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Santa Ana Safe Mobility Plan I Revised Scope of Work City of Santa Ana, CA This systemic analysis will provide the basis for long term project development, as roadway elements that have been over -represented in collisions can be gradually phased out of the Santa Ana landscape, and replaced with facilities that protect people who walk, bicycle, or drive from making decisions that might cause a crash. 4.3 Hot Spot Analysis We will conduct a hot spot analysis to identify high crash corridors and locations (intersections and mid -block) throughout the city. A raster based GIS analysis which places a small buffer around each collision and displays a darker color as more collisions overlap allows for an effective visualization of crashes at particular intersections and at the corridor level. We will create a summary table of high crash locations and corridors, with the location name, number of collisions and fatalities, as well as a series of columns to identify each risk factor present (from the risk analysis above) to inform the selection of appropriate countermeasures in Task 6. Many of these locations are likely to rise to the top as locations to be reviewed as part of Task 5, which will allow us to compare the risk factors with field observations and community feedback on conditions and behaviors. 4.4 Preliminary Menu of Countermeasures We will introduce a list of potential countermeasures for staff consideration and feedback prior to developing the recommended countermeasures at individual locations in Task 6. Several resources provide an up to date and comprehensive list of countermeasures. The concluding section of our collision analysis report will identify the subset of countermeasures (including engineering, enforcement and education activities) that apply to collision types identified in Santa Ana. This task provides the opportunity for Santa Ana and other agencies involved in street design to provide feedback on a variety of published design guides, including the National Association of City Transportation Officials (NACTO) guides for urban street design and bikeways. Example resources we will draw from include: • PEDSAFE Pedestrian Safety Guide and Countermeasure Selection System (FHWA) • BIKESAFE Bicycle Safety Guide and Countermeasure Selection System (FHWA) • Proven Safety Countermeasures (FHWA Office of Safety) • Highway Safety Manual and Crash Modification Clearinghouse • NACTO Urban Street Design Guide • NACTO Urban Bikeway Design Guide Deliverables: Draft and final Santa Ana Collision Analysis Report which will include a citywide analysis, systemic risk analysis, hotspot analysis, and preliminary menu of countermeasures. Assumptions and/ or exclusions to the scope of work • We suggest the collision analysis include a risk-based approach to identify patterns and possible over -representation of crash types based on attributes of the roadway network, in order to develop a proactive response to conditions associated with collisions. • Our experience with walling and biking collision analysis suggests that a to -year timeframe maybe desirable, as sample size can be an issue. NelsonlNygaard Consulting Associates, Inc. 15