Executive Summary
Introduction. This report presents the results of a case study evaluation of a Maintenance Decision Support System (MDSS) project under a program funded by the U.S. Department of Transportation’s (USDOT) Intelligent Transportation Systems (ITS) Joint Program Office. The Federal Highway Administration (FHWA) Road Weather Management Program (RWMP) has sponsored development of a prototype Maintenance Decision Support System (MDSS). The federal MDSS prototype software modules are available to private vendors who have utilized them to develop decision support applications tailored to the needs of state Departments of Transportation (DOTs). An MDSS was offered to the Scarborough crew of the Maine Department of Transportation (MaineDOT) by Meteorlogix/DTN for use during the winter of 2006-2007 in the region of Portland, ME. The DTN system, known as WeatherSentry, includes MDSS capabilities.
Methodology. The methodology used to assess the benefits and lessons learned associated with the use of an MDSS by the MaineDOT Scarborough crew involved a careful tracking of each of 12 winter storm events that occurred in the study region (a 12-mile segment of interstate in Portland, ME) during the winter of 2006-2007, coupled with reconstruction of the crew’s decision processes and treatment actions throughout each event. MaineDOT records a daily statistical record of labor hours, materials and equipment usage and costs, plus the timing and nature of treatments applied during each storm event. The evaluation team tracked the observed weather conditions recorded for each storm at the Portland Jetport Automated Surface Observing System (ASOS) facility. Also, archived records of the MDSS hourly forecasts and treatment recommendations were tracked throughout the duration of each storm event. Finally, every alert issued by the MDSS, based on parameters selected by the Scarborough crew, were tracked.
A narrative was developed describing each event based on a telephone debriefing with members of the Scarborough crew and supervisor, coupled with an analysis of the available MDSS data and observational data from other sources. The debriefing discussion followed a structured set of questions that were designed to elicit what happened in each event, how the Scarborough crew responded to the event, what information was used to assist the crew in deciding how to respond to the event, and how information provided by the MDSS was accessed and used in the event. In summarizing the assessment of each reconstructed event, the intent was to determine and describe whether and how the MDSS was of benefit and the magnitude of that benefit through better timed and more efficient treatment actions and in terms of lessons learned from the response process that could be of value to other DOTs. A key element in these post-event discussions was to explore with the supervisor and crew how they thought they would have responded in the absence of the MDSS as a way to understand the role and benefit of the MDSS.
Findings and Lessons. Compared with typical winters in Maine, the winter of 2006-2007 was milder and there were fewer severe storm events. For each event, the Scarborough crew sought to include the MDSS in their decision making in ways they thought would be helpful. This first winter with the MDSS provided the crew with an opportunity to experiment with their uses of the MDSS. The experience overall was positive, though the available data were not adequate to support a more quantitative assessment of cost savings from the use of the MDSS. Nevertheless, MaineDOT personnel said they benefited from this first season with the MDSS in a number of more qualitative ways. The following are findings from this experience:
- The MDSS offers valuable training and learning opportunities for the crew. State DOT road maintenance supervisors and crews are highly experienced and skilled at their winter road maintenance jobs, but they generally lack experience with new computer-based support technologies and are often skeptical of the benefits such technologies offer. The Maine management and crews found this first season with the MDSS provided them with a valuable training experience. DOT managers saw this as a needed first step toward integrating route-specific weather and pavement condition information along with region-wide National Weather Service (NWS) forecasts on a Geographic Information System (GIS) platform. It offered the crews an opportunity to experiment with the new technology with the training and support of the MDSS vendor.
- The full potential of MDSS is yet to be realized. To gain the most benefit from an MDSS requires time to understand the various “pathways to benefits” by which an MDSS, through road weather forecasts and pavement treatment recommendations, can guide maintenance crews to more efficient and cost-effective operations. The learning and acceptance process takes time, and expectations need to be managed accordingly. MaineDOT views the MDSS as offering an effective training environment to help raise the bar for all their statewide crews.
