ECOSYSTEM MANAGEMENT PLAN
Action Plan and Concept Document
prepared for
Los Angeles Department of Water and Power
and
Inyo County
prepared by
Mark Hill and William Platts
PURPOSE
GOALS
ELEMENTS
WORK PROGRAM
REFERENCES
APPENDICES:
1. STUDY PLAN: IDENTIFICATION OF RIVER FLOW REQUIREMENTS
FOR FISH, WILDLIFE, AND RIVERINE-RIPARIAN HABITATS IN THE
LOWER OWENS RIVER, CALIFORNIA
2. LOWER OWENS RIVER PROJECT DATA BASE FOR THE DETERMINATION
OF STREAM FLOWS FOR FISH AND WILDLIFE (EXECUTIVE SUMMARY TO
PHASE II FLOW STUDY)
3. WATERSHED MANAGEMENT CONCEPTS
In 1993 the Los Angeles Department of Water and Power (DWP) and Inyo County, in cooperation with the California Department of Fish and Game implemented a detailed ecological study of the Lower Owens River (Hill et al. 1994) from the DWP's aqueduct intake to Owens Lake - approximately 65 miles of river channel and wetland habitat (see Figure A [Sorry, this figure is not available on the internet at this time.]). The original purpose of the study was to develop an EIR and mitigation plan for the Lower Owens River Project (LORP) which included establishing minimum streamflows for fish and wildlife values. The primary focus of the original LORP was on developing a healthy warm water fishery and on improving wetland habitat. The study, which was conducted in two phases, consisted of extensive data collection (Phase I) and controlled-flow modeling (HEC-2, HEC-6, HEP, PHABSIM, QUAL2E), resource mapping, GIS data base development, and associated biological (fish, wildlife, vegetation) and hydrological studies (Phase II). The protocol for Phase I of the study and the executive summary for Phase II of the study are attached to this plan as Appendices 1 and 2 respectively. The results of these studies set the stage for decisions on rewatering the Lower Owens River to achieve fish and wildlife goals.
One outcome of the studies is the recognition that the goal of simply achieving a healthy fishery and improving wetland habitat is too narrow. The studies show that a unique opportunity exists to reestablish a functioning riverine ecosystem throughout the Lower Owens River. This length of river and associated wetland areas throughout the Lower Owens Valley can provide substantial ecological benefits and sustainable development to all users (recreation, livestock, agriculture, diversion) if a holistic approach is taken.
It is apparent that the benefit of establishing a holistic ecosystem management program on the Lower Owens River represents a wise investment of time, money, and energy. In the Lower Owens River watershed, streamflow can be matched to groundwater and riparian habitat development, which can be connected to wetland habitats, threatened and endangered habitat conservation areas can be consolidated, biodiversity can be enhanced and recreational fish and wildlife values can be created that are unavailable anywhere else in the Owens Valley.
The scope and goals of the LORP have therefore been expanded to include sustainable development through a large-scale ecosystem management program that incorporates a variety of resource values and reestablishes the riverine-riparian ecosystem for the benefit of biodiversity, threatened and endangered species, recreational opportunities, and user groups. The Memorandum of Understanding (MOU), to which this plan is attached, sets forth the goals and commitments for the implementation of the LORP.
This plan describes the tasks and objectives for preparing a Lower
Owens River Project ecosystem management plan (LORP Plan), which will guide the
implementation of the LORP. The LORP Plan will cover all Los Angeles-owned land within the
approximate area shown on the map that is presented as Figure
A in the MOU ("Planning Area").
GOALS
The goal of the LORP will be to establish a functioning ecosystem (i.e., an ecologically healthy watershed). The heart of an ecologically healthy watershed is the riparian habitat (Decamps and Naiman 1989, Naiman and Decamps 1990) (see Appendix 3, "Watershed Management Concepts"). The riparian habitat is shaped by channel geomorphology, hydrologic pattern, spatial position of the channel in the drainage network, and the inherent disturbance regimes. Yet the riparian habitat affects, and is affected by, habitat dynamics, water quality, and the animal community. This strongly suggests that maintenance of riparian habitat in a healthy ecological condition is of fundamental importance for long-term ecological and socioeconomic vitality of the Lower Owens River watershed.
