School Way Bridge Replacement Project Delineation of Waters of the United States February 24, 2010 Prepared for: Mendocino County Department of Transportation Attn: Park Steiner 340 Lake Mendocino Drive Ukiah, CA 95482 Prepared by: North State Resources, Inc. 5000 Bechelli Lane, Ste. 203 Redding, CA 96002 (530) 222-5347 51175 Delineation of Waters of the United States School Way Bridge Replacement Project BRLSZO 5910(039) Township 16N, Range 12W, Unsectioned Portion of Yokaya Land Grant Mendocino County, Redwood Valley, California USGS quadrangle February 24, 2011 STATE OF CALIFORNIA Department of Transportation Consultant Prepared by: Date: 2/24/11 Paul Kirk Botanist/Wetland Scientist North State Resources, Inc., Chico, CA (530) 345-4552 Local Agency Approved By: Date: Park Steiner Environmental Compliance Specialist Mendocino County Department of Transportation (707) 463-4363 Caltrans Approved By: Date: Brandon Larsen Associate Environmental Planner, Office of Local Assistance District 1, Caltrans (707) 445-6410 Caltrans SEP Approved By: Date: Deborah Harmon Senior Environmental Planner District 1, Caltrans (707) 445-6431 School Way Bridge Replacement Project Delineation of Waters of the United States S ection 1 Summary............................................................................................................................ 1 S ection 2 Project Location ................................................................................................................ 1 2.1 Proximity to Major Highways and Streets ................................................................ 1 2.2 USGS Hydrologic Unit ............................................................................................. 1 S ection 3 Environmental Setting ...................................................................................................... 2 3.1 Current/Recent Land Use .......................................................................................... 2 3.2 Site Topography and Elevation ................................................................................. 2 3.3 Climate ...................................................................................................................... 2 3.4 Hydrology/Hydrologic Features................................................................................ 2 3.5 Soil Map Units .......................................................................................................... 3 3.6 Habitat Types ............................................................................................................ 3 Barren ................................................................................................................. 3 Montane Riparian ............................................................................................... 3 Riverine .............................................................................................................. 4 Urban .................................................................................................................. 4 S ection 4 Methods.............................................................................................................................. 4 4.1 Field Delineation ....................................................................................................... 4 S ection 5 Results ................................................................................................................................ 5 5.1 Characterization of Delineated Features ................................................................... 5 Other Waters ....................................................................................................... 5 Wetlands ............................................................................................................. 6 Non-Jurisdictional Features ................................................................................ 6 5.2 Conclusion ................................................................................................................ 7 S ection 6 References .......................................................................................................................... 7 North State Resources, Inc. School Way Bridge Replacement Project February 24, 2011 i Delineation of Waters of the United States 51175 Figures Figure 1. Study Area Location and Vicinity.......................................................................................... 8 Figure 2. Soil Map Units ....................................................................................................................... 9 Figure 3. Waters of the United States .................................................................................................. 10 Tables Table 1. Acreage Summary of Waters of the United States ....................................................... 5 Appendices Appendix A Routine Wetland Delineation Data Forms Appendix B Representative Photographs North State Resources, Inc. School Way Bridge Replacement Project February 24, 2011 ii Delineation of Waters of the United States 51175 S ection 1. Summary On behalf of the Mendocino County Department of Transportation (County), North State Resources, Inc. (NSR) conducted a delineation of waters of the United States occurring within the approximately 5.5-acre School Way Bridge Replacement Project site (study area). The study area is located on School Way where it crosses West Fork Russian River in Redwood Valley, Mendocino County, California. The purpose of the project is to replace the School Way Bridge to meet current design standards and to accommodate future traffic volumes. The field delineation was conducted by NSR on July 26, 2010. A total of 0.350 acre of waters of the United States were mapped in the study area. Waters of the United States occurred as intermittent stream (0.342 acre, 346 linear feet) and riparian wetland (0.008 acre). This delineation of waters of the United States is subject to verification by the United States Army Corps of Engineers (Corps). NSR advises all parties to treat the information contained herein as preliminary until the Corps provides written verification of the boundaries of its jurisdiction. S ection 2. Project Location The study area is located within the community of Redwood Valley on School Way at the West Fork Russian River about 10 miles north of the city of Ukiah. It is in the Redwood Valley, California 7.5- minute U.S. Geological Survey (USGS) topographic quadrangle within an unsectioned portion of the Yokaya Land Grant. The center of study area is located at approximately UTM 10 0482061 E, 4346236 N (NAD 83 datum). The location of the study area is shown in Figure 1. The study area includes the following Assessor Parcel Numbers (APN) or portions thereof: 163-131-45 163-131-22 163-131-23 163-131-02 163-131-03 163-131-11 163-131-07 163-131-08 163-131-21 163-131-15-00 163-131-15-70. 2.1 Proximity to Major Highways and Streets To access the study area from U.S. Highway 101 (US-101) take the West Road exit (Exit #557) and travel east approximately 0.1 mile. Turn right at East School Way and travel approximately 0.5 mile to the Redwood Valley Elementary School. Public parking is adjacent to the study area at the playing field on the north side of School Way. 2.2 USGS Hydrologic Unit The study area is located within the Russian USGS Hydrologic Map Unit (Cataloging Unit Number 18010110). The Russian River watershed drains approximately 100 square miles (California Department of Fish and Game 2003). North State Resources, Inc. School Way Bridge Replacement Project February 24, 2011 1 Delineation of Waters of the United States 51175 S ection 3. Environmental Setting 3.1 Current/Recent Land Use The study area is along School Way which is a main two-lane road within the small community of Redwood Valley. There is an elementary school and several private residences adjacent to the study area that is west of the bridge. East of the bridge there is a light industrial area, and the Union Pacific railroad (formerly Northwestern Pacific) crosses School Way. 3.2 Site Topography and Elevation The topography of the study area is generally characterized as a portion of East Fork Russian River channel and the adjacent river valley terraces. The western terrace below the elementary school is steeper than the terrace on the east side of the river. The slope of School Way from the school down to the bridge is approximately eight percent. The bridge deck is at an approximate elevation of 705 feet msl. The river channel is deeply incised, and the western bank is steeper and taller than the eastern bank. The slopes along the western bank exceed 45 degrees (100 percent). All sheet flow along the road and terraces on both sides of the bridge drain towards East Fork Russian River. 3.3 Climate Climate within the study areas is as follows based on historical data collected in Ukiah, California (Western Regional Climate Center 2010): Type: The study area is characterized by a Mediterranean climate with cool, wet winters and hot, dry summers. Precipitation: Precipitation in the study area primarily falls as rain. Average annual rainfall is approximately 37 inches. Air Temperature: Air temperatures in the study area range between an average January high of 57 ºF, and an average July high of 93 ºF. The year-round average high is approximately 74 ºF. Growing Season: The growing season (i.e., 70% probability of air temperature 28 ºF or higher) in