetlands, water quality, dredged and fill material, endangered species, wild and scenic rivers, and cultural resources.
Riparian areas must be managed in the context of the environment in which they are located. Specifically, the policy of the Forest Service is to:
[3] PL 92–500, Federal Water Pollution and Control Act, as amended. 33 U.S.C. 466.
[416] U.S.C. 1600.
1. Recognize the importance and distinctive values of riparian areas during the land management planning process.
2. Recognize the importance and distinctive value of riparian areas when implementing management activities. Give preferential consideration to riparian area-dependent resources over other resources in cases of unresolvable conflict.
3. Manage riparian areas under the principles of multiple use and sustained yield, while emphasizing protection of soil, water, vegetation, and fish and wildlife resources.
4. Delineate and evaluate riparian areas prior to implementing any project activity (USDA Forest Service 1980).
The 1980 policy and direction also provided the standard agency definition of riparian areas as:
Geographically delineated areas, with distinctive resource values and characteristics, that are comprised of the aquatic and riparian ecosystems, floodplains, and wetlands. They include all areas within a horizontal distance of 100 feet from the edge of perennial streams or other water bodies (ibid .).
The last sentence shows the influence of including National Forest Management Act direction into the definition of riparian areas.
One of the more significant parts of the current national direction deals with a discussion of management activities in riparian areas.
It is important to recognize that timber harvesting, grazing, recreation, wildlife uses, and road construction are examples of activities that are compatible with and may occur within riparian areas. Some resources, however, such as fish, certain wildlife and vegetation, and water are totally dependent upon riparian areas. Other resources, such as timber, forage, minerals, visual and cultural activities, such as transportation and recreation, are not always dependent upon riparian areas.
Actions within or affecting riparian areas will include protection and, where applicable, improvement of dependent resources. Other resource uses and activities will occur to the extent they support or do not adversely affect the maintenance of riparian area-dependent resources. Preferential consideration is given to riparian area-dependent resources over other resources and activities when conflicts occur (ibid .).
In July of 1981, FS national policy and direction was published for the management of floodplains and wetlands, to implement the intent of executive orders 11988 and 11990. The national policy includes the following:
a. Provide opportunity for early public review of plans or proposals for action in floodplains, or for new construction in wetlands . . . including Federal actions for which the impact is not significant enough to require the preparation of an environmental impact statement . . .
b. Apply sound floodplain and wetland management to all agency activities, including long-range planning, program reviews, and individual project actions on National Forest System lands, and State and private forestry assistance programs.
c. Avoid, to the extent possible, long- and short-term adverse impacts which may be associated with the occupancy and modification of floodplains and with the destruction, loss, or degradation of wetlands.
d. Avoid direct and indirect support of floodplain development and new construction in wetlands wherever there is a practicable alternative.
e. Reduce the risk of flood loss to minimize the impacts of floods on human health, safety and welfare.
f. Promote the use of nonstructural flood protection methods to reduce the risk of flood hazard and flood loss.
g. Capitalize on opportunities to restore and preserve the natural and beneficial values served by floodplains, and to preserve, enhance and manage the natural and beneficial values of wetlands.
h. Adhere to the objectives of the Unified National Program for Floodplain Management published by the United States Water Resources Council, and provide leadership in applying the conceptual framework and strategies set forth by the Council to Forest Service programs.
i. Promote sound floodplain management, and protection and management of wetlands on non-Federal forest and range lands (USDA Forest Service 1981a).
This national direction also requires the use of the Water Resource Council's eight-step decision-making process for applying for the floodplain executive order (ibid .). The eight steps are given below.
Step 1. Determine whether the proposed action is located in the 100-year floodplain (500-year floodplain for critical actions), or whether it has the potential to affect a floodplain or indirectly support floodplain development. If not, or if an action is of an emergency nature, requirements of the executive order will have been satisfied.
Step 2. Notify the public at the earliest possible time of any plan or proposal to undertake, support, or allow an action which would result in the occupancy, modification, or development in a floodplain, and involve the affected and interested public in the decision-making process.
Step 3. Identify and evaluate practicable alternatives to locating a proposed action in a floodplain, including alternative sites outside the floodplain, alternative actions serving the same purpose as the proposed action, and the "no action" option.
Step 4. Identify the full range of potential direct or indirect adverse impacts associated with the occupancy or modification of floodplain and the potential direct and indirect support of floodplain development that could result from the proposed action.
Step 5. Identify and evaluate mitigation measures that will minimize the potential adverse impacts of the action if avoidance cannot be achieved, and measures that will preserve and restore or enhance the natural and beneficial floodplain values that would be adversely affected by the action.
Step 6. Reevaluate the proposed action. First, determine if it is still practical, even with the application of appropriate mitigating measures, in light of its exposure to flood hazards, and its potential to adversely affect the floodplain. Then determine if the alternatives identified in step 3 are practicable in light of information gained in steps 4 and 5.
Step 7. Prepare and provide the public with a finding and public explanation of any final decision when there is no practicable alternative to locating an action in or adversely affecting a floodplain.
Step 8. Provide ongoing review of implementation and post-implementation phases of the proposed action to ensure that all provisions associated with the action, including appropriate mitigating measures as identified in the environmental assessment, are fully implemented.
The preceding discussion is a synoptic history of the evolution of riparian area management philosophy which has resulted in the current national and regional agency direction to manage riparian areas in the FS. Some examples of how this direction is being applied on National Forest System lands in California follow.
Regional Planning
In October 1980, the Pacific Southwest Region began regional planning to implement the National Forest Management Act. Replies to a solicitation for regional issues and concerns indicated a public concern over the intensity of management activities occurring in riparian areas. The concern was also expressed that upland land-use activities were taking place at a rate that could result in a damaging cumulative effect on downstream riparian areas. National Forest managers expressed a concern that historic and current land uses on inholdings could be preempting land-use options on National Forest System lands.
To address these public issues and FS concerns, the personnel in national forests were directed to analyze the individual and cumulative effects on riparian and other sensitive areas of producing forest products. National forests could then compare commodity production assigned under multiple-use plans with production under current riparian management direction.
The regional plan is a vehicle for passing national resource production targets for forest commodities assigned to the region down to the individual national forests. The personnel of the individual forests then determine their capability to produce these assigned commodities by developing a forest land and resource management plan. Forest production capacity is aggregated into a regional capability which in turn is aggregated into a national capability. The national capability is used in developing an updated ES program under the Resource Planning Act (RPA)[5] . This is the first real opportunity that personnel of the individual forests, using site-specific information, have had to adjust national targets that may affect riparian area management.
Forest Planning
National forests are scheduled to complete their first forest land and resource management plans by 1983. Draft environmental impact statements and draft forest plans are presently being or will shortly be circulated for public review by the Klamath, Shasta-Trinity, Sierra, and Six Rivers national forests.
Since these are draft documents, and an alternative has not been finalized, it is too early to tell what management changes may result from the riparian area direction that has been established since 1978 (the time at which concern was recognized at the national level). Interested individuals should make a point to review forest planning documents and offer their comments.
Project Planning
There are two general types of project plans—plans for improvement and plans for maintenance.
Riparian Area Improvement Plans
Riparian area improvement plans are developed to improve existing conditions in riparian areas. A few of the activities commonly undertaken include structural treatments in stream channels to improve fish-rearing habitat and
[5] Forest and Rangeland Renewable Resource Planning Act of 1974, as amended. 16 U.S.C. 1600–1614.
stabilize streambanks to reduce sediment; planting vegetation for shade and soil surface cover; relocating stream crossings, campgrounds, and structures; and fencing to control livestock use.
The following is an extract from Section VIII (Treatment) of "Prescription and Environmental Analysis, Trail Creek" (USDA Forest Service, Inyo National Forest 1979). It is given here as an example of a riparian area improvement plan.
1. Place approximately thirty stream gabions in Trail Creek to slow water velocity and retain moving materials. Gabions are to be made of local rock, with wire and posts as needed. The middle portion of the gabion is to rise 6–10 in. above the original water surface. On approximately seven of these, the streambank is to be reinforced with rock to provide stabilized cattle crossings immediately above the gabions.
2. Evaluate the feasibility of placing approximately three to five stream gabions of "porta-plank" or other interlocking sheet metal in the deep, narrow sections of the stream unsuitable for rock gabions. Proceed if feasible—1979 or 1980.
3. Reroute the present road around three wet meadows that are presently receiving damage. Clear brush on the new roadway. Place enough small boulders on the entrance and exit of the abandoned roadways to discourage further vehicle travel.