The available evidence suggests that ecologically healthy watersheds are maintained by an active natural disturbance regime operating over a range of spatial and temporal scales (Naiman et al. 1992). Ecologically healthy watersheds are dependent upon the nature of the disturbance (e.g., fire, landslides, channel migration) and the ability of the system to adjust to constantly changing conditions. This natural disturbance regime imparts considerable spatial heterogeneity and temporal variation to the physical components of the system. In turn, this is reflected in the life history strategies, productivity, and biodiversity of the biotic community (Naiman et al. 1992).
The natural disturbance regime in the Lower Owens River will consist of multiple streamflows emulating natural water-year events (wet, moderate, dry years). This natural disturbance regime will produce a dynamic equilibrium for riparian habitat, water storage, water quality, animal migration, and biodiversity resulting in resilient and productive ecological systems. The net result is an ecological system at the watershed scale which possesses a biotic integrity strongly valued for its long-term social, economic, and ecological characteristics.
The goal of an ecologically healthy Lower Owens River watershed is dependent upon rewatering the channel from the intake to the pumpback station with a multiple flow regime with a base flow of approximately 40 cfs and variable habitat flows of up to 200 cfs, as specified in the MOU, that will flood riparian areas. Groundwater (streambank storage and hyporheic zones under the floodplain) is an essential element in establishing an ecologically healthy watershed. Maintenance of the interaction of surface-groundwater for the benefit of the biotic community is particularly important in the development and maintenance of the wetlands associated with the LORP (Blackrock, Twin Lakes, Goose Lake, the Delta, etc.) within the watershed.
Development of a habitat conservation plan for indigenous threatened and endangered species (fish, wildlife, and plants) is another feature of the project planning process. (The definition of "threatened and endangered species" contained in the MOU shall also apply in this plan.) To the extent feasible, such a plan will include all such indigenous species and will consolidate and/or provide linkages and corridors between critical habitats in the Planning Area to reduce gaps and habitat discontinuity.
Inherent in the overall management of the watershed will be the promotion of biodiversity and sustainable uses. Inclusion of non-native species will provide fishing opportunities. Diverse recreational activities such as hiking, bird watching, boating, swimming, and hunting will be anticipated. To the extent feasible, land management plans will consider these and other recreational uses, as well as livestock grazing and irrigation strategies.
The ecosystem management plan for the Lower Owens River Project consists of a number of elements (see Figure B) which, when implemented, would reestablish the Lower Owens River riverine-riparian ecosystem for the benefit of biodiversity and threatened and endangered species, while providing for the continuation of sustainable uses, including recreation, water diversions, livestock grazing, agriculture and other activities and would achieve the other goals for the LORP. Table 1 identifies a list of "habitat indicator species" that represent the range of habitat conditions desired to be achieved for each of the areas associated with the four physical features of the LORP described in the MOU. Within each of these areas, the objective will be to create and maintain through flow and land management, to the extent feasible, diverse natural habitats consistent with the needs of the "habitat indicator species."
Consultation with the Parties to the MOU, agencies, DWP ranch lessees, and the public concerned with the development and implementation of the LORP will occur throughout the development and implementation of the LORP Plan.
Habitat Indicator Species
Owens River Riverine-Riparian System
Other species that will receive proper consideration are Owens pupfish, Owens tui chub, and Owens speckled dace.
Management Plan for the Lower Owens River Riverine-Riparian Ecosystem: This plan will provide for the establishment and maintenance of a continuous flow in the river channel to create and sustain healthy and diverse riverine riparian and aquatic habitats, and a healthy warm water recreational fishery with healthy habitat for native fish species. Diverse natural habitats will be created and maintained through flow and land management, to the extent feasible, consistent with the needs of the "habitat indicator species."
