The Watershed at a Glance 139

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1 Watershed Old near Millville Lower near the town of Palo Cedro Foothill oak and rangeland, with Mount backdrop The Watershed at a Glance 139 The 27,000-acre Watershed (about the size of the state of Delaware) is a large, generally uncontrolled tributary to the located in eastern County. The watershed is unique in that land ownership is divided almost evenly among commercial forestland, commercial agriculture (predominantly cattle ranching), and small private residential properties, with minimal public ownership. The watershed includes five principal tributaries: North Fork, Oak Run, Clover, Old, and South Fork s. It provides important habitat for fall-run and late fall run Chinook salmon and steelhead. There are no major reservoirs, but numerous small dams divert water for irrigation and hydropower production. Management program efforts have focused on providing passage for anadromous fish, reducing risk of wildfire, and addressing concerns with seasonal low flow, temperature, and bacteria levels. 3 Bally Bully Choop Mt. 1 Lassen Pk. Chester Diamond Dyer Mt. North Yolla Bolly Mt.s Bt. Humboldt Summit South Yolla Bolly Mt.s 89 Mt. 32 Corning Bald Eagle Mt. 99 Mt. Ararat Pilot Pk. Eureka Pk. 32 Watershed Statistics Chico Watershed Size: 430 square miles Bloomer Hill 4 Watershed Length: ~40 miles Saddleback Mt. Willows Annual Average Precipitation: 2 to 6 inches Oroville Sierr Pike County Pk. 162 Snow Mt. Oregon Pk. 49 Bowm Gridley Elevation: Lowest 400 ft. Fr Black Bt. Highest 7,300 ft. 89 Colusa Sutter Buttes 99 Sutter Population: ~1,000 Williams Counties: Management Issues: salmon/steelhead, forest health/fuels management, aquatic/ riparian habitat, water quality, open space/land conservation 0 80 Grass Valley Yuba City 4 Auburn Watershed 16 Eastside Subregion Banner Mt. Nevada City 80 Miles Placerville Woodland Esparto 0 0 Davis Watershed within the Eastside Subregion PAGE 90

2 M S q uaw head Seasonal low flow in North L i t t l e C o w Hydrology Churn Co w er C o w. St i l l wa t Cr N or t Battle hb att le C r. Pa y nes Dams over 2 An tel op e 0 8 Miles B S a c ra m e nt From 1949 until the present, USGS has maintained daily flow records for at a gage located just upstream of the confluence with the. Average annual flow during this period of record is 69 cfs. The maximum peak flow was 48,0 cfs in November 1981 with a minimum of near 0 cfs in July ranks third behind and Stony for producing the largest peak floodflows in the northern Valley. It has been estimated that floodflows from the Watershed account for approximately 21% of the peak discharge for the between Dam and. Water rights in the Watershed are adjudicated (established by court decree), and there are approximately 278 recorded points of diversion. Water use is mostly for pasture irrigation, stock water, and hydropower (PG&E is in the process of decommissioning their hydropower facilities). These diversions significantly affect instream flow in the lower reaches of during the summer season. Hydrology in the Watershed Water Quality Both the Central Valley RWQCB and the Watershed Management Group have conducted monitoring in recent years. The primary water quality issues in the watershed relate to bacteria, temperature, and erosion/sediment discharge. There is one inactive, abandoned copper mine (Afterthought Mine); however, acid and metals draining from this site appear to have only localized impacts in North Fork. E. coli levels are a concern, given the extensive contact recreation use in this stream (swimming and tubing), and North Fork, Clover, Oak Run, and South Fork s are all 303(d) listed as impaired waterbodies for bacteria. Likely sources include domestic livestock, faulty septic systems, and wildlife. Temperature is an important factor in successful spawning and rearing of salmon and steelhead and in some years may be a problem seasonally for in-migration of adults (October and November) and out-migration of juveniles (April, May, and June). December 08 flood flow in North Concentrated livestock, a potential source of bacteria to Basset Irrigation Diversion Dam Ranch road erosion, a potential sediment source Filamentous algae growth in North Channel erosion, a common watershed problem PG&E hydropower operations, Kilarc Powerhouse PAGE 91