4. Rock the road in one wet meadow where it is not possible to reroute. Haul rock locally.
5. Fence the spring located south of Trail Creek in "Camp Meadow." This spring had been fenced at one time but is now being trampled by cattle. Plant aspen shoots inside the approximately 40-foot square enclosure in wet parts. Aspens provide valuable wildlife habitat and are rare in the canyon.
6. Fill the old pipeline trench in Camp Meadow to help raise the water table. Fill in the sump hole on the south side of the creek at the campsite directly below the pond to help raise the water table.
7. Wet area protection—fence the swampy spring area above the pond to exclude cattle from approximately one acre. Plant aspen.
8. Continue the present system of rest-rotation grazing as prescribed in the Trail Canyon Cattle Allotment Management Plan.
9. Continue the program of winter burning in Trail Canyon as proposed in the Trail Canyon EAR for prescribed burning. Thirty-six acres have been burned since 1975. Burning is to be coordinated by the Wildlife Biologist and Resource Officer.
a) Burn a total of 163 acres of mixed woody and meadow vegetation at regular intervals as follows:
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Meadow will be increased from 42 to 93 acres by burning former meadow areas being overtaken by woody species. These areas still should have some type of grass understory to be suitable for burning as meadow.
Burn woody areas lacking understory once every 15 years. When convenient, burn invading wildrose patches more often.
Leave 65 acres of woody species along the creek unburned, including the apsen patch below the pond, and local stands of mature woody vegetation immediately adjacent to campspots. (Campspots can be easily identified by the presence of rock campfire rings and adjacent parking spots.)
b) Burn in late fall, winter or early spring to protect nesting or denning wildlife and perennial forage plants. The cost of burning is estimated to be $35 per acre. Fuels management would conduct the actual burning in coordination with wildlife and range management.
10. Apply 2,4-D to sprouting wildrose, willow and rabbitbrush the following growing season after prescribed burning. Spray only to restore areas with grass understory back to meadow habitat. Leave other areas to be used as young browse forage for wildlife and livestock. Complete the necessary application and permits prior to herbicide application and follow established guidelines necessary for safe application. In this case, do not spray within 10 feet of the stream if by hand; or 20 feet if by ground rig. This area should not be sprayed aerially. Spray only with wind less than 5 mph. A supplementary EA [environmental assessment] for herbicide application may be necessary in addition to this document.
In fiscal year 1980, approximately $1,732,000 was obligated to conduct watershed and fishery habitat improvement. These treatments were primarily in riparian areas. In fiscal years 1981 and 1982, it is estimated that national forests in California will use $895,000 and $252,000, respectively, for work in riparian areas.
Riparian Area Maintenance Plans
Maintenance prescriptions are included in environmental assessments (EA) that are developed
to provide utilization of forest commodities such as timber and grass. An EA for a timber sale, for example, can include direction for width, location, and treatment in allowable stream management zones. An example follows.
Two swale drainages within unit (Wilcox timber harvest unit 10) will need SMZ protection. Northern drainage is very boggy at upper end and will need SMZ located 25 ft. back from edge. No harvesting should be allowed within bog. Below bog, a 150 ft. SMZ should be sufficient around drainage. Select harvesting can be performed but avoid yarding through zone. Along southern drainage, a 200 ft. SMZ should be retained. Select removal of timber can also be performed if 50% of crown cover is retained. Yarding should again be avoided within the SMZ.
Boundary modification along southern edge of unit (Wilcox timber harvest unit 6) ephemeral drainage from south corner 18+50 to 21+50. Move boundary upslope 50 ft. to avoid impacting adjacent drainage. Allow harvesting of decadents within modified area but retain understory and prohibit equipment (USDA Forest Service 1981b).
The funds devoted to protecting riparian areas are not as easily tracked as are improvement funds. In fiscal years 1980 and 1981, approximately $2,172,000 and $2,845,000, respectively, were obligated for watershed and fish and wildlife assistance in the management of the national forest timber resource in California. This is approximately 21% and 31%, respectively, of their total budgets. A good portion of these funds were probably related to riparian area maintenance.
Discussion
Results of changes in riparian area management direction are slowly being realized. Even though, as early as 1966, the Pacific Southwest Region had begun to recognize that riparian areas needed special management direction, national direction did not emerge until 1980. Prior to 1980, commodity targets for forest products were developed through single-purpose resource management plans, such as forest timber management plans, under coordination requirements outlined in multiple-use plans. Multiple use plans were developed in the 1960s and early 1970s with limited interdisciplinary input. Prior to the current planning emphasis, in only a few cases have these multiple-use plans been updated. Thus, conflicts for use of riparian areas were not uncommon.
FS policy for managing riparian areas allows for management of, as well as protection of, riparian resources. This national direction is being integrated into forest land and resources management plans due for completion in 1983. These plans will determine each national forest's capability to produce forest products while applying this recent national direction. Capabilities will be combined into regional capabilities which in turn are combined into national capabilities. This will be the earliest that recent changes in riparian area management will be reflected in targets assigned to national forests.
How this may effect or change commodities is not clearly known at this time, but an indication may be the preliminary options being considered on the Six Rivers National Forest. Land areas delineated as stream management areas comprise 49,000 ha. (121,000 ac.) or about 13% of the forest not in wilderness. Under previous multiple-use plans, about 8,900 ha. (22,000 ac.) were designated as Water and Travel Influence Zones. Of the 19 billion board feet standing timber volume, 14% occurs in SMZs. Under options being considered, about one million board feet would be scheduled for removal from the SMZ. Under the previous plans, one-half million board feet were scheduled for harvest from the Water and Travel Influence Zone. Thus, areas being delineated for riparian area management have increased, and the rate of removal of timber from these areas has decreased.
Future Needs
National forest land and resource management plans will allocate areas for riparian resource management. This management will probably include programming of commodities, such as timber and grazing, to be realized as part of the riparian management prescription. The FS has not had much experience in designing management prescriptions of this type. The agency needs to know what a healthy riparian area should look like and be able to describe this condition in terms familiar to resource personnel applying vegetation management practices, such as silviculturists or range managers. This would allow the design and programming of vegetation manipulation harvests through a systematic, integrated process that is compatible with riparian area management objectives.
Further, monitoring techniques need to be developed to test the results of planning prescriptions, or to verify their design. Research is also needed to develop methods to inventory and assess riparian area resource values. Without a common process to describe the physical and biological character of riparian areas, a standard description of condition and treatment requirements is not feasible.
Summary
The FS in the Pacific Southwest Region has been implementing various intensities of management direction for protecting riparian areas since the mid-1960s. However, targets for commodities are assigned at the national level and have not changed significantly during this time
period. Thus, conflicts between competing uses have occurred within riparian areas.
FS direction published nationally, between 1979 and 1981, strengthens regional direction. The national direction provides for protection and improvement of riparian areas while still utilizing commodities, such as timber and grazing, from riparian areas.
National forests are analyzing their capabilities to produce commodities under this direction, as compared to targets determined prior to its issuance. This is the first opportunity to adjust commodity targets since the development of multiple-use plans and single resource plans of the 1960s and early 1970s. Individuals interested in having input to the analysis should make a point to review forest planning documents.
Literature Cited
Pacific Southwest Region, USDA Forest Service. 1979. Water quality management for National Forest System lands in California. USDA Forest Service, Pacific Southwest Region, San Francisco, Calif.
USDA Forest Service. 1975. Classification of streams. R-5 Supplement 15, Forest Service Manual 2536.1. USDA Forest Service, San Francisco, Calif.
USDA Forest Service. 1976. Stream protection measures. R-5 Supplement 17, Forest Service Manual 1521. USDA Forest Service, San Francisco, Calif.
USDA Forest Service. 1979. Prescription and environmental analysis of Trail Creek, Inyo National Forest. USDA Forest Service, Bishop, Calif.
USDA Forest Service. 1980. Riparian areas. Amendment 26, Forest Service Manual 2526. USDA Forest Service, Washington, D.C.
USDA Forest Service. 1981a. Analysis and evaluations for floodplain management and wetland protection. Amendment 31, Forest Service Manual 2527. USDA Forest Service, Washington, D.C.
USDA Forest Service. 1981b. Wilcox timber sale environmental analysis. USDA Forest Service, Shasta-Trinity Natinal Forest, Redding, Calif.