Wildlife and Wetlands Management Plans: These plans will address the Blackrock and Owens River Delta habitat areas, off-river lakes and ponds, and other riparian and wetland areas within the Planning Area to achieve the goals for these areas identified in the MOU and in this plan. Within each of these areas, the goal is to create and maintain through flow and land management, to the extent feasible, diverse natural habitats consistent with the needs of the "habitat indicator species."
Habitat Conservation Plan: This plan will identify conservation areas within the Planning Area which will be managed to facilitate restoration of threatened and endangered species to viable populations. The intent of this element is ultimately to achieve sufficient recovery of these species to warrant delisting them, while providing for the continuation of sustainable uses, including recreation, agriculture, and aqueduct operations.
Land Management Plan: This plan will address livestock grazing and other land uses within the Planning Area. In developing the plan, priority will be given to riparian areas, irrigated meadows and sensitive plant or animal habitats. The management plan will consider multiple resource values and will provide for management based on holistic management principles. The goal of the management plan will be to promote biodiversity and a healthy ecosystem, while allowing for the continuation of sustainable uses of the land.
Long-Term Monitoring and Reporting Program: This plan will identify monitoring sites and water flow gaging stations, and will describe a program for data collection, analysis, and reporting. The plan will provide information regarding the LORP to ensure its successful implementation by providing pathways to allow feedback to indicate where modifications to management are necessary.
II. Management Plan for the Lower Owens Riverine-Riparian Ecosystem
A. Refine estimates of the extent of potential riparian habitat along the river. Estimates will be refined for a base flow of approximately 40 cfs and a seasonal habitat flow of up to 200 cfs as specified in the MOU.
1. Calculate the variance in landform elevations measured along cross-channel
transects.
2. Calculate the variance in stream stage elevation predicted by HEC2 modeling.
3. Reevaluate criteria for predicting the extent of riparian habitat (i.e., surface
elevation relative to stream stage with an on-site review).
4. Predict maximum extent of riparian-wetland vegetation types, assuming minimum landform
elevations (estimated as one SD less than the mean) and maximum stream stage (estimated as
one SD greater than the mean).
5. Predict minimum extent of riparian-wetland vegetation types, assuming maximum landform
elevations (estimated as one SD greater than the mean) and minimum stream stage (estimated
as one SD less than the mean).
6. Prepare maps and data for both the minimum and maximum extent scenarios.
7. Produce a final vegetation modeling report.
B. Revise HSI models for wildlife values along the river.
1. Supplement model variable data as necessary including habitat characteristics and
landscape level features.
2. Model management actions.
3. Revise and refine habitat descriptions.
C. Develop Lower Owens River management plan.
1. Determine timing, magnitude, duration, and points of releases.
2. Address beaver concerns, dams, and influence on hydrology.
3. Identify channel preparation and conveyance facility needs.
4. Address tule and muck management concerns.
5. Conduct water quality sampling and address water quality during start-up along the
river and in the off-river lakes and ponds.
6. Establish hydrology recording stations.
7. Site supply ditch and aqueduct release point below the intake.
8. Address "island area" - channelize or leave as is.
9. Incorporate HCP (see below).
10. Evaluate groundwater effects from pumping and recharge.
11. Incorporate recreational activities.
12. Address Owens Lake issues.
13. Write a draft management plan (including figures and maps).
14. Produce a final management plan.
D. Consult with DWP and Inyo County on siting of pumpback system.
1. Conduct environmental evaluation of proposed location of pumpback system.
III. Wildlife and Wetlands Management Plans
A. Identify existing and potential riparian-wetland vegetation types on Los
Angeles-owned land within the Planning Area. This will include the
Blackrock and Delta habitat areas, off-river lakes and ponds, and all wetlands within the
Planning Area.
1. Acquire 1:24000 DEMs for Owens Valley and evaluate the feasibility of generating
contour maps from these files (generate contours if feasible).
