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2014 -2021 SANTA ANA HOUSING ELEMENT AND PUBLIC SAFETY ELEMENT UPDATES CITY OF SANTA ANA 3. Environmental Analysis g) Place housing within a 100 -year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map? Less Than Significant Impact. The City has two major drainage courses that have the potential for significant flooding: Santiago Creek and the Santa Ana River. However, according to the Federal Emergency Management Agency (FEMA), the City of Santa Ana is located in Zone X, which is any area outside the 1 percent annual chance floodplain (FEMA 2013). Figure 5, Flood Hatiard Map, recreated from the City's Public Safety Element update, also shows that the entire City is outside of the 100 -year flood risk area with the exception of a small portion of the City's western corner. The Public Safety Element update also outlines policies to require future development within the 100 -year flood zone to implement mitigation measures to minimize risks associated with flood hazards. In addition, the City has floodplain management regulations that require new construction or substantial improvements in flood prone areas of the City to be elevated above base flood elevations. Furthermore, potential development as anticipated under the Housing Element would be evaluated on a project -by- project basis and would be required to comply with the City's uniform building codes and regulations as described above. No mitigation measures are necessary. h) Place within a 100 -year flood hazard area strictures which would impede or redirect flood flows? Less Than Significant Impact. See 3.8g above. i) Expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam? Less Than Significant Impact. Santa Ana is located in the Prado Dam, Santiago, and Villa Park Reservoir Inundation Areas. Prado Dam, with a design reservoir capacity of 196,000 acre -feet, is an Army Corps of Engineer earthen facility 21 miles northeast of the City of Santa Ana. The dam is designed and constructed to withstand the maximum probable earthquake for the area, and therefore the probability for dam failure as a result of a seismic event is statistically insignificant. Santiago Dam and Reservoir (Irvine Lake) and Villa Park Dam are a two -pool system west of Black Star Canyon maintained by the County of Orange, approximately seven miles east of the City's border. Santiago Dam is a 25,000 -acre -feet earthen structure retaining Irvine Lake. Downstream is the flood control structure, Villa Park Dam. Santiago Creek, the natural waterway that flows west from the Villa Park- Santiago complex, is in the northern part of the City. System failure would occur when both pools are full and would result in a flood flow path spreading beyond the banks of Santiago Creek. The City of Santa Ana has an Emergency Response Plan that addresses flooding in the event of levee or dam failure. Additionally, any future development would comply with the City's building standards to reduce the risk of structural damage due to flooding. Therefore, the risk from exposure of people and structures to flooding throughout the City due to the adoption of the Housing Element is considered less than significant. No mitigation measures are necessary. Deember 2013 The Planning Center I DC&E • Page 57 75A -79