Protecting Stream Environment Zones to Preserve Water Quality in the Lake Tahoe Basin[1]
Judith E. Unsicker, Charles A. White, Michael R. James, and James D. Kuykendall[2]
Abstract.—Stream environment zones can provide effective natural removal of pollutants in precipitation runoff which would otherwise adversely affect the waters of Lake Tahoe. Human disturbance of some stream environment zones in the Tahoe Basin has drastically reduced their treatment capability. Activities of the California Regional Water Quality Control Board for protecting and restoring stream environment zones are discussed.
Introduction
Lake Tahoe, located at 1,897 m. elevation on the California-Nevada border (figure 1), is celebrated for its size, purity, clarity, and color. It is one of the largest high-altitude lakes in the world, with a volume of 155 billion cubic meters. The immense volume of the lake, and the relatively small size of its watershed (which discharged very low levels of sediment and nutrients to the lake under natural conditions) account for its outstanding water quality. The watershed includes 63 tributary streams. These streams, together with associated marshes, meadows, and riparian woodlands, are known to local planners as "stream environment zones" (SEZs).
Much of the Lake Tahoe Basin is in public ownership, but development of private lands, including large marsh and meadow areas throughout the basin, has been intensive during the last 25 years. About 10% of the watershed has been urbanized or otherwise disturbed. Increased residential and commercial development has been paralleled by increased phytoplankton productivity in open waters and nearshore periphyton growth. Phytoplankton primary productivity in 1980 was approximately twice that observed in the mid-1960s (Leonard and Goldman 1981).
These changes in productivity are the result of increased nutrient loadings to the lake caused by the increases in erosion and urban runoff flows which accompanied the development. In addition to these direct increases in nutrient loading, the disturbance of SEZs actually causes a reduction or complete loss in the capability of many SEZs to reduce nutrient levels in precipitation runoff through natural filtration, sedimentation, and adsorption processes (Tahoe Regional Planning Agency 1977; California Water Resources Control Board 1980).
The California Water Resources Control Board (State Board) and the California Regional Water Quality Control Board, Lahontan Region (Regional Board) are the state agencies responsible for protecting the water quality of Lake Tahoe and its tributaries through policy making, planning and enforcement activities. These boards cooperate with a number of federal, state and local agencies, including the bistate Tahoe Regional Planning Agency (TRPA), which recently adopted a bistate water quality plan. This paper summarizes State and Regional Board efforts to protect SEZs in the Lake Tahoe Basin—for their intrinsic value and for the protection of Lake Tahoe.
Definition and Importance of Stream Environment Zones
In 1971, the USDA Forest Service (FS), cooperation with the TRPA, mapped the soils a geomorphic characteristics of the Lake Tahoe Basin. This information was subsequently used by the FS and TRPA to construct a land capability system. Land capability was defined as: "the level of use an area can tolerate without sustaining permanent damage through erosion and other causes" (Bailey 1974). The system includes seven classes, with Class 1 being those lands which should be kept in their natural state a Class 7 lands rated the most tolerant of distur-
[1] Paper presented at the California Riparian Systems Conference. [University of California, Davis, September 17–19, 1981].
[2] Judith E. Unsicker is Environmental Specialist, Michael R. James is Senior Water Resources Control Engineer, and James D. Kuykendall is Supervising Water Resources Control Engineer; all are with the California Regional Water Quality Control Board, Lahontan Region, South Lake Tahoe, California. Charles A. White is Regional Administrator, Hazardous Material Management, Department of Health Services, Berkeley, California.
Figure l.
Map of Lake Tahoe Basin, showing
watershed boundaries (after Tahoe
Regional Planning Agency 1977).
bance (table 1). For each class, a maximum recommended percent coverage from developmental activities (e.g., paving, roof area) was prescribed as part of the land capability system. Class 1 lands were further broken down into three subclasses: 1a—high erosion hazard lands; 1b—lands with poor natural drainage; 1c—lands with fragile flora and fauna. Class 1b lands were defined to include "stream channels, marshes, flood plains, and meadows" (ibid .).
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SEZs, as defined in a later study (Tahoe Regional Planning Agency 1977), are essentially equivalent to Class 1b lands, although the determining criteria have been expanded in some respects. As mapped for the TRPA Water Quality Management Plan (ibid .), SEZs include the broadest of the following limits: streams, lakes, ponds; areas of alluvial soil; the 100-year floodplain; areas of riparian vegetation; a minimum buffer strip (7.5 to 30 m. [25 to 100 ft.]) with width dependent upon stream order (figure 2).
Figure 2.
Idealized stream environment zone (SEZ), showing
criteria used in determining boundaries (after
Tahoe Regional Planning Agency 1977).
SEZs in the Lake Tahoe Basin are important both as examples of comparatively rare ecosystems (e.g., the quaking bog at Grass Lake), and as fish and wildlife habitat. The Western Federal Regional Council Interagency Task Force (1979) termed SEZs "key wildlife habitats". The ability of SEZs to remove pollutants from precipitation runoff was measured by the TRPA (Tahoe Regional
Planning Agency 1977) and by the Environmental Protection Agency (EPA) (Morris etal . 1980). The TRPA study showed 94% removal of suspended solids, 74% removal of total nitrogen, 86% removal of total phosphorus, and 72% removal of iron as runoff passed through an undisturbed SEZ.
The EPA study compared SEZs having different kinds and amounts of disturbance, and concluded that meadowlands can provide effective treatment of runoff under certain circumstances. Sheet flow, as opposed to channelized flow, results in the best treatment; beaver dams may aid in achieving such flow. Extensive grazing alters the filtration capability of meadow lands, and may accelerate leaching of soil nutrients. The authors emphasized the importance of monitoring during storm events; the most dramatic reductions in sediment and nutrients were associated with storms rather than with monitoring of runoff at regular intervals.
The History of Human Influence on Stream Environment Zones
The Lake Tahoe Basin provided summer hunting and fishing grounds for the Washoe and Paiute Indians; a number of important archaeological sites are associated with SEZs. Early white settlers pastured their livestock in basin meadows. Much of the basin was logged in the nineteenth and early twentieth centuries. Early resorts were usually associated with riparian zones. All of these activities must have altered SEZs to some extent. However, extensive permanent disturbance began only in the 1950s and 1960s with the development of the Tahoe Basin as a center for winter skiing and casino gaming. These attractions stimulated road construction and residential and commercial development, most intensively at the south shore of the lake. Much of this construction took place in SEZs and included an airport, golf courses, sewerlines, a sanitary landfill, and a quarry, as well as motels, shopping centers, and residential areas on filled SEZ land. The most drastic alteration was the dredging and filling of 140 ha. (340 ac.) of the Truckee Marsh to create the Tahoe Keys subdivision. The Western Federal Regional Council Interagency Task Force (1979) estimates that since 1900, 35% of the riparian streamside zones, 50% of the meadows, and 75% of the marshes in the Lake Tahoe Basin have been lost to development. Between 1969 and 1979 alone, 25% of the marshes were developed.
All of this development produced a variety of disturbances including channelization and rerouting of streams, increased streambank erosion, disturbed soil and vegetation with loss of natural nutrient filtration capability, increases in impervious surface and surface runoff; and additions to surface waters and groundwaters of fertilizers, pesticides, and deicing agents. By the early 1970s over 40,000 dwelling units and an additional 30,000 vacant lots existed in subdivisions which were approved and constructed prior to the development of the land capability system. In some urbanized areas, total coverage exceeded 90%.
As the more level private lands (largely SEZs) were developed, demand grew for construction on steeper slopes (capability classes 1–3). Sewering of the basin by the early 1970s facilitated development on soils which were unsuitable for septic tank/leachfield systems. On many class 1 lands, where land coverage should be limited to 1%, coverage currently exceeds 50%. Development of these fragile lands led to increased sedimentation in SEZs, even when there was no direct encroachment on the SEZ.
Table 2, from the TRPA study (Tahoe Regional Planning Agency 1977), compares the water quality of tributaries of Lake Tahoe with disturbed and undisturbed watersheds. Further documentation of the siltation problem was provided by several other investigators (California Resources Agency 1969; Kroll 1976; Glancy 1976). All of these studies demonstrated that sediment and nutrient discharge was much greater from disturbed than from undistrubed watersheds. Furthermore, these studies provided evidence that sediment and nutrient yields from watersheds undergoing development have a tendency to increase markedly as construction activities encroach on lower capability lands. Present sediment and nutrient loadings to Lake Tahoe are estimated to be equivalent to those from an undisturbed watershed 10 times the size of the Lake Tahoe Basin.
