Vantage to Pomona FEIS Index 34 - Laserfiche WebLink

Home Browse Search

Vantage to Pomona Heights Chapter 3 230 kV Transmission Line Project FEIS Affected Environment PAGE 3-279 3.14 WATER RESOURCES As was done in the Draft Environmental Impact Statement (DEIS) and Supplemental Draft Environmental Impact Statement (SDEIS), this section describes the existing conditions (affected environment) and considers issues related to water resources along all Action Alternatives presented in the DEIS and SDEIS, including those raised during scoping. This Final Environmental Impact Statement (FEIS) section consolidates and builds on the information presented in the January 2013 DEIS as well as the January 2015 SDEIS and includes references to those documents throughout the text where appropriate. This FEIS identifies the New Northern Route (NNR) Alternative – Overhead Design Option as the Environmentally Preferred Alternative and has selected the NNR Alternative – Overhead Design Option as the Agency Preferred Alternative. 3.14.1 Data Sources The analysis of water resources in the Vantage to Pomona Heights 230 kilovolt (kV) Transmission Line (Project) area was conducted using planning documents, field studies, and digital data sources. For the purposes of this document, the water resources Project study area is a two-mile wide corridor within which potential impacts resulting from the Project were analyzed. Sources included: • Surface water data from the United States (U.S.) Geological Survey (USGS) National Hydrography Dataset. • Floodplain data for Yakima and Grant Counties from the Federal Emergency Management Agency’s Digital Flood Insurance Rate Map program dated July 22, 2010. Floodplain data for Kittitas County is older Q3 data dated 1996. • National Wetland Inventory (NWI) digital data from the U.S. Fish and Wildlife Service (USFWS). • Digital watershed mapping from the Washington State Department of Ecology (WDOE). • Aerial imagery used in analyzing water resources consists of the National Agriculture Imagery Program (NAIP) imagery, 2009. • Digital Adopted Shoreline data were obtained from the WDOE. • Joint Base Lewis-McChord Yakima Training Center (JBLM YTC) Cultural and Natural Resource Management Plan, January 2002. • FEIS for Fort Lewis Army Growth and Force Structure Realignment, July 2010. • Sage Grouse Habitat Assessment Report for the Project, August 2011. • Special Status Plant Species Survey Report (POWER 2013). 3.14.2 Current Conditions and Trends, Regional Overview 3.14.2.1 Surface Water Precipitation The Project study area is located in south-central Washington generally between the Columbia River and Yakima River in the Central Basin climatological region. The region’s climate is semi-arid, with cold winters and long, hot summers. It is situated in the rain shadow of the Cascade Mountains, with a low level of annual precipitation. Winter snowfall at Priest Rapids Dam and Yakima is 5.9 and 23.5 inches per year, respectively. The total annual precipitation during the period of record for both sites (1946 through 2005) was 7.57 inches. The growing season averages about 150 days. During July and August, it is not unusual for four to six weeks to pass without measurable rainfall. A few damaging hailstorms are reported in the agricultural areas each summer (Western Regional Climate Center 2013).