9.0 LAND MANAGEMENT PLAN

Transcription

1 9.0 LAND MANAGEMENT PLAN 9.1 RANGELANDS Existing Conditions A detailed description of the physical conditions of the six leases and the current grazing practices is presented in Section for the six affected leases: Twin Lakes, Thibaut, Blackrock, Independence, Islands, Lone Pine, and Delta leases. Ecosystem Sciences (October, 2001) conducted an assessment of the rangeland conditions on each lease, as described in the report Owens Range Assessment 1999, Whitehorse Associates. For the assessment, Ecosystem Sciences mapped soil and hydrologic conditions for each lease based on methods of the National Resource Conservation Service (NRCS), and compiled vegetation and species composition data for the leases from the LADWP Inyo County Cooperative Vegetation Study (Green Book, 1990). The soil maps were used to identify the hypothetical potential plant production. These data were then compared to the existing vegetation to determine the production status of the existing rangelands that is, are the rangelands producing more or less than their theoretical potential. This assessment was based only on forage grass production. Rangeland conditions were expressed using the following assessment classes for mesic and arid pastures separately: Class 1: The rangeland mapping unit is producing 75 percent or more of its potential Class 2: The rangeland mapping unit is producing 50 to 75 percent of its potential Class 3: The rangeland mapping unit is producing 25 to 50 percent of its potential Class 4: The rangeland mapping unit is producing less than 25 percent of its potential The results of the assessment indicate the rangeland conditions on the leases range from Class 4 to Class 1. Trend is defined as the direction of change in range condition ( A glossary of terms used in range management. Society for Range Management, 3 rd edition, 1989). Trend of range condition is typically evaluated by taking repeated measurements of vegetation or soil attributes over periods of time. Trend can be classified as being upward (improving), downward (declining), or stable (no significant change). DWP has monitored trend in selected range communities throughout the Owens Valley since This long-term monitoring program has involved the use of permanent photo point stations with photos taken to document qualitative changes in range condition over time. From a qualitative perspective, these photos have been valuable in showing the influence that yearly precipitation can have on local and regional vegetation conditions. Trend monitoring for this project will involve quantitative and qualitative approaches. A subset of the long-term monitoring sites will be retained to allow for a qualitative evaluation of future data sets in terms of the influence of climatic conditions and land use changes. Permanent sampling transects will be established at several of the long-term sites mentioned above. In addition, permanent transects will also be established at several new locations within representative Los Angeles Dept. of Water & Power and EPA 9-1 Lower Owens River Project Draft EIR/EIS

2 management units in the LORP area. Nested frequency sampling (Interagency Technical Reference, BLM/RS/ST-96/ , 1996) and cover class estimates will be used at all permanent sampling transect locations. Sampling will also take place in areas designated as livestock exclosure areas. Data will be summarized following the procedures outlined in the Interagency Technical Reference. Trend data will be referenced to Potential Community Classification (NRCS database for Benton Owens Valley and Parts of Inyo and Mono Counties, California 1998) as well as to that collected from exclosure areas and areas of different management regimes within the project area Potential Impacts The proposed land management plans would modify grazing practices in riparian and upland areas on six LADWP leases in order to complement the habitat enhancements anticipated with the re-watering efforts under the Riverine-Riparian Habitat System. New riparian pastures and new riparian and upland utilization rates would be established. Other actions include protection of rare plant populations, establishment of off-river watering sources to reduce use of the river and off-river ponds for cattle watering, and monitoring of grazing utilization throughout the lease to ensure that grazing rates maintain the long-term productivity of the rangelands. These actions will result in environmental benefits to riparian resources and rangeland conditions. However, there are several unintended and incidental impacts associated with the proposed land management practices, as described below. This analysis was prepared by LADWP rangeland specialists. Under the proposed land management program, the intensity, location, and duration of grazing will be managed by forage utilization rates. Grazing will cease and cattle will be removed from riparian pastures when the utilization of forage in riparian pastures has reached 40 percent on benchmark riparian sites. For upland areas, maximum herbaceous forage utilization will be 50 percent if grazed during the active plant-growing season (April 1 to October 1). However, when grazing occurs during the active plant growing season and the pasture or field is rested for at least 31 continuous days during the active plant growing season, the forage utilization can be increased to 65 percent. Utilization criteria are being placed on leases to help with the goal of maintaining or improving range trends for each individual lease. Under adaptive management, if the desired trend is being met with utilization at the upper-targeted limit, the allowable utilization may be moved up. Conversely, if the trend is downward under the proposed utilization criteria, utilization may be adjusted down on a lease-by-lease basis. (see Section for description of trend monitoring). As a consequence of this approach, the overall grazing strategy should facilitate maintenance or improvement of current range trends. In addition, developing more stockwater will attain better animal distribution, and more fences will offer increased opportunity to rotate livestock. Implementation of the LORP, with its associated Best Management Practices and habitat improvements, should maintain or improve range conditions. Plant and soil conditions on the leases would improve due to these actions, resulting in a beneficial impact to rangelands (Class IV). The proposed land management program would not result in any adverse impacts to range conditions. As such, mitigation measures are not required. Los Angeles Dept. of Water & Power and EPA 9-2 Lower Owens River Project Draft EIR/EIS

