Computer technology has redefined “smart” in America — from smart cards with computer chips to smart growth. At the same time, technology has been revolutionizing a basic public works operation: snowfighting. For example, new snowfighting technologies have been used to enhance spreader controls, plow configurations and computerized routing for many years. However, recent technological advances have introduced a new era of winter maintenance through road weather information systems (RWIS), geographic information systems (GIS) and maintenance decision support systems (MDSS).

Smart snowfighting emerged when managers recognized that pavement, not ambient temperature, is the most important variable to consider when devising snow and ice removal strategies and tactics. Using real-time pavement conditions relayed by RWIS can fine-tune their responses.

An RWIS is a network of embedded roadway sensors with communications links to a central storm command center. There, snowfighting managers determine the magnitude of the storm by using pavement temperature readouts as well as traffic camera feeds and traditional forecasts. Some operations also use mobile infrared pavement monitors, either handheld or vehicle mounted, while others subscribe to enhanced weather services and integrate the data sent from their RWIS sensors. Roadway friction measures also help fight winter road problems. Today, state departments of transportation (DOT) are operating 2,214 environmental sensor stations, according to the Federal Highway Administration (FHWA).

Once the snowfighting strategy has been determined using a RWIS system, trucks and other vehicles sent into the field are tracked using GPS. Not only will command center supervisors know the location of each truck at any time, GPS can tell if the operator is spreading, plowing or both and can even relay the spreader's salt discharge rate.

Smart snowfighting, however, is more than the sum of RWIS and GPS. It depends on the integration and analysis of the information produced by those technologies. And, because of the massive amount of information, their integration also is highly automated.

The next frontier

MDSS integrates information on road weather conditions and forecasts, labor and equipment dispositions, as well as a department's objectives, priorities and plans. Using the agency's profile and winter maintenance plan, the software program integrates information throughout the storm's duration — including forecasts for snow, rain and ice — and recommends optimized pretreatment times, and in-storm application rates and timing. Ultimately, the Internet-based system will be able to deliver route-specific forecasts to drivers.

“MDSS users can select a maintenance route, look at the predicted weather and road conditions, and view a recommended treatment plan,” says William Mahoney, director of the Weather Systems and Assessment Program at the Boulder, Colo.-based National Center for Atmospheric Research, one of the six national laboratories developing MDSS. “They also can pose ‘what if’ scenarios by editing the recommended treatment plan and seeing what would happen if they took no action, used the recommended treatment plan or employed some modification of the recommended treatment.”

With support from the FHWA, the South Dakota and Iowa DOTs have used MDSS for the past three winters. This winter, eight states tested the technology, and another 17 states and the District of Columbia tested the latest version of MDSS.

Maryland DOT has completed an MDSS pilot test, and similar projects are under way in Indianapolis, the New York State Thruway and by a Colorado consortium that includes Colorado DOT and Denver. Eventually, the technology will reach cities and counties because each state agency will customize its system for local conditions and policies.

As the system continues to evolve, users will be able to see maps of their jurisdiction and select roadways to get a closer view of actual road conditions. System users also will be able to select pre-determined routes, which will graphically display road and air temperatures, precipitation, road surface conditions and maintenance actions.

MDSS will be able to generate simulations of proposed interventions to mitigate winter road problems showing their effect on surfaces and recommending further treatment. The tool also will be able to tell users the snow depth, amount of ice and forecast outcomes for various maintenance actions and their effect on highway drivers' mobility.

MDSS will recommend various snowfighting materials, material blends and reapplication times, and will automatically consider the implications for labor and equipment. Probably its biggest cost benefit, though, will be to help the agency determine the appropriate time for its crews to begin treatment. Crews sitting in trucks working overtime waiting for a storm is expensive. Agencies also should expect to recoup some of their investment in MDSS when they optimize the rates and amounts of materials used.

MDSS will capture each agency's unique situations and policies governing response, such as rules on calling out crews. “[That] shouldn't be too complex,” says Bret Hodne, superintendent of public works for West Des Moines, Iowa. “Most agencies have these policies down on paper today. It should almost be ‘plug and play.’” Hodne says that “MDSS should bring a little more formality to our decision process and minimize shooting-from-the-hip.” He also sees the technology being able to capture veteran snowfighters' experiences, which will benefit younger, less-experienced managers, as well as agencies with small staffs.

To most managers, snowfighting still comes down to keeping people safe on the roads. Most agencies still use a low-tech performance measure: the number and intensity of the complaints.

Nevertheless, RWIS, GIS and MDSS are making their mark on snowfighting through faster and more accurate measurement of all conditions that affect the roads. And, what gets better measured, gets better managed.

Richard Hanneman is president of the Alexandria, Va.-based Salt Institute.