2. Map existing vegetation types and structures (ditches and dikes) from 1:12000 photos.
3. Integrate existing soils information on the GIS.
4. Integrate features (e.g., culverts) that affect water distribution on GIS.
5. Predict water distribution based on previous tasks.
6. Estimate a water budget for the wetlands.
7. Predict distribution of wetland-riparian vegetation types as a time series.
8. Produce a final report.
B. Revise HSI models for wildlife values for all riparian-wetland areas within the Planning Area (as described in A above).
1. Supplement model variable data as necessary including habitat characteristics and
landscape level features.
2. Incorporate time-series predictions.
3. Model management actions.
4. Revise and refine habitat descriptions.
C. Develop wildlife management plan for all riparian-wetland areas within the Planning Area (as described in A above).
1. Determine configuration for wildlife habitat areas.
2. Determine management goals and objectives.
3. Determine water control techniques.
4. Identify habitat improvement opportunities.
5. Determine habitat maintenance requirements.
6. Determine the need for a pilot scale or controlled flow study.
7. Define project design, constraints, and expectations.
8. Integrate with grazing and other land management plans.
9. Integrate HCP.
10. Consider practical measures to minimize and control the abundance and extent of
deleterious species whose presence within the Planning Area interferes with the
achievement of the goals of the LORP.
11. Write a draft management plan (include figures and maps).
12. Produce a final management plan.
IV. Develop Habitat Conservation Plan (aquatic and terrestrial)
A. Establish goals and objectives.
B. Select indigenous threatened and endangered species for the plan (tier 1 and 2 species).
C. Determine boundaries of HCP and included habitat types.
D. Determine recoverability and attainability of delisting.
E. Integrate plan with watershed management goals.
F. Integrate T&E monitoring into overall monitoring plan.
G. Coordinate goals, objectives, management and monitoring responsibilities with USFWS and DFG.
H. Visit sites identified by USFWS as HCP areas.
I. Prepare draft HCP
J. Produce final HCP
V. Develop Land Management Plan
A. Establish range management and grazing plans.
B. Incorporate HCP.
C. Consider the effects of tule elk and riparian interactions.
D. Identify other resource activities that conflict with goals.
E. Resolve recreation activities, commercial uses, and conservation goals for sustainable use.
F. Write draft land use plan.
G. Produce final land use plan.
VI. Develop Long-Term Monitoring and Reporting Plan.
A. Select monitoring sites and establish protocols and intervals for data collection, analysis, and reporting.
B. Select appropriate target species and habitat characteristics for monitoring.
C. Incorporate HCP.
D. Perform adaptive management with monitoring results.
E. Establish pathways to allow feedback from monitoring to adaptive management plans.
F. Write draft monitoring and reporting plan.
G. Produce final monitoring and reporting plan.
VII. Evaluate impacts associated with the LORP and its alternatives including the configuration and location of the pumpback station and conveyance.
A. Species and habitats, HSI, HEP, IFIM outputs to be used as the primary tool to determine existing and future with-project conditions and to evaluate impacts of project alternatives and to guide mitigation actions.
B. Determine appropriate preliminary mitigation.
C. Write impact/mitigation report.
Decamps, H., and R.J. Naiman. 1989. Ecology of rivers. La Recherche 20:310-319.
Hill, M.T., W.S. Platts, S. Jensen, T. Hardin, and G. Ahlborn. Data base for the determination of stream flows for fish and wildlife in the lower Owens River. L.A. Dept. of Water and Power, Bishop, CA.
Naiman, R.J., T.J. Beechie, L.E. Benda, D.R. Berg, P.A. Bisson, L.H. MacDonald, M.D. O'Connor, P.L. Olson, and E.A. Steel. 1992. Fundamental elements of ecologically healthy watersheds in the Pacific Northwest coastal ecoregion. Pages 127-188 in, R.J. Naiman (editor), Watershed Management, Springer-Verlag, New York, NY.
Naiman, R.J., and H. Decamps, editors, 1990. The ecology and management of aquatic-terrestrial ecotones. UNESCO, Paris and Parthenon Pub. Group, Carnforth, UK.