WFRC Safety Action Plan Supplemental Information
Case Study Project Locations and Safety Analysis
Description
This Story Map is a visual tool that supplements the WFRC Comprehensive Safety Action Plan (CSAP) Final Report. The tool includes:
- Safety analysis results - segments and intersections identified by the safety sub analyses completed as part of the CSAP.
- Case Study Projects locations - locations (segments and intersections) for which Case Study Project Information Sheets were prepared.
For detailed information on the safety analysis methodologies, project identification, and safety countermeasure recommendations, please refer to https://wfrc.org/programs/csap/
CSAP Study Area
The CSAP study area includes each jurisdiction within the WFRC region, as illustrated in Map 1. To organize the large number of jurisdictions within the WFRC region into manageable analysis areas, jurisdictions are grouped into Geographic Focus Area (GFA). Map 1 below shows the GFA boundaries and associated jurisdictions.
All the maps included in this Story Map can be expanded for a full page view (upper right) and navigated using the following tools:
- Search for a specific area or jurisdiction (upper left)
- The Legend will provide a key for all visible map elements (lower left)
- Zoom and Home buttons in the lower right can be used to get a more detailed look at the map or return to the center of the study area
- Click on any elements of interest and a pop up window will display relevant information
- Ex: Clicking within a jurisdictions boundary will reveal its associated GFA, i.e. Layton is in the South Davis County GFA
Map 1 - WFRC CSAP Study Area
Case Study Project Locations
As described in the CSAP Final Report, Case Study Project Information Sheets were prepared for up to three locations within each jurisdiction in the WFRC region. Case Study Project Information Sheets, available in the CSAP Final Report, include location, historic crash data, and recommended safety countermeasures with estimated costs.
Project Information Sheets are included in the CSAP Final Report Appendix D. A separate section of Appendix D is prepared for each of the 1 Geographic Focus Areas (GFAs).
Map 2 depicts Case Study Project Locations. Please follow these steps to access the Case Study Project Information Sheets prepared for each jurisdiction:
- Click on the Case Study Project of interest
- A pop up window will appear with the roadway/intersection name
- Note the Appendix D Number listed to locate the Case Study Project Information Sheet
- Note the Project ID that can be matched to a Map ID on the Case Study Project Information Sheet.
- Complete Safety Analysis maps show all roadway/intersection identified as a safety need in the CSAP. Safety improvement projects can be developed for any of the identified locations. The Safety Analysis section details each step followed to identify the Case study Project locations.
Map 2 - Case Study Project Locations
CSAP Safety Analysis
Case Study Project Locations were identified from several safety sub analyses that were completed. Results of each of these analyses are illustrated in the following maps. A description of the safety analysis methodology is also provided alongside each map.
Each safety sub analysis focused on a different safety element to identify the roadways and intersections with the highest potential for safety improvements. While reviewing the maps below, each methodology will be layered on top of one another to enable a display of each safety sub analysis.
For a comprehensive explanation of the safety analysis methodologies, refer to Chapter 5 of the WFRC CSAP Final Report.
Map 3 - Critical Crash Rate Analysis
The Critical Crash Rate (CCR) analysis compares the observed crash rate of a location to the expected crash rate based on similar locations with similar traffic volumes. Each GFA was analyzed individually to calculate CCRs specific to the GFAs demographics and facilities.
A location with a positive CCR indicates higher-than-expected crashes rates and a potential for safety improvement. The higher the CCR value, the larger the potential to improve safety at that location.
Map 3 (at right) illustrates segments and intersections with a potential for safety improvement based on the CCR analysis.
The following scale can be used to broadly interpret the potential for safety improvements:
- 0 - 0.5 Low Safety Need
- 0.5 - 1 Moderate
- 1 - 3 High
- ≥ 3 Extremely High Safety Need
Map 4 - Crash Profile Risk Assessment
The Crash Profile Risk Assessment reviewed fatal and serious injury crashes reported in the WFRC study area to identify attributes that correspond to a higher frequency of fatal and serious injury crashes.
Characteristics Considered:
- Traffic volumes
- Speeds
- Roadway Types
- Lighting
- Access Density
- Etc.
The Crash Profile Risk Score Map 4, has a maximum value of 30 points, and any segment with a score of 20 or higher is a candidate for safety improvements.
Map 5 - usRAP Rating Assessment
The United States Road Assessment Program (usRAP) is a proactive tool for analyzing the safety of a roadway.
Star ratings are assigned to each segment of the roadway network. Star ratings consider road infrastructure attributes known to impact the likelihood of a crash and its severity. The roadway’s star rating is based on the presence or absence of these design and traffic control features.
5 star roadways have the most safety-related design and traffic control features. 1 star roadways have the fewest safety-related design and traffic operational features.
The roadways highlighted in Map 5 at right have a star rating of 1 or 2 in the vehicle, pedestrian, or bicyclist category of usRAP ratings.
Map 6 - Local Street Assessment
A Local Street Risk Assessment was performed on all segments that are not a state route or a federal-aid route within the WFRC study area. This assessment integrated available collision data and other factors into a scoring system appropriate for local roads, given that usRAP data was not available for local roads. These location factors included:
- Active transportation activity
- Equity focus areas (see Map 8 for more information)
- Speed-related data
The scoring process identified local streets that have both the highest rate of actual collisions along with land use and locational characteristics that indicate a high level of vulnerable users. Roadway segment scores were then stratified to identify the 5% of local streets in the WFRC study area with the highest scores (indicating high risk). The highest-scoring local streets became the Regional Top 5% Local Street Segments.
The GFA Top 10 Local Street Segments is a combination of high scoring roadway segments respective to each GFA and the Regional Top 5% Local Street Segments. Connected Top 5% segments were used to identity potential project corridors to be included in the Composite Network.
Map 7 - High Risk Safety Network
Informed by each of the safety analyses previously described, a Composite Score was calculated to identify roadways and intersections with the highest potential for safety improvements.
Map 8 - Equity Areas
To inform prioritization of safety improvements and identify the equity priority communities within the WFRC region, a locally defined equity priority index was developed. The index provides insight on whether transportation-disadvantaged people are present in a place and the degree to which they are experiencing transportation challenges. It also assesses which focus on the concentration of low-income households and individuals identifying as members of racial and ethnic minority groups.
In the map to the right. Map 8, the red shaded census tracts indicate the highest priority equity areas, orange the next highest, and yellow as the least priority equity areas.
Use the map slider to view the all the identified roadways and intersections with and without their associated equity areas.
Map 9 - All Safety Analysis Results
Map 9 illustrates all the safety analyses results previously shown. All the roadways and intersections displayed in Map 9 have an identified safety need.