Saticoy & Wells Community Plan & Development ... - City Of Ventura

Saticoy & Wells Community Plan and Code EIRSection 4.8 Hydrology and Water Quality4.8.2 Impact Analysisa. Methodology and Significance Thresholds. This evaluation is based on a review ofexisting information that has been developed for the Project and other available regionalsources. Impacts would be considered significant if development facilitated by the Projectthrough the year 2025 would:• Violate any water quality standards or waste discharge requirements• Substantially alter existing drainage patterns such that substantial erosion wouldoccur on- or off-site• Substantially alter existing drainage patterns such that flooding would occur on- oroff-site• Create or contribute runoff water that would exceed the capacity of existing orplanned stormwater drainage systems or provide substantial additional sources ofpolluted runoff• Place housing within a 100-year flood hazard area• Place within a 100-year flood hazard area structures that would impede or redirectflood flows• Expose people or structures to risk of flooding, including as a result of dam failureSince the Project Area lies more than seven miles from the Pacific Ocean, impacts related toflooding due to seiches and tsunamis, are less than significant. Therefore, these impacts are notanalyzed.b. Project Impacts and Mitigation Measures.Impact HYD-1 Development facilitated by the Project could place newdevelopment within 100-year flood zones and dam inundationzones. However, compliance with the City Flood PlainOrdinance, 2005 General Plan actions, and proposedCommunity Plan actions would reduce impacts to a Class III,less than significant, level.The primary effect of flooding, where urban encroachment on flood plains has occurred, is thethreat to life and property. Floods may also create health and safety hazards and disruption ofvital public services. Economic costs may include a variety of flood relief expenses, as well asinvestment in flood control facilities to protect endangered development. The extent of damagecaused by any flood depends on the topography of the area flooded; depth, duration, andvelocity of floodwaters; the extent of development in the floodplain; and the effectiveness offorecasting, warnings, and emergency operations. Encroachment onto floodplains, such asartificial fills and structures, reduces the capacity of the flood plain and increases the height offloodwater upstream of the obstructions. The 2005 General Plan includes the following actionsrelating to flood hazards:Action 7.7Require project proponents to perform geotechnical evaluations andimplement mitigation prior to development of any site:4.8-6City of Ventura