3 9.2 BIOLOGICAL RESOURCES Existing and Future Anticipated Conditions The primary sensitive biological resources that occur on the leases include the riparian and aquatic habitats of the Lower Owens River (mostly degraded due to lack of flows); seasonal and perennial wetlands such as alkali meadows and freshwater marsh; elk herds; and scattered rare plant populations. The aquatic and riparian habitats along the river will be substantially enhanced in terms of extent, diversity, and productivity due to rewatering. New and enhanced habitats along the river are expected to attract more riparian breeding birds and support a more productive game fishery. The creation of new flooded areas and wetlands in the Blackrock Waterfowl Habitat Area is expected to increase the number and variety of resident and migratory waterfowl, shorebirds, and other water-associated birds. Finally, increased flows to the Delta Habitat Area are also expected to increase wetland and riparian habitats, and attract more shorebirds and waterfowl. Over time, the variety and abundance (in terms of numbers and geographic distribution) of sensitive biological resources in the various leases are expected to increase due to the LORP Potential Impacts Wetlands, Wildlife, and Rare Plants New riparian pastures will be established that are either excluded from grazing or, in most cases, used only from December through April and with a targeted utilization rate of 40 percent. The new riparian pastures are listed below in Table 9-1. Overall, about 900 acres would be removed from grazing due to the presence of rare plants or the pupfish, and about 19,000 acres of riparian pasture would be established and grazed in a manner compatible with promoting healthy a riparian condition, as described above. Lease TABLE 9-1 SUMMARY OF RIPARIAN PASTURES AND EXCLOSURES Current Grazed Pasture (acres) Proposed Riparian Pastures (acres) Proposed Pastures with Seasonal Restrictions or Exclosures (acres) Twin Lakes 4,912 1,667 The existing 1.6-acre rare plant enclosure for the Nevada oryctes (Orcytes nevadensis) will be reconstructed. Blackrock 32,657 14,540 Four rare plant exclosures will be established for the Inyo County star-tulip and the Owens Valley checkerbloom. Maintain current fencing around Well 368 where the Owens Valley pupfish occurs. Thibaut 5, Grazing will be prohibited from the 847-acre riparian exclusion zone for at least 10 years. A new 211-acre pasture will be created along the east side of the Aqueduct to protect populations of the Inyo County star-tulip and the Owens Valley checkerbloom. It will be grazed every year from October 1 to March 1 or 65 percent, which- ever comes first. Los Angeles Dept. of Water & Power and EPA 9-3 Lower Owens River Project Draft EIR/EIS

4 Lease Current Grazed Pasture (acres) Proposed Riparian Pastures (acres) Proposed Pastures with Seasonal Restrictions or Exclosures (acres) Island 21,657 1,760 0 Lone Pine 7, Delta 7,110 0 A 15-acre riparian exclosure will be created within this lease to be used as a monitoring control. * Source: Grazing management plans for individual leases prepared by Ecosystem Sciences In general, implementation of the proposed grazing management actions (i.e., creation of riparian pastures; modification of utilization rates in both riparian and upland pastures; and creation of rare plant, wetland, and waterfowl exclosures) would reduce any potential current grazing impacts to existing biological resources on most leases. Beneficial impacts include increased plant production and cover in riparian areas, which would provide more food for small mammals and birds, and cover for ground-nesting birds. Cattle would graze riparian areas for a shorter period of time, resulting in less frequent disturbance to ground-nesting birds; hence, the proposed management actions would result in beneficial impacts to riparian resources (Class IV). The application of appropriate grazing strategies in the LORP project area will complement the habitat enhancements anticipated along the river and in the Blackrock and Delta areas where a greater diversity and abundance of aquatic and terrestrial species are anticipated. There are several sensitive plant species that occur within the LORP project area and on LADWP leases. These species are described below. Inyo County star-tulip (Calochortus excavatus). This herb occurs in grassy meadow and moist places with alkaline soils in the Owens Valley, primarily in alkali meadow and alkali shrub meadow. Populations are scattered throughout the valley, west of the Owens River. Populations occur on the Thibaut and Blackrock leases. The Inyo County star tulip is included in the California Native Plant Society rare plant inventory as a rare and endangered plant (Skinner and Pavlik, 1994). It has no federal status. Owens Valley checkerbloom (Sidalcea covillei). This plant is endemic to the Owens Valley, occurring in scattered populations west of the river (Figure 26). It occurs in moist to wet alkali meadows. The Owens Valley checkerbloom is a state listed endangered species. It has no state or federal status. Populations occur on the Thibaut and Blackrock leases. Nevada oryctes (Oryctes nevadensis). This species is restricted to sandy soils in desert sink scrub and shadscale scrub habitats. Known populations in the Owens Valley occur primarily near Lone Pine, although there is a single population on the Twin Lakes lease. This species is considered rare and endangered in the California Native Plant Society rare plant inventory (Skinner and Pavlik, 1994). It has no state or federal status. The following sensitive species are known to occur in Owens Valley, but have not been recorded on LADWP lands and are not expected based on habitat preferences and the lack of sightings by LADWP, Los Angeles Dept. of Water & Power and EPA 9-4 Lower Owens River Project Draft EIR/EIS

