Alberta RWIS Network Expansion, Winter Risk Assessment and Priority List for Advanced Winter Maintenance Strategies

In 2003, Alberta Transportation (AT) completed an Advanced Traveller Information System (ATIS) and Advanced Transportation Management System (ATMS) Blueprint project. Part of this project was to determine where Road Weather Information Systems (RWIS) sites should be located on the National Highway System (NHS) to provide the optimal coverage. After deployments it was recognized that coverage solely on the NHS resulted in gaps in the real-time and forecast road condition information throughout the province. These gaps prompted a challenge to AT to respond in a proactive, timely manner to the weather events. The deployment has been a resounding success with the public. Existing road condition and atmospheric forecast is currently readily available through the province’s current ATIS service provider. The increased public access and availability of this information has meant increased pressure on AT to expand the RWIS service to areas previously not covered in the first phase deployment. In 2008, AT undertook an RWIS expansion study to identify the gaps and determine which technology would best provide the relevant road weather information necessary to support winter maintenance activities. The expected outcome of this project is a consistent coverage across the province which will redefine current maintenance levels on a regional basis, reduce priority based maintenance activities, and help in the continued provision of a consistent level of service. AT recognizes their limitations with respect to the level of maintenance that can be economically provided for the majority of the road network. AT also recognizes there are segments which have been identified as being at a higher winter collision risk. Rather than increasing the level of service (across the board) to accommodate these areas, the province has taken the approach of providing advanced winter maintenance practices at specific locations. Having embarked on this tiered approach to maintenance levels of service, AT has been inundated with requests to install advanced winter maintenance technology. The 2008 study employed the GIS winter road condition model used for locating the original RWIS sites, reviewed collision statistics, and developed algorithms to allow network-wide assessment of winter driving risks. Based on the relative ranking of the risk and a short list of winter risk mitigation strategies, AT was provided with a relative ranking and priority list for deployment of advanced winter maintenance technologies. This paper will discuss the regional and micro level RWIS assessments that were completed. It will also review the risk assessment which identified the locations with a high winter collision risk. Finally, the paper will overview the resulting deployment plan which recommended approximately 20 RWIS sites on the provincial highway system.