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Work by the Tahoe Research Group (e.g., Goldman 1974) showed that suspended sediments could stimulate algal growth both as sources of dissolved nutrients and as substrates for heterotrophs which increase the rate of nutrient cycling.
Two studies by the State and Regional Board staffs contributed to the understanding of the effect of construction on sediment levels. Baker and Davis (1976) sampled benthic invertebrates in streams in and near the Tahoe Basin, above and below disturbed areas including subdivisions, road cuts, ski trails, and a large unpaved parking lot. Compared to reference stations, stations downstream of disturbed areas showed significant decreases in numbers, diversity, and
standing crop of benthic macroinvertebrate organisms.
White and Franks (1978) compared sediment and nutrient loadings to streams from the poorly-planned Rubicon Properties subdivision on the west shore of Lake Tahoe with loadings from the carefully planned Northstar-at-Tahoe development just north of the Tahoe Basin. In the former development, roads, driveways and homesites had been graded with little or no attempt at erosion and drainage control. Road cuts at Rubicon were up to 30–40% and 24 m. (80 ft.) high. Full buildout of Rubicon Properties would lead to an eventual 55% land coverage within the subdivision, although the land capability system would restrict development of such high hazard (class 1) lands to only 1% coverage. These disturbances, and later the installation of sewerlines, contributed sediment to Lonely Gulch Creek, which flows through the subdivision. Total sediment loadings were 100 times natural background levels with drastic impacts on benthic invertebrate populations.
At Northstar-at-Tahoe, the ski area and condominiums were located away from SEZs and high erosion hazard lands, and "best management practices" (BMPs) for erosion and drainage control were employed from the beginning. Sediment loadings after construction were estimated to be only two to three times background levels, and there was very little impact on benthic invertebrates of Martis Creek. One of the major conclusions of the work conducted by White and Franks (ibid .) was that the most important BMPs for the protection of water quality in a SEZ are limitation of development activities to conform to land capability and exclusion of significant development activities from the SEZ itself.
History of Water Quality Planning
In the mid-1960s, concern over the nutrient contribution to Lake Tahoe from domestic wastewater led to negotiations between California and Nevada. These negotiations eventually resulted in the export of sewage and solid waste from the basin, and the creation of the bistate TRPA. The Regional Board's Lake Tahoe Policy (California Regional Water Quality Control Board, Lahontan Region 1967) was concerned mainly with the sewage issue. It recognized the siltation problem, and supported land-use control actions by the State Legislature and local governments. However, it provided relatively little authority for Regional Board enforcement authority. A 1970 addendum to the policy, and the Water Quality Control Plan (Basin Plan) adopted in 1975 included prohibitions on the discharge or threatened discharge of wastes, including earthen materials, to Lake Tahoe and its tributaries, or within their 100-year floodplains. At that time, the land-use planning agencies, the TRPA, and the California Tahoe Regional Planning Agency (CTRPA) enacted ordinances which downzoned many of the SEZs and regulated grading, vegetation disturbance, and shorezone construction. However, the political situation led to "grandfathering" of development rights, and frequent granting of variances. Encroachment into SEZs continued.
In 1974 the TRPA was designated by California and Nevada as the "Section 208" planning agency for the Tahoe Basin under the Clean Water Act. In 1977 TRPA released a draft Water Quality Management Plan which identified development in SEZs, on high erosion-hazard lands, and in excess of land capability coverage limits as the major sources of water quality problems in Lake Tahoe and its tributaries. This plan recommended strict controls on new development and remedial erosion- and drainage-control projects to remedy impacts of existing development. Unfortunately, the final plan lacked commitment and funding for implementation of these controls. The State Board revoked TRPA's Section 208 planning designation and prepared its own water quality plan for the California portion of the Tahoe Basin (California Water Resources Control Board 1980). The Regional Board was given responsibility for implementing this plan. The major provisions of the State Board plan have been incorporated into the amended bistate plan recently adopted by TRPA. The Regional Board will continue to implement the State Board plan in California.
Prohibitions on Development
The State Board plan, pursuant to authority granted by Sections 13170 and 13243 of the Porter-Cologne Act, prohibits discharge of sediment and other waste materials from new subdivisions, and from any new development or construction activities which occur in SEZs or exceed land capability coverage limits, or which are not offest by remedial erosion- and urban runoffcontrol measures for existing problems. The prohibitions effectively preclude development on land capability classes 1, 2, and 3, where coverage limits are 1–5%. Approximately 7,100 lots in California, 2,100 of them in SEZs, are affected by this prohibition. The Regional Board may grant a variance from the prohibitions for projects found to be reasonably necessary for public health, safety, or recreation; or for implementation of the Nonattainment Air Quality Plan (California Air Resources Board 1979). An example of such a variance was granted for a proposed bicycle trail through a SEZ—part of the regional transportation system recommended by the Air Quality Plan. All possible mitigation and offset measures would be required for such projects.
The State Board plan directs local governments, or, alternatively, the Regional Board, to adopt offset policies specifying the amount of correction of existing problems to be required as a condition of approval of new development. The policies could require phasing development each year dependent upon accomplishment of erosion control work to date, and/or collecting an offset fee from each developer. Offset could include financial or institutional contributions toward the restoration of disturbed SEZs. Offset mea-
sures are to be over and above the remedial projects required by the State Board plan.
No offset policies have been adopted to date. However the TRPA has recently established a mitigation fee schedule for construction projects in the Lake Tahoe Basin. These fees meet most of the requirements of the offset strategy contained in the Lake Tahoe Basin Water Quality Plan. Mitigation fees for a single family house on high capability land, for example, would be $750. These fees will generate revenues of about $700,000 per year for the construction of erosion and urban runoff control projects in the California portion of the Lake Tahoe Basin.
In practice the development prohibitions in this plan are being enforced mainly by local and regional governments. The Regional Board participates in their development review processes at the staff level, and makes its own findings in the cases of proposed variances and waste discharge requirements.
Waste Discharge Permits
The Regional Board has the authority to issue waste discharge requirements under California law, or National Pollutant Discharge Elimination System (NPDES) permits under federal law for any activity involving potential discharge of wastes into the state's waters. Under the State Board plan, waste discharge requirements may be issued for single family homes as well as for commercial and public projects in the Lake Tahoe Basin. Such permits may prescribe specific erosion and drainage control measures, set limitations for chemical constituents in surface runoff, and/or require reporting of failure of controls to the Regional Board. Lack of compliance with waste discharge requirements may result in cleanup and abatement orders, cease and desist orders, or judicial enforcement by the state Attorney General.
The State Board plan directs the Regional Board to revise discharge permits for sewage agencies in the Tahoe Basin to preclude their serving new development which is in violation of the development prohibitions in the plan. These revisions are in progress. The State Board plan also directs the Regional Board to issue NPDES permits for storm drains into Lake Tahoe.
Remedial Erosion and Drainage Control Projects
The State Board plan includes a priority list of remedial projects to be undertaken by federal, state, and local agencies over a 20-year period. They include revegetation of areas stripped of vegetation, mechanical stabilization and revegetation of oversteepened and unvegetated roadway slopes, stabilization of eroding dirt roads, roadway shoulders and ditches, and storm drainage controls. The State Board has allocated $10,000,000 for these projects, to be used as matching funds for EPA Clean Lakes Grant money and local funding sources. To date over $2,000,000 of projects are in the process of being funded. None of the present projects directly affects SEZs. However, all erosion and urban runoff control projects are expected to create substantial reductions in the levels of sediment and nutrient discharges to the SEZs of the watersheds in which the specific projects are located. In the future these funds may be used directly for major SEZ restoration.
Monitoring
The State and Regional Boards are participants in a comprehensive interagency monitoring program which also includes the University of California, Davis, Tahoe Research Group; the California Department of Water Resources; the California Department of Transportation; the FS; and the USDI Geological Survey.
Algal productivity in nearshore and offshore waters of Lake Tahoe, as well as precipitation chemistry, flows, and water quality of tributary streams are being measured in this monitoring effort. Baseline data being collected now will aid in evaluation of the effectiveness of the control measures discussed above.
In 1981 the Regional Board expects to initiate its own surface runoff monitoring program which will include disturbed and undisturbed watersheds, individual commercial discharges, and storm drain systems. This program will be used by the Regional Board to obtain a more accurate assessment of the impacts of development and intense urbanization on the water quality of Lake Tahoe and of the SEZs of the Lake Tahoe Basin.