5 County, and Ecosystem Sciences personnel over many years of field investigations. These species are included in the California Native Plant Society rare plant inventory (Skinner and Pavlik, 1994), but have no state or federal status. Geyer s milk-vetch (Astragalus geyeri) Sand linanthus (Linanthus arenicola) Sagebrush loeflingia ( Loeflingia squarrosa) The existing populations of Inyo County star-tulip, Owens Valley checkerbloom, and Nevada orytces would be protected by rare plant exclosures on the Twin Lakes, Blackrock and Thibaut leases. Grazing will be excluded from the Twin Lakes rare plant enclosure, while grazing will be prohibited in the other exclosures during the flowering period of the species (April-June). These populations have been subjected to grazing for decades and have persisted, despite removal of plants by grazing and trampling effects. A seasonal timing change in grazing is expected to improve the reproductive success and longterm survival of these rare plant populations. To the extent that this restriction is implemented, the impacts to these populations from future grazing are considered beneficial (Class IV). The only existing population of the endangered Owens Valley pupfish in the LORP project area occurs at Well No. 368, located on the Blackrock lease. LADWP will maintain the existing exclosure around the well and surrounding aquatic habitat where the pupfish population resides. 9.3 POTENTIAL IMPACTS ON ADJACENT BLM AND SLC GRAZING LANDS BLM Grazing Lands BLM s Bishop Resource Area of the Bakersfield District surrounds the LORP project area. The resource area is divided into nine management areas, three of which are lands surrounding the LORP - - Owens Valley, South Inyo and Owens Lake management areas. The Owens Valley Management Area (OVMA) encompasses 153,750 acres containing the Alabama Hills, three developed campgrounds, and areas of dispersed recreation use. Wildlife resources include mule deer, several springs and streams and tule elk calving habitat. The South Inyo Management Area (SIMA) consists of 65,000 acres. There is important wildlife habitat, including potential bighorn sheep habitat, and small stands of bristlecone pine. The Owens Lake Management Area (OLMA) contains 15,790 acres of BLM land near Owens Lake. It includes important tule elk calving grounds and habitat for several special status wildlife species. Guidelines for managing the various resources and activities in the resource area are derived from the Bishop Area Resource Management Plan (RMP), and BLM s Standard Operating Procedures. One of the primary activities on BLM lands is grazing. Grazing allotments are established throughout the Resource Area, and leased to non-federal parties. Livestock grazing occurs on 69 allotments in the Bishop Resource Area, with annual licensing of 35,261 AUMs. Allotment management plans are prepared for each allotment to establish grazing utilization rates and protection of other resources. These plans are developed based on federal grazing regulations and BLM rangeland policies contained in the RMP. Plant phenology of key forage species of livestock and wildlife is considered in determining grazing schedules. The average annual livestock utilization of key forage species is not allowed to exceed 60 Los Angeles Dept. of Water & Power and EPA 9-5 Lower Owens River Project Draft EIR/EIS

