Configure Traffic Crash Analysis

Traffic Crash Analysis can be used to analyze crash data and identify streets and intersections where concentrations of serious and fatal crashes occur.

In this topic, you will learn how to configure the Traffic Crash Analysis solution to meet specific needs in your organization.

Load traffic crashes

The Fatal and Serious Injury Dashboard can be used to share locations of traffic crashes that resulted in serious injury or fatality to motorists, cyclists, or pedestrians. The dashboard also provides insights into the times of day, days of week, and months of year when these crashes occur more frequently.

Load traffic crashes from a spreadsheet

To load traffic crashes from a spreadsheet, complete the following steps:

1. Sign in to your ArcGIS organization and browse to the TrafficCrashesSource item.
2. From the item page, click Download.
3. Open the CSV file and edit it with your information.

   Note:

   The crash_date field should be formatted with times expressed using a 24-hour clock: 12/31/2020 22:30:00.

4. Save and close the file.
5. In your ArcGIS organization, browse to the TrafficCrashes feature layer.
6. Browse to the feature layer that you want to populate.
7. From the item page, click Update Data.
8. Follow the steps in the Update data wizard to load your data.

Tip:

For more information about uploading data, see Manage hosted feature layers—Append data to layers.

Update crash date, month, day, and hour attributes

When dates are loaded into hosted feature layers, it is assumed the dates are in Coordinated Universal Time (UTC). Those times are then displayed in the local time of the browser, which can cause them to be offset from the original time of the crash. This can be resolved in the attributes by calculating the offset. In addition, the Day, Month, and Hour fields used in the Fatal and Serious Injury Dashboard charts can be calculated from the crash date.

To update the Crash Date, Day, Month, and Hour fields, complete the following steps:

1. Verify that you are signed in to your ArcGIS organization and browse to the TrafficCrashes feature layer.
2. Open the item page and click the Data tab.
3. If you need to offset the crash time to account for UTC, complete the steps below; otherwise, skip to step 9.
4. Click the Date of Crash column.
5. Click Calculate.
6. On the Calculate Field dialog box, choose Arcade.
7. Enter the following expression: ToUTC($feature.crash_date).
8. Click OK.
9. Click the Day column.
10. Click Calculate.
11. On the Calculate Field dialog box, choose Arcade.
12. Enter the following expression: Weekday($feature.crash_date).
13. Click OK.
14. Click the Month column.
15. Click Calculate.
16. On the Calculate Field dialog box, choose Arcade.
17. Enter the following expression: Month($feature.crash_date) + 1.

    Note:

    In Arcade, January is returned as 0 and December is 11. You are adding it to express the months as 1-12.

18. Click OK.
19. Click the Hour column.
20. Click Calculate.
21. On the Calculate Field dialog box, choose Arcade.
22. Enter the following expression: Hour($feature.crash_date).
23. Click OK.

Tip:

For more information, see Calculate field values.

Load high injury network

A high percentage of serious injury and fatal crashes involving motorists, cyclists, and pedestrians often occur on a small percentage of streets and intersections. These streets and intersections are often referred to as the High Injury Network (HIN). The Crash Analysis ArcGIS Pro project can be used to analyze crash data along the transportation network to the streets and intersections that have the highest frequency of crashes. The results of this analysis can be loaded into the High Injury Network Locator and be shared with the public and other stakeholders.

To load your High Injury Network, complete the following steps:

1. Verify that you are signed in to your ArcGIS organization and browse to the Crash Analysis Desktop Application Template.
2. Open the item page and click Download.
3. Unzip and open the Crash Analysis ArcGIS Pro project.
4. On the View tab, in the Windows group, click CatalogPane.
5. In the Catalog pane, expand the Tasks folder, and double-click the Crash Analysis task.
6. In the Tasks pane, click the How to Use Crash Analysis task group to expand the collection of tasks.
7. Double-click the Analyze crashes with FHWA network screening task and follow the steps provided.

usRAP data prerequisites

The United States Road Assessment Program (usRAP) protocol defines how roads should be segmented to analyze risk. Road networks are divided into segments with breakpoints at locations where the following things occur:

• A route begins or ends.
• The county name changes.
• There is discontinuity in the route, such as a gap in mileposts.
• The roadway type changes.
• The annual average daily traffic (AADT) changes by 20 percent or more.
• The speed limit category changes.

The usRAP tools use a series of input feature classes and fields on those feature classes to create basic road segments. Verify your data meets the tools parameter requirements below before using the usRAP tools.

Feature class	Description	Required fields
CrashLocations	Locations of crashes.	crashyear: The 4-digit year the crash occurred, for example, 2020. routename: The name of the route on which the crash occurred.
Routes	Baseline routes.	routename: Name of the route. routetype: Type of the route.
CountyBoundary	County features.	countyname: Name of the county.
AccessControl	Road segments with access control information.	accesscontrol: Type of access control to segment. This field should have a domain applied with the following options: Full Access Control Partial Access Control No Access Control
Medians	Road segments with median information.	mediantype: Type of median of the segment. This field should have a domain applied with the following options: Undivided Roadway Divided Roadway
TravelLanes	Road segments with number of travel lanes.	totallanes: Number of lanes for the segment.
AreaType	Road segments with the type of area.	areatype: Type of area for the segment. This field should have a domain applied with the following options: Urban Rural
SpeedLimit	Road segments with the speed limit.	speedlimit: The speed limit of the segment.
AADT	Road segments with the annual average daily traffic (AADT) values. Each year should be stored as a separate feature class (for example, AADT_2020) and you can include up to five years in the analysis.	aadt: The annual average daily traffic of the segment.