State of the Yuba An Assessment of the Yuba River Watershed Prepared by: The South Yuba River Citizens League (SYRCL) April 2006 Contributing author: Fraser Shilling, UC Davis State of the Yuba—April 2006 Page 1 of 57 Table of Contents A. Developing Areas B. Population Changes I. Summary C. Roads II. Introduction D. Logging III. Water Quality Information from the Yuba River E. Mining Monitoring Program Special Issue: Mercury Contamination in Fish i. Water Temperature F. Dams and Diversions ii. Dissolved Oxygen VII. Conducting a GIS-based Watershed Assessment iii. pH (acidity/alkalinity) A. Why Consider the Landscape iv. Total Dissolved Solids (conductivity) B. What Parameters to Include v. Total Suspended Solids, Turbidity C. Method for Analyzing the GIS Data vi. Contaminants D. Construction of the “Knowledge Base” for a. Arsenic Assessing Watershed Condition b. E. coli i. Terrestrial Environment Special Issue: Algae in the Yuba River Watershed ii. Aquatic Environment IV. Historic and Contemporary Flows E. Results of Analysis Special Issue: Flows in the Yuba River F. Conclusions V. Land Cover in the Watershed VIII. Bibliography VI. Human Disturbances in the Watershed State of the Yuba—April 2006 Page 2 of 57 I. SUMMARY The Yuba River is located on the west slope of the northern Sierra Nevada and is a tributary to the Feather River. It pours down 3 main stems (South, Middle, and North) from granitic basins through forested canyons to the Sacramento Valley. The watersheds for the South, Middle, and North Yuba Rivers are impacted by a variety of human activities, while the rivers themselves are some of the most regulated in the state (in terms of flows). Water quality tends to be high, when compared to rivers in the Central Valley. The Yuba River Monitoring Program and other monitoring projects have found specific contaminants associated with certain creeks, while generally reinforcing the claim that the water of the Yuba River is clean. However, low flows and high temperatures on the South and Middle Yubas and a legacy of sediment from hydraulic mining have contributed to problems for the cold-water adapted aquatic communities. There are a variety of risks posed to the Yuba watershed from human activities. These include a) a high concentration of roads associated with rural housing development, logging, and recreation, b) a patchwork of ownership making watershed-scale decisions more difficult, and c) substantial water regulation and withdrawals from the basin. II. INTRODUCTION The North Yuba flows from the Yuba Pass area, past Downieville, where it is joined by the Downie River, to New Bullards Bar Reservoir. The Middle Yuba originates from springs near Meadow Lake, passes through Jackson Meadow Reservoir, and enters Englebright Reservoir near Rice Crossing. The South Yuba River begins near Castle Peak/Donner Pass, parallels Interstate 80 until it merges with Spaulding Reservoir, and cascades down 40 miles of canyon until it enters Englebright Reservoir near Bridgeport. There are more than 2,100 miles of streams, creeks, and rivers within the Yuba system. These range in elevation from around 9,000 feet at Castle Peak to under 100 feet in the Valley. They meander through steep-walled granite canyons, small towns, mined areas, conifer forests, oak woodlands, agricultural areas, and grasslands. The upper watershed receives over 80 inches of precipitation, much of which is as snow in the winter, while the lower (in the Valley itself) receives about 20 inches. Most people don’t think about watersheds very much, or if they do, aren’t always sure where they start or end. The Yuba “watershed” is that part of the landscape that rain or melting snow runs off and into the Yuba River or its tributaries. The edge of the watershed is the ridgeline, however broad and ill-defined, that determines whether precipitation goes into the Yuba tributaries, or some neighboring river basin, like the Feather or Truckee River basins. The creek or river at the bottom of a valley or swale is the recipient of the precipitation and is therefore affected by activities on the landscape from which the water originates. State of the Yuba—April 2006 Page 3 of 57 Human Activity in the Yuba River Watershed According to Wilson and Towne (1978), the Hill Nisenan occupied the Yuba basin until the mid-1800s (Anderson and Moratto, 1996). Several thousand individuals probably lived in villages in the foothills and mid-elevations, with seasonal residences at higher elevations. After the Gold Rush, most Native peoples had been killed or displaced by miners and settlers. There are no population estimates by watershed, but for Nevada County, the numbers oscillated between 10,000 and 20,000 residents from 1850 to 1950 (Duane, 1996). Since 1950, the number of County residents has increased five-fold to close to 100,000 people (Duane 1996). The economy of the Yuba watershed since European-American settlement has included gold mining, logging, construction, recreation, rural housing development, and