Restoration of Disturbed Stream Environment Zones
Where encroachments into SEZs have been permitted in the last decade, in most cases some level of mitigation measures have been required to offset the effects of the encroachment. Such measures, as specified in waste discharge requirements adopted by the Regional Board, include stabilization of soils disturbed during construction, and installation and maintenance of facilities to filter virtually all precipitation runoff from man-made impervious surfaces.
The FS has taken the lead in watershed restoration activities in the Lake Tahoe Basin. Significant projects to date have included leachate control at an abandoned landfill in a SEZ, restoration of natural water levels in a partially drained bog, and revegetation and installation of drainage controls in a meadow where casino development had begun.
SEZs will be a high priority for FS acquisition under the Santini-Burton program, which provides money for the buyout of environmentally sensitive lots. Additional money for public acquisition of SEZs and other fragile lands could
be available from a proposed California bond issue. The City of South Lake Tahoe is considering buying SEZs with park funds. Acquisition under these proposals would be on a willing seller basis, although it has been suggested that public agencies could acquire SEZs through the power of condemnation.
Other possible means of facilitating preservation and restoration of SEZs include transfer of development rights, easements, and amortization and eventual removal of existing structures (Tahoe Regional Planning Agency 1975).
Man-Modified Stream Environment Zones
The State Board plan recognizes that some SEZs have been so drastically altered that they no longer exhibit the characteristics of SEZs, and that restoration may be impractical. It allows the Regional Board to reclassify such areas, permitting further development provided adequate offset and mitigation measures are undertaken. Such measures would appropriately include restoration of some of the lost SEZ treatment capability through correction of SEZ problems elsewhere in the basin.
In 1982 the Regional Board will be asked to consider whether or not, or under what conditions further development of the Tahoe Keys subdivision should be permitted. If continued development is allowed, mitigation and offset measures might include one or more of the following:
1) continued operation and/or expansion of the existing water treatment and circulation system for the Tahoe Keys lagoon;
2) use of the remaining portions of the Truckee Marsh for natural treatment of surface runoff from developed areas;
3) restrictions on construction, landscaping, and gardening practices to minimize nutrient loadings to surface waters from runoff and groundwater percolation;
4) financial and/or institutional contributions to erosion and drainage control projects elsewhere in the basin—including restoration of sheet flow over meadows in channelized portions of the Upper Truckee River drainage, or correction of runoff problems in the urbanized Tahoe Valley drainage (both drainages were originally tributary to the Tahoe Keys area).
Conclusion
State and federal nondegradation regulations require that the existing high quality of Lake Tahoe's water be preserved, and enhanced if possible. Development restrictions and remedial control measures being implemented in the Tahoe Basin are believed to be absolutely necessary to prevent further degradation of water quality in the lake and its tributaries. The State Board plan emphasizes that further restrictions on growth and additional remedial projects are needed to reverse the degradation which has already occurred. The TRPA is now evaluating existing data in order to determine environmental threshold carrying capacities for a number of parameters including water quality. It will revise its regional plan, including land use controls, to reflect the limits. It is to be expected that protection and restoration of SEZs will continue to have high priority.
Literature Cited
Bailey, R.G. 1974. Land capability classification of the Lake Tahoe Basin, California-Nevada. 32 p. USDA Forest Service/Tahoe Regional Planning Agency, South Lake Tahoe, California.
Baker, J.A., and W.E. Davis. 1976. Siltation evaluation investigation for the Lake Tahoe Basin. 58 p. California Regional Water Quality Control Board, Lahontan Region, South Lake Tahoe, California.
California Air Resources Board. 1979. Lake Tahoe Basin control strategy revisions to State of California implementation plan for the attainment and maintenance of ambient air quality standards. 268 p. with appendix. California Air Resources Board, Sacramento.
California Regional Water Quality Control Board, Lahontan Region. 1967. Lake Tahoe water quality control policy. 38 p. California Regional Water Quality Control Board, Lahontan Region, Bishop, California.
California Regional Water Quality Control Board, Lahontan Region. 1975. Water quality control plan, North Lahontan Basin (6A). 533 p. California State Water Resources Control Board, Sacramento.
California Resources Agency. 1969. Sedimentation and erosion in the Upper Truckee River and Trout Creek watershed, Lake Tahoe, California. 50 p. California Department of Conservation, Sacramento.
California State Water Resources Control Board. 1980. Lake Tahoe Basin water quality plan. 378 p. California State Water Resources Control Board, Sacramento.
Glancy, P.A. 1976. A reconnaissance of streamflow and fluvial sediment transport, Incline Village area, Lake Tahoe, Nevada. USDI Geological Survew Water Resources Information Series Report 23, Carson City, Nevada. 47 p.
Goldman, C.R. 1974. Eutrophication of Lake Tahoe emphasizing water quality. EPA 660/3-74-034. 408 p. US Environmental Protection Agency, Corvalis, Oregon.
Kroll, C.G. 1976. Sediment discharge from highway cut slopes in the Lake Tahoe Basin, California. USDI Geological Survey, Water Resources Investigations 76-19. Menlo Park, California. 90 p.
Leonard, R.L., and C.R. Goldman. 1981. Interagency Tahoe monitoring program first annual report, water year 1980. 100 p. Tahoe Research Group, Institute of Ecology, University of California, Davis.
Morris, F.A., M.K. Morris, T.S. Michaud, and L.R. Williams. 1980. Meadowland natural treatment processes in the Lake Tahoe Basin: a field investigation. 180 p. US Environmental Protection Agency, Environmental Monitoring Systems Laboratory, Las Vegas, Nevada.
Tahoe Regional Planning Agency. 1975. TRPA 208 program, draft work element report. 243 p. Tahoe Regional Planning Agency, South Lake Tahoe, California.
Tahoe Regional Planning Agency. 1977. Lake Tahoe Basin water quality management plan (amended 1981). 4 volumes and amending ordinances. Tahoe Regional Planning Agency, South Lake Tahoe, California.
Western Federal Regional Council Interagency Task Force. 1979. Lake Tahoe environmental assessment. 240 p. Western Federal Regional Council, San Francisco, California.
White, C.A., and A.L. Franks. 1978. Demonstration of erosion and sediment control technology, Lake Tahoe region of California. EPA 600/2-78-208. 405 p. US Environmental Protection Agency, Cincinnati, Ohio.
Resource Allocation Issues Associated with Maintaining Instream Flow from Wastewater[1]
James R. Vilkitis and Donald R. Woodley[2]
Abstract.—The Chorro Creek study area lacks a comprehensive interagency water management plan. Programs and policies that relate to the missions of the various institutions and agencies involved in its management appear to be crisis oriented. The re-allocation of a water resource use through upgrading of a secondary treatment facility illustrates this approach to planning.
Introduction
At the inception of this study, the authors planned to use the Chorro Creek watershed as a case study area for resource allocation problems associated with competitive uses of a scarce resource: water. The planned approach was to review historical and present consumptive uses of water in the watershed, relative to instream flow and influence upon the riparian system. Of particular concern were the competing uses of water among the private and public riparian landowners during the dry season and the processes by which these uses were allocated water.
At the time, there appeared to be a plethora of information available from public agencies involved with water and its use and from the numerous reports of the watershed's resource. These could be used to construct a water management plan and water budget for the watershed. Upon investigation into the baseline sources, however, it became apparent that much of the information was not available, incomplete, or of poor quality. As a result, the case study deals only with factual information gleaned from public documents; hearsay was unsatisfactory and expert opinion was relied upon only when the source could be documented. Questions related to groundwater storage and yields have not been addressed, simply because adequate data that may be used for rational decisions do not exist.
For these reasons, the study concentrated on Chorro Reservoir (hereafter refered to as the Reservoir) and the waste water treatment plant at the California Men's Colony (WWTP), for which there appear to be enough historical data to give insight into water management of the study area.
Study Area
The main stream of Chorro Creek flows in a northwesterly direction. The 122-sq. km. (47-sq. mi.) watershed is the larger of two basins that drain into Morro Bay on the central coast of California, San Luis Obispo County. The watershed is bordered on the northeast by the Santa Lucia Range and to the southwest by a series of volcanic peaks known as Park Ridge. Two of the peaks (Black Hill and Cerro Cabrillo) form a narrow, through which the creek drains (fig. 1.)