- An MDSS offers an important new tool in a maintenance toolbox. Many of the core capabilities of an MDSS have not previously been available to DOTs. These include pavement temperature and bridge frost forecasts, ready access to historical trends, more precise location-specific weather forecasts, locally tuned pavement treatment recommendations, and helpful alerts to support more effective decision making. A key benefit to MaineDOT was the availability in the MDSS of an integrated platform for weather forecast display and analysis statewide. Thus, it supplemented not only their traditional maintenance support tools, such as other weather forecasting services or crew observations and experienced judgment, but also added new value and tied all this together into a well-integrated decision support system.
- MDSS forecast accuracy and consistency help build trust. An MDSS provides a tool intended to yield high quality, timely weather forecasts at a much more granular level than is typical of current DOT practice, including route-specific forecasts. If it can do this well and consistently, then it will fill a niche capability not offered by the more traditional regional weather forecast services. The circumstances encountered in Maine during the winter of 2006-2007 were particularly challenging because of maritime climate effects in the Portland area and temperatures close to freezing in most of the storm events. The MDSS was reasonably effective in forecasting storm timing but it was especially difficult to forecast precipitation type and amounts. An MDSS can benefit from the availability of good observational data along the corridors subject to forecasts as a way to fine tune those forecasts.
- Treatment recommendations in an MDSS need to be fine-tuned to reflect unique local treatment practices and microclimates. State DOTs need to work closely with the MDSS vendor to develop customized treatment recommendations that incorporate local conditions and crew practices as well as national and state best maintenance practices. In the case of MaineDOT, the statewide average treatment recommendations that were incorporated into the MDSS were frequently seen as offering inadequate material amounts for the road conditions encountered in the Portland area. Since the MDSS treatment recommendations were infrequently followed, it was not possible to evaluate their efficacy during this evaluation period. This experience emphasizes the importance of configuring the MDSS with a treatment regime that is seen as appropriate by the local crews and that they are willing to implement consistently.
- MDSS provides a new way of looking at treatment decisions. By understanding the context and utility of previously unavailable information, such as road temperature trends and bridge frost forecasts, maintenance crews can improve their decision making on how best to treat their roads. For example, road temperature trends provided to MaineDOT by the MDSS were useful as crews planned their treatments. With the MDSS providing a wealth of data, training the supervisors and the crew in accessing and utilizing these new features provided by an MDSS is critical.
- Communicating MDSS recommendations and forward correction are critical to optimal MDSS performance during storm events. Crews need effective ways to access the MDSS recommendations during a storm event. Similarly, the MDSS needs to be updated with the latest field reports on road conditions and treatments performed. Maintenance supervisors and crews typically find themselves consumed with the tasks of “fighting the storm” and feel they have no time to stay connected with the MDSS. Under these conditions, they are more prone to rely on their experiences and judgment than to take the time to access and follow the MDSS recommendations.
Conclusions. The MDSS deployed by MaineDOT in the winter of 2006-2007 offered the DOT and the Scarborough road maintenance crew a useful winter storm planning tool. In its current configuration, it is primarily a weather forecasting tool. The needs of state DOT’s vary widely, and many that have not yet decided to deploy an MDSS may want to move is this direction in a more step-wise fashion without committing to a costly, fully evolved MDSS system initially. There is benefit in offering a relatively inexpensive tool focused on helping maintenance operators better forecast the timing and type of precipitation at the beginning of a storm event.
The MDSS offered a tool that helped MaineDOT integrate a variety of critical weather data into a useful GIS platform. These capabilities alone meet the most frequently expressed needs of DOTs that want a tool that can help them better time their pre-treatment decisions and determine the correct materials for the conditions they are going to face at the front end of a storm. DOTs want to know start time, precipitation type, anticipated amount of precipitation, and duration. An MDSS that could improve a DOT’s ability to only do that would be very valuable, and may be all that some state DOTs want or need.
The transportation community, including federal and state agencies, should continue to support the development of several different MDSS systems that offer state DOTs a choice of capabilities, functionality, and cost. This kind of environment helps encourage innovation and attention to meeting a range of different needs in different parts of the country. The MDSS deployed by MaineDOT raised awareness throughout the state of the value and potential of a tool that could supplement their existing weather forecasting and management tools with a set of capabilities they didn’t have previously. Transportation agencies also can support training to capitalize on this growing awareness and encourage the further development and wider use of MDSS tools to help improve overall transportation safety, mobility, and productivity.