Integration of Pikalert® into the Wyoming CV Pilots Will Save Lives and Reduce Delay

A major component of the Connected Vehicle Pilot being deployed by the Wyoming Department of Transportation (WYDOT) is the Pikalert® system for real-time alerts and advisories and other actions related to road weather conditions.  Road weather is a significant concern for the 402-mile stretch of Interstate I-80 across Wyoming, where winter snowstorms and windstorms frequently create conditions that result in multi-vehicle collisions.  In addition to the personal injury and property damage caused by these collisions, the incident response may close the highway for hours or more than a day.  From October 2015 to September 2016, there were more than 1,600 crashes on I-80, resulting in 18 fatalities and 271 injuries. During this same time, roads were closed to all vehicles for over 1,500 hours.  

One of the key goals of the WYDOT CV Pilot deployment is to reduce the frequency of weather-related incidents by collecting and processing road weather data to issue warnings and alerts by various communication media, and to manage the highway by issuing variable speed limits for specific highway segments or closing them.  The Pikalert program has transitioned from a research project to a vital component of this statewide Pilot program. To ensure Pikalert’s success, WYDOT is currently evaluating the consistency of the Pikalert forecasts with plans to tweak the system for known micro-climate issues.

The Pikalert system is a product of the National Center for Atmospheric Research (NCAR), sponsored in part by the Road Weather Management program of the U.S. Department of Transportation (USDOT) Federal Highway Administration (FWHA).  Pikalert collects weather observations from stationary Environmental Sensor Stations (ESS) and from 50 instrumented state maintenance vehicles including snowplows that automatically report on road conditions.  Some related values such as air temperature and windshield wiper status will be collected by the WYDOT CV Pilot system.

Pikalert performs quality checks on the received data by comparing the data values to previous values, current ancillary values reported by other sources, and to established models of weather behavior.  Validated data values are then aggregated by time (every five minutes) and location (in 5-mile segments) and input to a Road Weather Hazard (RWH) module, which contains algorithms for weather prediction.  For example, the RWH module uses precipitation, humidity, temperature, and elevation values to predict the likelihood of snow or fog by highway segment.

Given current “nowcast” and forecast weather conditions, a CV application in the Wyoming Traffic Management Center (TMC) in Cheyenne may determine to send Spot Weather Impact Warnings and/or speed recommendations via Dedicated Short Range Communications (DSRC) to connected vehicles on the highway, including long-distance truck fleets and state maintenance vehicles, tailored for their locations.  Variable speed limits may be changed along four segments of the highway.  Warnings may be disseminated to non-connected vehicles by other means, including the Wyoming Traveler Information (WTI) interface which updates the 511 systems (web, phone, and email/text messages) in near real time, highway advisory radio, variable message signs, satellite communications to satellite-enable connected vehicles, and the Commercial Vehicle Operator Portal (CVOP), which has over 800 commercial subscribers.

In addition, WYDOT may close segments of I-80.  Advance notification of highway segment closures will enable drivers to make plans for alternate routes or for stopping to wait out the storm at a more convenient parking area.
Pikalert began in 2011 as the “Vehicle Data Translator” project, sponsored by NCAR and the FHWA Road Weather program.  The project tested the ability to receive, validate, and integrate road weather observations in real-time and use them for predictions of road weather conditions.  It was used in the “Integrated Mobile Observation” test programs in Minnesota, Michigan, and Nevada to collect weather information from connected state maintenance vehicles.  The inclusion of Pikalert in the WYDOT CV Pilot project moves the program from research status to large-scale deployment. 
The data collected by Pikalert will also be transmitted to the Connected Vehicle Program Evaluation Platform (CVPEP) to be used by the CV Pilot program evaluation teams (Volpe National Laboratory and Texas Transportation Institute), and to the USDOT ITS DataHub so the data can be used by all interested researchers.  The data is also transmitted to the USDOT Situation Data Warehouse (SDW) to enable future research. 

The base Pikalert software (Version 5.0) is open source, and is available on USDOT’s ITS CodeHub.  The Pikalert system is available at no cost to other CV deployers though agencies planning to deploy it must anticipate some costs associated with system setup and integration. Wyoming’s enhancement of the Pikalert software will be available on USDOT Git server when its development is complete.  Users of the software who make enhancements to the code are invited to contribute the modifications to the user community.