The valley, 0.8 km. (0.5 mi.) wide in some places, varies from rolling hills covered with range grasses to relatively steep slopes at the divides. Three categories of land use were identified. 1) Commercial/residential, which includes Camp San Luis Obispo of the California National Guard (CNG), Cuesta College, and the California Men's Colony (CMC), comprised less than 10% of the area. 2) Agriculture, primarily pasture, comprised approximately 50% of the area, with less than 10% devoted to irrigated crops. 3) Idle land made up the remainder and was in general vegetated, with varying stands of chaparral, conifers and hardwoods. The denser vegetation was located on steeper slopes and in the draws of the basin. There was no urban land (housing developments) in the valley. The agricultural land had very high potential for multiple annual crop production with irrigation. Large landholders included private agriculture ranches, CNG at Camp San Luis Obispo (1,660 ha. [4,100 ac.]), national forest (1,730 ha. [4,276 ac.]), and U.S. General Services Administration (2,374 ha. [5,865
[1] Paper presented at the California Riparian Systems Conference. [University of California, Davis, September 17–19, 1981].
[2] James R. Vilkitis, Ph.D., is Natural Resource Manager, and Donald R. Woodley, Ph.D., is Hydrologist; both are at the School of Agriculture and Natural Resources at California Polytechnic State University, San Luis Obispo, Calif.
Figure l.
Chorro Creek watershed, San Luis Obispo County, California. (K. Frank.)
ac.]). The latter acquired the land some time after 1963.[3]
Chorro Creek is an intermittent stream with sections exhibiting no surface flow during the dry season (Chappell etal . 1976; Central Coast Regional Water Quality Control Board 1980). Most sub-basins experience flow during the winter and spring. The flow of the main stream is modified by consumptive uses during the dry season and continuously by effluent from the CMC's WWTP located at the junction of Pennington and Chorro creeks (fig. 1). The extent to which each of the sub-basins contributes water to the overall flow regime is not known (table 1.)
Streamflow has been monitored at the Canet Road crossing since November 1978, and on San Bernardo Creek for nine non-consecutive years (1960–65 and 1978–present). The data, however, indicate that the main stream is flashy and irregular. San Bernardo Creek appears to be more stable in its discharge. The gauging station is located upstream and not at the confluence of the San Bernardino with the Chorro (fig. 1). There are no baseline data for the other feeder stream, except for the records kept by CMC for the Reservoir and WWTP discharge.
Infiltration of rainfall appears to occur primarily in the thin residual soil (Henneke soil) of the headwater canyons. The lower alluviated valley (Salinas soil) generates a greater
[3] Machado, H.W. 1981. Personal communication. CNG, Camp San Luis Obispo, San Luis Obispo, Calif.
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proportion of the surface runoff due to layers of silts and clays near the surface.[4]
Geologic faults occur in the watershed (Carollo 1977). Their impacts on groundwater and groundwater movement are not known.
Procedures
No baseline data were generated through organized field research. Scientific literature, public agencies and institutions, private professionals, and local experts were consulted as sources of data. Pertinent information was compiled and assessed as to its validity.
Water resource statistics for the Reservoir were calculated from monthly records supplied by the CMC. Data were only assessed from January, 1962 through December, 1980 (study period), since these were the years that water was being imported from Whale Rock Reservoir on Old Creek and utilized by CMC, with subsequent discharge going into Chorro Creek. Whale Rock Reservoir is approximately 21 linear km. (13 mi.) northwest of the Reservoir. Averages in the tables should be approached with caution since in some cases they were calculated using the number of months where water flowed or was used. For example, during January of the study period, water flowed over the spillway 17 years out of the 19-year period; an average was obtained by dividing total flow over the spillway by 17. Results indicate the average flow for months of flow. Tables present all statistics related to flow and no-flow months.
Statistics for the WWTP were derived from "Repairs and Utilities Operation Log" records supplied by CMC, from July 1966 to June 1975. Reliable data for other time periods were not readily available.[5]
The study area is in a water-deficient region that experiences an average annual rainfall of approximately 560 mm. (22 in.), most of which (75%) falls between 1 December and 31 March. The allocation of water as a resource only becomes a management issue during that portion of the year when water is scarce and demand is great. This is identified as the "dry" period, which extends from May through November. Statistics related to this period are bracketed in the tables by heavier lines.
Results
Comprehensive and/or descriptive baseline data for the natural resources and land-use history of the watershed are not available. The environmental setting was established from information generated from sources specified above.
History
The Reservoir and WWTP are presently operated by CMC and are located within Camp San Luis Obispo, which is the property of the State of California. Established as a National Guard camp in 1928, its control was preempted by the federal government from 1941 to 1946 and from 1951 to 1953. During those periods structures were built that were the property of the federal government. Since 1965, the property has been under state control.
Chorro Dam was completed by the US Army Corps of Engineers (CE) in September 1941 as a device to regulate water imported from Salinas Reservoir (Santa Margarita Lake). Since it was a regulatory device, an appropriation permit from the State Water Resources Control Board (SWRCB), which authorizes construction of projects and uses of water, was not necessary. Over time the use of the Reservoir dam changed from regulation to storage and diversion. On 30 November 1955, the CNG filed an application (16757) for appropriation of water (storage and diversion) to the SWRCB. A permit (11527) was issued in 1958. Subsequently, the CNG made proof (19 July 1963) of a right to use water from Chorro Creek. A license (7844) for diversion and use of water was issued (4 August 1966) for irrigation, domestic, stock-watering, and recreational use. The conditions of the license were as follows:
[4] Mann, J.F. 1977. Correspondence. Consulting Geologist and Hydrologist, La Habra, Calif.
[5] Robasciotti, M. 1981. Communications. Waste water treatment plant, California Men's Colony, San Luis Obispo, Calif.
. . . and that the amount of water to which such right is entitled and hereby confirmed, for the purposes aforesaid, is limited to the amount actually beneficially used for said purposes and shall not exceed one and five-tenths (1.5) cubic feet per second by direct diversion to be diverted from about May 1 to about November 1 of each year for irrigation purposes and throughout the remainder of the year as required for domestic use and one hundred fifty (150) acre-feet per annum by storage to be collected from about October 1 of each year to about May 31 of the succeeding year.
The equivalent of such continuous flow allowance for any thirty-day period may be diverted in a shorter time if there be no interference with other vested rights.
Maximum withdrawal in any one year has been 92 acre-feet.
Licensee shall release or bypass a flow of at least one cubic foot per second into the natural channel of Chorro Creek below the point of diversion whenever the natural flow of the stream entering the Reservoir above the point of diversion is two cubic feet per second or more; and at least one-half of the natural flow into the reservoir shall be bypassed whenever that natural inflow to the Reservoir is less than two cubic feet per second. Releases of water from Licensee's storage will not be required to comply with the foregoing provision.
No devices were available within the Reservoir structure for implementation of the bypass requirement when the Reservoir was less than full. The requirement was met through effluent discharge from the WWTP until 1977, when the conditions of the license were brought to the attention of the California Department of Justice for clarification.
Through mutual understanding among representatives of the California Department of Fish and Game (DFG), CNG, and CMC, a bypass device (syphon) was constructed over the spillway to meet minimum flow requirements when the Reservoir was low. This was implemented during the 1977–78 water year.[6]
The Reservoir is located in the headwaters of Chorro Creek, 4.2 km. (2.6 mi.) upstream from where the creek crosses Highway 1 (fig. 1). Its surface area is approximately 2.8 ha. (7 ac.) with design storage of 150 acre-feet (AF). In 1980 it was estimated that, due to siltation, storage had been reduced to 65 AF. The Operating Engineers Training Trust (Local 12), under license from the CNG, is presently dredging the Reservoir to restore it to its original capacity; the license allows for the training of engineers.[3]
When the US Army preempted its right upon Camp San Luis in 1941, the Salinas Reservoir (approximately 20.9 km. [13 mi.] east) was constructed as the water source. Spent water, upon secondary treatment, was discharged into Chorro Creek (Frank 1963). Information related to the quantity of intake and discharge between 1941 and 1961 was not available. However, during the summer of 1961 the camp drew 500,000 gal. per day (gpd) from Salinas Reservoir to supplement the 300,000 gpd withdrawal from Chorro Reservoir (ibid .). Upon completion and operation of Whale Rock Reservoir in 1962, no water was used from the Salinas watershed.
The secondary WWTP was built on Chorro Creek, 12.9 km. (8 mi.) from Morro Bay, by the US Army at about the same time that the Reservoir was constructed. It was built to serve military purposes and designed to accommodate 1–2 million gallons per day (mgpd) sewage. The effluent discharged directly into Chorro Creek prior to 1 July 1979 was required to meet the following restrictions: 1) average maximum concentration for five-day biochemical oxygen demand (BOD) of 15 mg. per l.; 2) suspended solids of 25 mg. per l.; and 3) total coliform bacteria of 23 MPN per 100 ml.