6 percent unless there is an Allotment Management Plan, which specifies a different level. When monitoring verifies that utilization levels exceed 60 percent, a change in livestock management practices is implemented, such as changes in grazing preference, season of use, or location of use. Salting and supplemental feeding locations are not located within ¼ mile of riparian zones, sensitive plant habitats, or sites that are highly susceptible to soil erosion. Livestock grazing is prohibited in unallocated areas or areas outside of existing allotment boundaries. Annual utilization checks are conducted during the grazing season on selected meadows and key wildlife habitats. Trampling of soils is monitored in conjunction with forage utilization to determine whether the limit of allowable grazing has been achieved. Most allotments on BLM land are adjacent to or intermingled with lands controlled by the LADWP or the Inyo National Forest. On several allotments, the boundaries are not fenced. Numbers of stock, seasons of use, and range facilities and treatments are often cooperatively handled by means of MOUs, cooperative agreements, and other less formal arrangements between the agencies and the permittees. BLM s National Rangeland Management Policy established standard criteria for determining selective management categories for grazing allotments on public lands. An allotment s selective management category may change as resource conditions change or new information becomes available. The goal is to have as many allotments in the Maintain (M) category as possible. Maintain (M) Category Criteria present range condition is satisfactory; the allotment has moderate to high resource production potential and is producing near that potential, with no serious resource use conflicts or controversy. Opportunities may exist for positive economic return from public investments; present management is accomplishing the desired results, and any other appropriate criteria. Improve (I) Category Criteria present range condition is unsatisfactory; the allotment has moderate to high resource production potential but is not producing near that potential, and serious resource use conflicts or controversy exist. Opportunities exist for positive economic return from public investments; opportunities exist to achieve the allotment s potential through changes in management, and any other appropriate criteria. Custodial (C) Category Criteria present range condition is not a factor, the allotment has low resource production potential and is producing near that potential, limited resource use conflicts or controversy exist. In a letter to LADWP dated February 29, 2000, the BLM expressed concerns regarding the proposed grazing management plans, and specifically, the proposed riparian pastures and associated fencing. BLM is concerned that restrictions in grazing of riparian pastures and the relocation of water sources to areas away from the river (but nearer to BLM lands) could encourage cattle drift onto public lands that are adjacent to LADWP leases in the river corridor. There are no fences between LADWP and BLM lands. BLM is aware of drift that occurs under current conditions, and is concerned that the additional unauthorized grazing on federal lands could damage range conditions. The BLM grazing allotments that are located adjacent to LADWP leases are as follows and specific cattle drift issues are described below: Los Angeles Dept. of Water & Power and EPA 9-6 Lower Owens River Project Draft EIR/EIS

7 Twin Lakes Lease. BLM Black Mine Allotment (# 6023) assigned to 4- J Cattle Co. (Mark Johns) adjoins the Twin Lakes lease. BLM believes that cattle from the LADWP lease currently use Allotment # 6023 and that such use may occur outside the dates of BLM authorization. BLM states use is authorized in a given year from 10/16 to 2/28 or from 3/1 to 5/15. The specified use period actually corresponds very close with the grazing lease plan for the LORP. The public lands in allotment # 6023 are about 35 acres per AUM, which is low production and may likely be lower since the forage inventory is over 20 years old. Blackrock Lease. Approximately one-half section (at Black Jack Mine Section 1) of the BLM Allotment # 6023 adjoins the Blackrock Lease. The public lands adjoining this lease are partially unallocated for livestock grazing and have been for over 20 years. There is occasional cattle drift in early spring depending upon whether there is sufficient precipitation and resultant growth of annual forage species on the public land uplands. Some of this drift has been controlled by the placement of a cattleguard on the Mazourka Canyon Road and a drift fence from Kearsarge north to the hills at Snowcaps Mine. Cattle drift from the LADWP Blackrock Lease and subsequent grazing use of public lands can still occur south of the Mazourka Road along the alluvial fans. There are no historic fences in the area that could be reconstructed. The grazing capacity of public lands in this area range from plus acres per AUM (extremely low production), so BLM is very concerned about potential increased utilization of the allotment under the new lease management plans. The West Santa Rita Allotment #6048 assigned to Lacey & Son abuts the Blackrock Lease. The current season of use for this allotment is October 10 through December 31, at 100 percent federal range for 8 AUMs. Thibaut Lease. The grazing exclosure that incorporates the entire east boundary adjacent to this lease should benefit BLM and help eliminate drift of unauthorized livestock. Lone Pine Lease. The Ash Creek Allotment #6042 is located adjacent to this lease on the west of U.S. Highway 395. Delta Lease. There are scattered parcels of public land within the Delta Lease that are unallocated for livestock grazing. Due to the extremely low forage production on these public lands, the allotment could be adversely affected if additional grazing pressure occurs due to the proposed grazing management plan for the Delta lease. There are insufficient data to determine the magnitude of the potential cattle drift from LADWP leases onto adjacent BLM grazing allotments under current conditions, and under the proposed grazing management practices. This impact would not occur for all leases; it has the greatest potential to occur at the Thibaut, Blackrock, and Delta leases. The magnitude of the unauthorized drift is not expected to be substantial, nor would it significantly degrade BLM range conditions for the following reasons: Most of the LADWP lessees have the BLM allotments adjacent to their leases. As such, the same rancher is managing grazing on both LADWP and BLM lands, which will allow greater ability to prevent future unauthorized drift onto the BLM. Los Angeles Dept. of Water & Power and EPA 9-7 Lower Owens River Project Draft EIR/EIS