3 head Little watershed conifer uplands Vegetation The Watershed has diverse plant communities resulting from its varying topography, soils, and elevation change that ranges from 400 feet on the valley floor to above 7,000 feet in the forested uplands. Native plant communities are:»» riparian forest (1%);»» wetlands (marshes, vernal pools, and wet meadows) (1%);»» annual grasslands (4%);»» blue oak and foothill pine woodlands (48%);»» chaparral (1%); and»» coniferous forest (4%). Native plant communities in the watershed have been altered significantly by aggressive fire suppression, conversion for agriculture, and the introduction of invasive species (e.g., Himalayan blackberry, yellow star-thistle, Pampas grass). Historically, coniferous forests were open and park-like, whereas today s forests are dominated by dense, small-diameter, shade-tolerant trees with thick understory. This condition results in significant fuel loading and high fire danger. Battle Vegetation types in the Watershed Fish and Wildlife North Battle Annual Grass Blue Oak Woodland Mixed Chaparral Mixed Conifer Pine Forest Urban-Agriculture Three different groups of fish live in : anadromous, resident, and exotic. Anadromous species that migrate up the watershed to locations downstream of natural barriers include fall-run Chinook salmon and winter-run steelhead. Common resident species are rainbow trout (generally above 1,000 feet elevation), hardhead, pikeminnow, and sculpin. Exotic species known to occur in are large-mouth and smallmouth bass, carp, bluegill, brown trout, and brook trout. Fishery agencies have estimated that 9,000 female salmon potentially could use the 66 miles of streambed. Recent counts have been far below that potential, ranging from a few thousand to only a few hundred in the last couple of years. is a high-priority watershed in the basin-wide effort to increase anadromous fish populations, and restoration efforts will target concerns with instream flow, passage and screening of diversions, water temperature conditions, and habitat improvements. supports a large population of blacktail deer, but that herd is known to be in decline partly because of a reduction in early plant succession habitat (a principal food source for deer). Turkeys, bear, mountain lion, feral pigs, and more recently elk, are all well established in the watershed. Foothill oak and rangeland in the spring Fish passage problem (Millville irrigation dam on Clover ) Riparian vegetation on lower Successful deer hunter PAGE 92

4 head Livestock grazing in Watershed Little Battle North Battle Water Snow & Ice Urban Barren Deciduous Forest Evergreen Forest Shrubland Grassland Pasture Cropland Wetland Life in the Watershed Privately held lands dominate the watershed. At just over 30% of the land base, timber production is a significant commercial activity (major landowners include Roseburg Resources Company, Beaty and Associates, and Sierra Pacific Industries). Ranching and livestock production are a major agricultural component contributing to the rural character and country lifestyle so valued by residents of this watershed. The Williamson Act, which offers tax incentives for preservation of agricultural lands, is an important mechanism in maintaining the rural lifestyle, and currently about 7,000 acres in the Watershed are enrolled in that program. Residential development is centered around the small communities of Palo Cedro, Bella Vista, Millville, Oak Run, and. Outdoor activities such as camping, fishing, hunting, and ORV use are important pastimes for most residents and also significantly contribute to the local economy. The Latour State Forest is the largest public ownership in the watershed. Land use in the Watershed US Postal Service, Watershed cattle ranch PG&E Kilarc Reservoir PAGE 93

5 head Falls, natural fish barrier Management Objectives The CCWMG, together with the Western RCD, completed the Watershed Assessment in November 01 and the Watershed Management Plan in March 0. As discussed in these reports, the principal issues and management objectives for this watershed are:»» improve water quality by assisting with projects that implement improved management practices,»» improve water quantity by assisting with projects that enhance dry season instream flow,»» increase salmon and steelhead populations by implementing projects that improve aquatic habitat and provide safe passage for migrating fish,»» reduce forest fuel loading and the risk of catastrophic wildfire, and»» promote watershed stewardship through an active education and outreach program. Little Battle North Battle BLM National Forest Wildlife Area Land ownership in the Watershed Caltrans Highway bank protection project Management Organizations Active in the Watershed Watershed Management Group In response to concerns over water quality, fisheries, habitat loss, and wildfire threat, the Watershed Management Group was formed in 00 as a nonprofit 01(c)(3) organization with the mission of using the resources in the Watershed in a way that meets the needs of today without infringing on the needs of future generations. Western RCD provides administrative assistance and staff support to the organization. Grant funding was obtained to complete a watershed assessment and management plan, and in the past several years grant-funded projects have been implemented that include fish passage and screens on water diversions, strategic fuel breaks along transportation corridors, and improvements on irrigation canals for the purpose of increasing water use efficiency. Lower at Dersch Road Oak hardwoods and annual grassland PAGE 94