Chorro Reservoir, the water treatment plant, the storage reservoir, and the sewage plant were leased to the Military Department of California on 1 July 1963; they are currently being operated by CMC under the lease (ibid .). After 20 years of operation through agreement with the former Department of Health, Education and Welfare (HEW), the structures revert to CMC.[7]
By 1969 the Central Coast Region Water Quality Control Board (CCRWQCB) pollution abatement program was being implemented. It was apparent that future effluent discharged at its present quality into Chorro Creek would be unacceptable.[8] As a result, CMC was looking for sources to utilize its effluent. California Polytechnic State University (Cal Poly), recognized the potential for irrigation through a feasibility study conducted in 1970, and, spurred on by the CCRWQBC effluent-recycling scheme, entered into a five-year (January 1972 to December 1976) interagency agreement (ID NO 69) with CMC to utilize the effluent. The nature of usage was not
[6] Younger, E.J. 1977. Correspondence. California Department of Justice, Sacramento.
[7] Salvato, C. 1981. Personal communication. Business Manager, California Men's Colony, San Luis Obispo, Calif.
[8] Gibson, J.C. 1969. Correspondence. California Polytechnic College, San Luis Obispo, Calif.
specified. In August, 1972, Cal Poly constructed a 50-AF storage reservoir to irrigate field crops (sugar beets, silage, corn, and hay). The water was not utilized during that very dry season because downstream landowners were dependent upon the effluent for irrigation. In subsequent years the water was utilized for instructional purposes, through the Agriculture Enterprise Management Program (AEMP) in which students do all of the operations from seedbed preparation to harvesting and marketing. About two-thirds of the field crops are grown on Cal Poly's Chorro Creek Ranch under this program.
The effluent usage arrangement worked so well that it was renewed intoto (ID No. SA69) in January 1977 for another five years, terminating 31 December 1981. In September 1979, a second reservoir (36 AF) was being filled. The philosophy of Cal Poly was to store more water at a time when the creek was high and allow more to go downstream during the dry season. About 100–200 AF of water is stored annually. This irrigates approximately 99 ha. (244 ac.) of land. Effluent is pumped year-round with highest usage occurring between April and September. Approximately 488 AF are used on the Chorro Creek Ranch. Of that amount, 293 AF (60%) comes from effluent; the remainder comes from two shallow wells on the ranch. Since irrigation was brought into the AEMP on Chorro Creek Ranch, 8,596 students spent 215,775 class hours in agricultural instruction.
Chorro Reservoir
Inflow into the Reservoir averages 180 AF per month, most of which (64%) occurs from January through April; 29% occurs during the dry period. The yield for the dry season, based on license restrictions for the average year, is approximately 332 AF. From January 1955 to April 1981, waterflow has been recorded every month. Statistics for the study period are presented by month in table 2.
Of the total flow into the Reservoir, approximately 72% flows over the spillway. Of the amount that spills, 77% occurs from January through April, with 17% occurring between May and November. During the dry period there is no flow over the spillway approximately 44% of the time. In addition, 76% of the no-flow months occur during the dry period (table 2).
Evaporation during the study period totaled approximately 1,097 AF; 72% occurred during the dry period (table 2).
Imported water from Whale Rock Reservoir accounted for 6,762 AF. It was imported 53% of the time. Of the total imported, 83% was brought in during the dry season. The initial safe annual yield for Whale Rock was calculated to be 8,900 AF. Through mutual agreement (1 November 1957), it was proportionally owned for distribu-
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tion on the following bases: City of San Luis Obispo 4,900 AF (55%); Cal Poly 3,000 AF (34%); and CMC 1,000 AF (11%). Figures presented in table 2 represent the water that is used in the Chorro watershed.[9]
At the 5 June 1974, annual meeting of the Whale Rock Commission, a presentation by California Department of Water Resources (DWR) regarding the Safe Annual Yield Study on the Whale Rock Reservoir led to the lowering of the annual yield. At present it is believed to be 2,300 AF per year.[10]
Waste Water Treatment Plant
Effluent discharge from the WWTP averaged close to 1 cubic foot per second (cfs) throughout the year for the study period. This figure is modified when the minimum and maximum flows are taken into account (table 3). Flow at or above 0.75 cfs generally occurs between the peak hours of 08:00–18:00 throughout the week, rising and falling continuously.[5] Accurate data for hourly flow have not been ascertained, nor are they readily available.
It appears that the effluent discharge has been decreasing through time. In a military report dated 1952, it was stated that low flow of 1 cfs had been reached.[3] Frank (1963) reported that ". . . the surplus effluent flows into Morro Bay." Surplus refers to water downstream from the sewage plant that has not been used for irrigation. In 1969 Cal Poly correspondence estimated discharge at 1.24 cfs.[11]
Robasciotti[5] states that in the last couple of years discharge has been around 0.77 cfs and has averaged up to 1.01 cfs. He believes that this low figure is due to leakage and that the average flow should be around 1.24 cfs.
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Upgrading the Waste Water Treatment Plant
Upgrading of the WWTP was partially brought about by an order (No. 75–50) from CCRWQCB, which prohibited discharge of wastewater into Chorro Creek after 1 July 1977.[12] The quality of the effluent did not come up to the requirements of the 1974 Water Quality Act.[13] The Clean Water
[9] Schneider, A. 1981. Communications, California Men's Colony, San Luis Obispo, Calif.
[10] Mayse, R. 1981. Communications. Whale Rock Reservoir, Cayucos, Calif.
[11] Johnson, C. 1969. Correspondence, Cal Poly, San Luis Obispo, Calif.
[12] Jones, K.R. 1976. Correspondence. Central Coast Regional Water Quality Control Board, San Luis Obispo, Calif.
[13] Dupius, R. 1981. Communications, State Water Resources Control Board, Sacramento, Calif.
Grant Program was an opportunity for CMC to upgrade its facility and effectively dispose of effluent within the watershed. Subsequently, procedures to qualify for the grant program were effected. The first two steps in the procedure had been implemented when a major stumbling block was encountered. DFG made known its concern regarding the steelhead trout fishery of Chorro Creek, and its dependence on effluent from the WWTP. Cessation of discharge, one of the alternatives, would allegedly severely alter a considerable portion of the trout's nursery habitat.[13] DFG indicated that at least 0.75 cfs must be maintained to support the fishery.
CCRWQCB staff responded, after review of the CMC draft project report, by considering to revise Order No. 75-50 to permit the discharge of highly treated wastewater to the creek. On 4 March 1977, representatives of DFG, SWRCB, CCRWQCB, and Toups Corporation (responsible for the preparation of an environmental impact report) met in Monterey to define minimum flow requirements necessary to maintain the aquatic habitat of Chorro Creek.[14] It followed that a resolution to the Clean Water Grant Contract regarding the discharge of 0.75 cfs was consumated through agreement of CMC and DFG (30 June 1978). This fulfilled Condition No. 3 of the Concept Approval letter and authorized payment beyond 50% of the step 2 grant.[15]
Some of the effluent characteristics of the upgraded plant are: 1) average maximum concentration for five-day BOD of 10 mg. per l.; 2) suspended solids of 10 mg. per l.; 3) total coliform bacteria 2.2 MPN per 100 ml.; 4) total phosphorus 0.5 mg. per l.; 5) ammonia 4 mg. per l.; and 6) nondetectable chlorine residual.
Water Balance
Total water input into the Reservoir during the dry period averaged 95 AF per month for the study period. Effluent discharge averaged 62 AF per month. The average loss to the system was 33 AF per month. The minimum flow bypass requirement of 0.75 cfs necessitated an average monthly discharge of 45 AF per month. This assumes that the flow of 0.75 cfs can be maintained throughout the day, which is not the case. The discharge fluctuates above and below this figure. The potential yield to Cal Poly is 17 AF per month. Statistics for the mean for imported water months (
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[14] Aleshire, R. Correspondence. Central Coast Regional Water Quality Control Board, San Luis Obispo, Calif.
[15] Rothenbaum, D. 1978. Correspondence. State Water Resources Control Board, Sacramento, Calif.
