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Environmental Setting

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Environmental Setting Chapter 2 Environmental Setting Table of Contents 2.1 Introduction ........................................................................................... 2-1 2.2 Land Use ................................................................................................ 2-2 2.2.1 Existing Conditions .......................................................................... 2-2 2.2.2 Land Use Categories ........................................................................ 2-3 2.2.3 Land Use Controls ........................................................................... 2-7 2.2.4 Open Space (Public Lands and Private Easements) ........................ 2-9 2.3 Physical Resources ............................................................................... 2-15 2.3.1 Location ......................................................................................... 2-15 2.3.2 Topography ................................................................................... 2-15 2.3.3 Geology and Soils .......................................................................... 2-16 2.3.4 Climate .......................................................................................... 2-19 2.3.5 Hydrology ...................................................................................... 2-21 2.4 Biological Resources ............................................................................ 2-23 2.4.1 Methods ........................................................................................ 2-23 2.4.2 Biological Diversity in the Study Area ........................................... 2-31 2.4.3 Natural Communities and Land Cover Types ................................ 2-32 2.4.4 Habitat Connectivity and Wildlife Linkages ................................... 2-76 2.1 Introduction This chapter describes the physical and biological resources within the study area that are relevant to the Conservation Strategy. This chapter includes a land use section that provides an overview of the major land use and open space management agencies operating within the study area. The physical resources section provides a characterization of the topography, geology and soils, climate, and hydrology of the study area. The biological resources section includes a discussion of biological diversity, natural communities, land cover types, and focal species in the study area. Together, the land use, physical resources, and biological resources sections provide the necessary context for the biological goals and objectives upon which Chapter 3, “Conservation Strategy,” is based. East Alameda County Conservation Strategy 2-1 October 2010 ICF 00906.08 Chapter 2 Environmental Setting 2.2 Land Use This section examines existing land use conditions and land use plans in east Alameda County. This section provides history and context for land use in the study area; reviews existing land use conditions and relevant land use plans; presents the criteria used to determine land use categories; and discusses significant existing open spaces in the study area and an open space type classification system. 2.2.1 Existing Conditions East Alameda County encompasses 271,485 acres (approximately 424 square miles) and represents 52% of Alameda County, which has a land area of 525,540 acres (approximately 821 square miles). Alameda County is located north of Santa Clara County, west of San Joaquin County, and south of Contra Costa County (see Figure 1-1 for the regional location of the study area). East Alameda County is situated east of the San Leandro Hills and Walpert Ridge (Corbett 2005). The cities of Dublin, Livermore, Pleasanton, a portion of the city of Hayward, and surrounding unincorporated areas are the major developed areas of east Alameda County (Alameda County Community Development Agency 2002). The cities of Dublin, Livermore, and Pleasanton are completely included in the study area. According to the most recent Census data, the population of east Alameda County is approximately 171,652, about 12% of the population of the entire county, which is 1,443,741 (U.S. Census Bureau 2000). In east Alameda County, Livermore has the most residents, with a population of 80,723(City of Livermore 2009); followed by Pleasanton, with a population of 68,755 (City of Pleasanton 2009a); and Dublin, with a population of 46,934 (City of Dublin 2009a). Located between the urban areas surrounding the San Francisco Bay and the Central Valley, east Alameda County has had considerable growth pressure in the recent past. In 1990, the population was approximately 133,000 and will most likely exceed 250,000 by 2010, representing an 88% growth (Alameda County Community Development Agency 2002). The Association of Bay Area Governments (ABAG) has projected that the populations of Livermore, Pleasanton, and Dublin will grow to 89,600; 75,300; and 56,800 by the year 2015, and 95,500; 79,100; and 62,700 by the year 2020, respectively (Association of Bay Area Governments 2006). Dublin was incorporated in 1982 (City of Dublin 2009b), Livermore was incorporated in 1876 (City of Livermore 2009), and Pleasanton was incorporated in 1894 (City of Pleasanton 2009a). Dublin was incorporated to accommodate the increasing demand for commercial and residential development in the area, and has experienced a more recent increase in growth compared to Livermore East Alameda County Conservation Strategy 2-2 October 2010 ICF 00906.08 Chapter 2 Environmental Setting and Pleasanton, which have grown steadily since incorporation (City of Dublin 2009b). Recent growth in the region and the subsequent impacts on residents’ quality of life are major concerns for the region (Alameda County Community Development Agency 2002). The County and Cities of Livermore, Pleasanton, and Dublin maintain a strong commitment to protecting the natural and agricultural resources within and surrounding their respective jurisdictions. Reflecting this vision, the County and Cities of Livermore and Pleasanton have each adopted an Urban Growth Boundary (UGB), while Dublin has adopted Planning Area Boundaries as an ultimate build-out line. More detail on the open space policies and UGBs is provided in Sections 2.2.4 and 2.2.3.1 below for each participating jurisdiction. 2.2.2 Land Use Categories Understanding the current land use patterns and potential future land uses in the study area were an important step in developing the strategy discussed in Chapter 3. This understanding, in conjunction with an assessment of the biological resources in the study area allowed for the development of a conservation strategy that is informed by the current land use patterns in the county. Furthermore, land use designations aid the process by informing agencies as to the areas that are currently protected, areas that are likely to be affected, and areas where conservation will need to occur. The general plans for the cities of Dublin, Livermore, and Pleasanton and Alameda County were used to identify the future extent and location of urban and rural development in the study area. Land use designations vary across jurisdictions and are in many more categories than necessary for conservation planning purposes, so the designations were simplified and standardized. The process by which a land use map was developed and how land use categories for the Conservation Strategy were assigned is described below. 2.2.2.1 Land Use Methodology Land use planning designations for Alameda County and the cities of Dublin, Livermore, and Pleasanton were used to develop a single land use map for the Conservation Strategy. Future land uses were assumed to be consistent with the County’s general and specific plans (East County Area Plan [2002]; South Livermore Valley Area Plan [adopted by Alameda County Board of Supervisors on February 3, 1993]); and the general plans for the City of Dublin [2008], City of Livermore [2004], and the City of Pleasanton [2009b]). The County’s general and specific plans project future land use to 2010, and the Dublin, Livermore, and Pleasanton general plans project future land use to 2025. Using these East Alameda County Conservation Strategy 2-3 October 2010 ICF 00906.08 Chapter 2 Environmental Setting projections for this strategy is appropriate given the strength of each jurisdiction’s commitment to constraining future growth within established UGBs (see Section 2.2.3 below for a discussion of local land use controls). One hundred five land use planning designations from the four land use authorities were aggregated into the following three simplified land use planning categories: Urban/Developed; Private agriculture, and/or Rangelands; and Public Lands. Development of these categories was guided by the nature of the potential activities that will require a discretionary permit within each land use category and their relative impact on biological resources. For example, the many urban land use categories (e.g., commercial, industrial, mixed use) were combined into a single land use category, “Urban/Developed,” because all of the land uses result in similar effects on biological resources. Table 2-1 shows general plan land uses and the land use categories to which they were converted for this strategy. Some land use designations were split into two or more of the land use categories for this strategy. 2.2.2.2 Generalized Land Use Categories Historically, agriculture has played a major role in the economy of Alameda County (Alameda County Community Development Department 2008). Agriculture continues to be an important part of
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