APPENDICES - Laserfiche WebLink

The Wildland Urban Interface in Pleasanton Location and Extent of the WUI The Wildland Urban Interface (WUI) is the geographical area where structures and other developments meet or intermix with wildlands or areas of unmanned vegetative fuels (ICC, 2021). Within the City of Pleasanton, there are two WUI areas. First are the hillside areas on the west side of the city below Pleasanton Ridge. This area extends along the entire west side of the City, covering the entire hillside west of Foothill Road to the city limits near the ridgeline. The second area is on the hillside along the City's south side, extending from I-680 east to State Route 84. Both areas are characterized by low-density development abutting or intermixing with large areas of continuous, unmanaged natural vegetation. Both areas contain hilly terrain. However, the first area along the Pleasanton Ridge is characterized by a steep, generally east-facing large slope from the valley bottom to the ridgeline. In contrast, the second area along the city's south side is characterized by numerous hills and small ridgelines. The State (CAL FIRE) has created Fire Hazard Severity Zone Maps (FHSZ) that designate and identify areas where there is a higher wildfire hazard. The city has adopted the state’s recommendations for the FHSZ boundaries within the city limits. For the purposes of this wildfire section, the WUI areas in the city have the same boundaries as the CAL FIRE FHSZ’s in the city. Wildfire knows no boundaries, and this is true for the lands surrounding the City. The WUI areas within the City boundaries are not isolated islands surrounded by urban areas. Rather, they are continuations of large WUI and wildland areas that extend further west into Pleasanton Ridge Park and south into hills surrounding the San Antonio Reservoir. Figure 1 shows the CAL FIRE Fire Hazard Severity Zone maps for the City and the surrounding area. The areas colored in yellow, orange, and red are the FHSZs and WUI areas. As shown on the map, the State has different designations for portions of the FHSZ and WUI areas. First, the FHSZ classifies areas as either State Responsibility Areas (SRA) or Local Responsibility Areas (LRA). These classifications refer to who has the primary responsibility for the suppression of wildfire; on SRA lands, the state is responsible (e.g., CAL FIRE), and on LRA lands, the local agency is responsible (e.g., LPFD). Next, the FHSZ classifies SRA areas as having Moderate, High, or Very High fire hazard severity, while LRA areas are only classified as having Very High fire hazard severity. For the purposes of this wildfire section, the specific classifications is not important. Instead, it is more important to identify the areas that are within a FHSZ and WUI area. 6