Discussion
Chorro Creek
It appears that throughout its history Chorro Creek has been an intermittent stream, and that the construction of the Reservoir and WWTP in 1941 created an artificial flow in the creek from water imported initially from Salinas Reservoir and later from Whale Rock. Statements such as:
We recognize that during dry months, most, if not all of the surface water flowing in the lower portion of the creek is from the Men's Colony. (Toffoli)[16]
Almost all of the water in Chorro Creek available to Hollister and other properties in the area consisted of treatment plant effluent. (Chesler)[17]
and:
The California Men's Colony Waste Water Treatment Plant, therefore, constitutes the most significant portion of the Chorro Creek flow during the summer months. (De Falco)[18]
lend strong support to the premise that the fishery may not have been able to survive without the effluent discharge since 1941. It also seems quite feasible that the use of water by Cal Poly through the interagency agreement since 1972 has not destroyed the fishery.
Wastewater
There are some legal restrictions on the ownership of wastewater within the watershed.[13] Basically, if the owner maintains control, as with CMC, it can do as it pleases with the water. When the water is abandoned into the creek, it becomes the property of the people of the state. "Abandoned" is a sticky term, but basically refers to no further intention of use.
Riparial rights deal with the natural flow which exists in the creek. It does not apply to imported water (waste water in this case), water released from storage, or water pumped from underground.[17]
Reservoir Bypass
The bypass license requirement at the Reservoir for maintenance of fish and wildlife habitat commenced 1 October 1977. During that month 750,000 gpd were syphoned over the spillway; the release was lost to evaporation, transpiration and ground infiltration before ". . . the flow reached Highway 1 . . ."[17] This point is approximately 2.4 km. (1.5 mi.) from the Reservoir.
Waste Water Treatment Plant Minimum Flow
The minimum flow requirement of 0.75 cfs during a dry year would require nearly all the effluent discharged from WWTP.[14]
Water Balance with Cal Poly
Approximately 50% of the water entering the Reservoir is imported (Whale Rock and storage); when the mean for the study period (
Water Management
A first step to be taken in managing the Chorro Creek watershed should be computation of a water budget. This would allow the manager to determine the relationship between water from precipitation and the outflow of water by streamflow, infiltration, and evapotranspiration. The water balance technique, as developed in the 1940s by C. Warren Thornthwaite, allows planners to utilize commonly available meteorological records to predict variables such as streamflow, groundwater recharge, or the effects of human activities on the ecology of the watershed.
Unfortunately, there are very few "commonly available, meteorological records" and other sources of information necessary for an adequate assessment of the Chorro Creek hydrologic system. No official meteorologic information has been collected in the watershed, although local residents have maintained records on precipitation, wind direction, and associated data on an irregular basis. However, there are over 100 years of precipitation records for the city of San Luis Obispo, and limited meteorological information is available from Cal Poly, the city of Morro Bay, and the San Luis Obispo County Engineer's Office. These data were made available for a preliminary appraisal of the Chorro Creek hydrologic basin.
[16] Toffoli, E.V. 1977. Correspondence. California Department of Fish and Game, Region 3.
[17] Chesler, A.A. 1977. Correspondence. State Water Control Board, Division of Water Rights, Sacramento, Calif.
[18] De Falco, P. 1977. U.S. Environmental Protection Agency, San Francisco, Calif.
The precipitation data are important. They are the basis for ascertaining the amount of water available in the drainage basin in a given year. Since recording rain gauges have not been in place in the proximity of Chorro Creek for the past several decades, existing data were used to estimate the average annual precipitation. Both the Theissen-weighted average and isohyetal methods were employed to portray and quantify the spatial patterns of precipitation. The results obtained by the Theissen method were evaluated as most representative of the area. These results, however, are strongly biased by the 110-year records of the San Luis Obispo station; these data commonly are the basis for filling information gaps in the Chorro Creek basin.
Evapotranspiration is the largest debit item in the Chorro Creek hydrologic budget. The evapotranspiration statistics are based on Class A evaporation-pan data collected at the Cal Poly weather station. Coefficients relating water use by each vegetation cover-type to the evaporation-pan information were derived from data developed by the University of California, Davis. The evaporation-pan information also provides the basis for calculated evaporation losses.
Surface runoff is a significant portion of the outflow from the Chorro Creek watershed. The calculated runoff is based on minimal recorded information. Incomplete runoff information was obtained for Chorro Creek and San Bernardo Creek. A gauge recently was placed on Chorro Creek, just downstream from the Camp San Luis Obispo boundary (fig. 1). Significant portions of the record for the 1978–79 and 1979–80 water years are missing. Seven years of discharge records were obtained for San Bernardo Creek. Unfortunately, both the main stream flow and the tributary flow are regulated above the respective gauges. This is important since the gauge information cannot reflect natural stream runoff. Residents of the area report that, prior to the construction of impoundments and other regulating measures, after-the-rainy-season flow in the stream was usually absent. These reports may be verified by well data which appear to place the piezometric surface below the streambed. If this information can be verified, Chorro Creek can be shown to be an effluent stream and intermittent in its natural state.
The available streamflow data were plotted on a precipitation hydrograph to obtain runoff/precipitation relationships. This methodology was used to establish that runoff in an average precipitation year may be expected to range between 18.51 hectare meters (HaM) and 25.49 HaM. The midpoint of the range was selected for the drainage basin hydrologic budget.
Data supplied by DWR, the Whale Rock Commission, and the several municipal and industrial water users were utilized to provide the remaining information presented in table 5.
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Water Budget
As with any budget, the hydrologic income and expenditures should balance. However, the calculated inflow exceeds the outflow in the Chorro Creek budget by about 0.57 HaM. This is a relatively small amount of water in this drainage basin. No attempt was made to "adjust" the respective inflow and outflow items to a balance. The difference is simply allocated as "other uses" on the debit side. This amount of water could be easily absorbed by any of the larger inflows or outflows, or it may be retained in the groundwater.
The questions of groundwater storage and yields were not included in this budget, simply because adequate data do not exist which may be used for rational evaluations. Data which will allow construction of analytical models will promote a better understanding of the groundwater basin, the surface water system, and the relation-
ship between the two. It is impossible to provide competent estimates of the available surface water or groundwater yield without this data.
Summary
The Chorro Creek watershed is a water-deficient area. There is a greater potential demand than natural supply. Conflicts exist among competitive users for imported water—the appropriation of which has not been established. Effective resource management requires sound baseline data to evaluate the resource potential and use. It also necessitates a comprehensive understanding of the integrated needs of the competitive users. At this time there appears to be no movement toward a comprehensive watershed management plan, nor interagency or cooperative agreement for implementation of a management scheme. Mechanisms exist to resolve some of the conflicts among agency users and subsequently allow more flow downstream during the dry season. One approach, through cooperative agreement, is to allow more storage during the rainy season. There is ample public land available for the construction of a storage reservoir. The water could be used for low-flow augmentation of the stream and irrigation. Another approach would be to maintain effluent holding tanks. They could serve as a reservoir to equalize streamflow and for irrigation water.
A third approach would involve interagency and cooperative agreement from local and state governments to utilize effluents from outside the watershed (e.g., Morro Bay, San Luis Obispo) in the development of an aquaculture program. The National Aquaculture Act of 1980 (PL 96-362) could be used as the vehicle for construction of stabilization ponds to be used not only to purify water but to harvest biomass. The water, once polished, could serve for low-flow augmentation, irrigation, and groundwater recharge.
Acknowledgments
This case study has involved contact with many and diverse agencies, both public and private. As such, scores of individuals supplied much-needed information, some willingly, others not so willingly. We are grateful for all the help we received and apologize for the discomfort we may have, in particular cases, induced. We deeply appreciate all the support and help provided by the SWRCB, the Division of Water Rights, the Division of Water Quality, CMC, the State Clearing House, DFG, Cal Poly, the city of Morro Bay, the city of San Luis Obispo, and all others that we may inadvertently have not mentioned.
Literature Cited
Carollo, J., Engineers. 1977. Draft EIR for Morro Bay-Cayucos Wastewater Facilities. Walnut Creek, Calif.
Central Coast Regional Water Quality Control Board. 1980. Order No. 80-42, NPDES No. CA0047856 adopted 24 November 1980, for California Department of Corrections, California Men's Colony, San Luis Obispo County. 7 p. Central Coast Regional Water Quality Control Board, San Luis Obispo, Calif.
Chappell, P.P., J.L. Lidberg, and M.L. Johnson. 1976. Report to the State Water Resource Control Board summarizing the position of the Department of Fish and Game on Water Application 24120. California Department of Fish and Game Region 3. 39 p.
Frank, A.F.W. 1963. Statement of mission. US Army Garrison, Camp San Luis Obispo, Calif. T/D 6A-6015.