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Risk Assessment Methodology  Earthquake—A Level 2 analysis was performed to assess earthquake exposure and vulnerability for four scenario events and one probabilistic event:  A Magnitude-6.93 event on the Butano Fault with an epicenter 17.5 miles south of Redwood City  A Magnitude-7.14 event on the Monte Vista Shannon Fault with an epicenter 16 miles south- southeast of Redwood City  A Magnitude-7.38 event on the San Andreas Fault with an epicenter 4 miles west of Belmont  A Magnitude-7.44 event on the San Gregorio Fault with an epicenter 4 miles south of Half Moon Bay  The standard Hazus 100-year probabilistic event Sea Level Rise, Landslide/Mass Movements, Severe Weather, and Wildfire Historical datasets were not adequate to model future losses for these hazards of concern. However, areas and inventory susceptible to some of the hazards of concern were mapped by other means to evaluate exposure. A qualitative analysis was conducted for other hazards using the best available data and professional judgment. Drought The risk assessment methodologies used for this update focus on damage to structures. Because drought does not impact structures, the risk assessment for this hazard was more limited and qualitative than the assessment for the other hazards of concern. 7.3 SOURCES OF DATA USED IN MODELING AND EXPOSURE ANALYSES 7.3.1 Building and Cost Data Replacement cost is the cost to replace the entire structure with one of equal quality and utility. Replacement cost is based on industry-standard cost-estimation models published in the 2020 edition of RS Means Square Foot Costs. It is calculated using the RS Means square foot cost for a structure, which is based on the Hazus occupancy class (i.e., multi-family residential or commercial retail trade), multiplied by the square footage of the structure. The construction class and number of stories for single-family residential structures also factor into determining the square foot costs. Replacement cost values and detailed structure information derived from parcel and building footprint data were loaded into Hazus. When available, an updated inventory was used in place of the Hazus defaults for critical facilities and infrastructure. 7.3.2 Hazus Data Inputs The following hazard datasets were used for the Hazus Level 2 analysis conducted for the risk assessment:  Flood—The effective Digital Flood Insurance Rate Map (DFIRM) for the planning area was used to delineate flood hazard areas and estimate potential losses from the FEMA 1-percent-annual chance and 0.2-percent-annual-chance (100- and 500-year) flood events. Using the DFIRM floodplain boundaries and base flood (1-percent-annual chance flood) elevation information, and the County’s 5-foot digital elevation model data, flood depth grids were generated and integrated into the Hazus model.  Dam Failure—Dam failure inundation area boundaries and depth grids for were provided by the California Department of Water Resources for 13 dams: Bear Gulch, Coastways, Crocker, Emerald Lake 1 Lower, Felt Lake, Laurel Creek, Lower Crystal Springs, Notre Dame, Pilarcitos, Pomponio 7-5