various agricultural operations. The relative socio-economic ranks of the counties within the watershed has changed radically over the last 50 years (Hoffmann and Fortmann, 1996). In 1950, Nevada County was one of the poorest in the state (per capita income), while Yuba County was in the top third. By 1992, these ranks had essentially been reversed. Sierra County went from the top third to the middle third. The South Yuba and Deer Creek watersheds currently face a growth spurt in the “rural sprawl” that is spreading through the foothills from the Sacramento valley below. Nevada County is considered a recreation destination and a place for second and retirement homes. The prices of being an attractive place near Sacramento are fragmentation due to subdivision of parcels, grading the landscape for roads, driveways, and pads, and increasing demands for water and community services. The impact is likely to be felt by existing residents of the watershed as well as the natural resources and processes. Watershed Assessments The “State of the Yuba” report is essentially a “watershed assessment”. This includes evaluations of the human and cultural setting of the watershed as well as an evaluation of the condition of the water and landscape of the basin relative to numeric standards (e.g., drinking water standard) or “desired conditions”. Another way to think about this is a way to identify and prioritize places and processes in the watershed that may require restoration, increased management attention, or some other protective activity. Although there is no one standard way to conduct a watershed assessment, typically they are encyclopedia describing the condition of a part of the landscape that provides water to a particular water body. III. WATER QUALITY INFORMATION FROM THE MONITORING PROGRAM SYRCL has been water quality data from throughout the Yuba River watershed since 2001. The monitoring program is designed to detect impacts to waterways from natural and human activities in-stream and on the surrounding landscape. Results of the program at State of the Yuba—April 2006 Page 4 of 57 this time can show areas of potential impact from land-use, but is the data yet remains too limited to allow for statements about long- term trends in condition. Several waterways are potentially or actually impacted within the Yuba basin. For example, a tributary of the South Yuba, Humbug Creek, is listed under the Clean Water Act, 303(d) for sediment, mercury, copper, and zinc. The Upper Yuba is also considered a “priority watershed” for action by the state under the California Unified Watershed Assessment. There are many impacts within the watershed that contribute to these listings, including dams and diversions, abandoned mine lands, high road densities, and poor logging practices. The goals of the Yuba River Monitoring Program have been revised to meet the growing needs of the watershed: 1) To provide baseline river monitoring data for: assessing existing conditions of the Yuba River Watershed understanding medium and long-term river trends, including land use practices, restoration actions, impact of climate change providing input to long-term management questions, such as restoring salmon populations, geomorphic changes. 2) To empower citizens to be responsible stewards and advocates for river health. 3) To educate the larger Yuba Watershed community regarding trends and issues. 4) To serve as a model citizen-based river monitoring organization by: Maintaining an on-going pool of trained monitors Educating citizens in state-of-the-art stream monitoring collection techniques and their relationship to a healthy watershed. State of the Yuba—April 2006 Page 5 of 57 5) To assess, identify and prioritize restoration opportunities and projects; and to evaluate project impact and performance. 6) To evaluate Yuba water and habitat quality in terms of specific criteria. 7) To guide local watershed management decisions. The focus of the project is on habitat and chemical, physical and biological water quality measures that will identify the status of these aquatic resources. There are several components to SYRCL’s volunteer monitoring team. The monthly monitoring team collects periodic samples from all 33 sites (depending on weather and access). A subset of the monitoring team forms the Peak Flow Team. They collect the samples before, during and/or after storm events from priority sampling sites. Prioritization is based on a combination of site accessibility and position of the site in the watershed. A Macroinvertebrate Team collects aquatic insects from ten sites primarily on the South Yuba and three sites on the Middle and North Yuba. The monitoring teams have been extensively trained in water quality measurements, sampling, and riparian condition assessments. There are five to seven monitoring trainings each year. In addition, the River Monitoring Director accompanies monitoring teams every month in order to assess their techniques and to provide on-site training.