8 The utilization thresholds on LADWP leases are likely to be met and cattle removed prior to the allowable utilization rates on the adjacent BLM permits The forage on LADWP leases with their extensive riparian pastures, would be more attractive to cattle than the BLM permits with upland pastures and poorer forage, especially in dry years when annual forage production in upland areas is minimal. Hence, LADWP concludes that an increase in cattle drift would be nonexistent or minor and would not significantly affect the range conditions on public lands. This impact is therefore considered adverse, but not significant (Class III). The magnitude of this potential impact can be reduced through incorporating modified grazing and herd practices on LADWP leases adjacent to BLM allotments to reduce drift, without the installation of new fences (see Mitigation Measure LM-1) State Lands Commission Lands in the Delta The southern boundary of the Delta Lease has an unusual shape. A long narrow parcel of LADWP land extends 2.5 miles along the west side of the Delta (Figure 2-28), which is surrounded by state-owned lands under management by the State Lands Commission (SLC). No fence separates LADWP and SLC lands. The modified grazing practices on the Delta lease will not result in increased unauthorized drift onto SLC lands as compared to current conditions. The impact of cattle drift onto public lands would be similar to the one described above, and the same mitigation measure would apply. It should be noted that the lessee for the Delta Lease is currently negotiating an agreement with SLC concerning grazing on the state-owned lands Mitigation Measures LM-1 The grazing management plan for individual leases shall be modified to incorporate herd and grazing practices to reduce potential cattle drift onto public lands. These lease-specific measures shall be developed in consultation with BLM and shall include specific measures to discourage unauthorized drift, such as strategic placement of watering troughs and coordination of grazing rotation patterns between LADWP and BLM pastures. The effectiveness of these measures shall be evaluated in the LORP monitoring and adaptive management program. (NEPA mitigation) 9.4 OTHER IMPACTS THAT ARE CONSIDERED NEGLIGIBLE Installation of fencing to establish riparian pastures would have a negligible effect on native vegetation. Posts would be installed by hand crews working from small trucks that travel overland. No new roads would be constructed, nor would any grading or excavation be required. Minor mowing and brush clearing may be required at fence post sites, and along the alignment. The footprint of disturbance for each post would be several square feet. No permanent or irreversible damage to vegetation would occur, nor would the type of surface disturbance facilitate weed colonization. Stringing the fence would also occur by hand crews. Los Angeles Dept. of Water & Power and EPA 9-8 Lower Owens River Project Draft EIR/EIS

9 Fence installation is also not expected to adversely affect movement by elk, as the grazing management plans include provisions to create elk-friendly fences (Figure 2-17) along known elk trails. Fence installation will require use of small trucks; however, the emissions from the fencing program are not expected to represent a significant emission source. It will be a short-term emission similar to that caused by current routine rangeland management activities on the leases. The new fences are not expected to cause any visual impacts, as they will be difficult to see from paved public roads. Fencing is a common visual feature in the Owens Valley, and wire fencing presents a very diffuse visual image that does not generally detract from the landscape. All existing roads and trails on the leases that have been historically used by the public to access the river and off-river lakes for recreation (i.e., fishing, bird watching) would be maintained to allow free access. Gates or cattleguards would be installed to control cattle movement, but easy access for the public would be maintained; hence, no adverse impacts to public access and recreational uses are anticipated. Various cultural resources occur on the leases, including prehistoric and historic archaeological sites. The modification of grazing practices would generally reduce the overall intensity of grazing, and thereby reduce any ongoing disturbances (if any) to archaeological sites. The installation of fence poles was deemed an insignificant impact by the State Office of Historic Preservation (Far Western, 2001) because the physical damage from post installation is very limited and diffuse; hence, no adverse impacts to cultural resources are expected. Los Angeles Dept. of Water & Power and EPA 9-9 Lower Owens River Project Draft EIR/EIS

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