R&H Integration Back Dating process - Minnesota DOT

Discussion created by jessepearson on Apr 25, 2019

Greetings R&H community!

I wanted to send this out to the Roads & Highways DOT community because I mentioned that I would on the March RHUG call.  Here is a little background on our Crash Integration project with our Traffic Safety Office and the Department of Public Services (DPS): 

The main requirements of this project are as follows:

  • 3.3 million crashes need to be updated against the existing roadway (LRS network).
  • Historical crashes need to be reported on the roadway including crashes retired due to alignment changes.  
  • The crashes in the field are based on a roadway network that could be 6 months to a year out of date so these crashes will need to be brought up to the current LRS network.
  • There was also a need to make edits to the spatial location and/or attributes of a crash year-round. 


We had a discussion with Clive Reece from ESRI of the following technical solution who verified that our back-dating process was sound and would work fine.

1. Load the crash data as an external event

2. Run the Relocate events function on the external event. The function will run the external event of the LRS changes and if a change occurred, the most recent route and measure will be returned. If the LRS was not updated where the event is located, then nothing is returned. 

3. We have broken down the relocate event results into  2 datasets that need to be dealt with separately. The first dataset includes events that ran through the Relocate events function and had "no error" in the LocError field. It also includes the crashes where nothing is returned after running Relocate events function.  The second dataset has all the crashes that has "Route Not Found" or "Route Location Not Found". These are what we are calling 'No-Plots', and they will have to be dealt with separately.

4. For the 1st dataset of corrected data we will append into an internal event where the history will be brought as well. After the corrected crashes gets into an internal event the LRS will be then automatically keep the crashes up to date with new roadway changes. 

5. For the 'No-Plots' we have to deal with these in a manual fashion and bring them into the internal event when they are corrected.


Take a look at our 10,000' view diagram for our Crash Integration back-dating process.


Feel free to reach out to me if you have questions or if you are going through this right now.  We are also building an automated back-dating integration process but this post is already too long  .


Jesse Pearson

LRS Integration Portfolio Manager

Minnesota Department of Transportation

PH: 651-366-3881