Snow and ice control

This catalog of spreader types was created as part of Clear Roads project CR12-05, "Comparison of Material Distribution Systems for Winter Maintenance - Phase I," published December 2014.

In the winter season, Departments of Transportation (DOTs) need to maintain a certain level of service to keep the roadways safe for the motoring public. This coupled with budgetary and environmental constraints makes decisions challenging for snow fighters when it comes to purchasing, scheduling and managing their resources. Very important tools for keeping the roadways clear and safe are salt spreading systems. This study gathered and compared information about salt spreaders from state and local DOTs. The references, examples, comparisons, photographs and test proposals contained in this report seek to make the current practices of DOTs available to as wide an audience as possible.

This research brief was created as part of Clear Roads project CR11-04, "Snow Removal at Extreme Temperatures," published March 2013.

Extremely cold winter storms (below about 10°F) bring about different considerations for taking care of roads than warmer winter storms, where granular salt and salt brine are cost-effective measures of melting snow and ice when used in combination with other operations (e.g., plowing). At temperatures lower than about 10°F, either extremely large quantities of salt are needed or no amount of salt can melt snow or ice pack. Best practices for using chemicals during extremely cold winter storms include: waiting until the end of the storm, using deicers in daylight hours only, mixing salt with MgCl2, CaCl2, and/or agriculture by-products, and using high application rates. Despite their environmental and hidden costs (air pollution, sedimentation, spring cleanup & disposal), abrasives are frequently used during extreme temperatures to provide temporary traction. Best practices for using abrasives during severe cold includes prewetting with liquid deicers (although not plain salt brine-it may freeze) or hot water. Innovative strategies continue to be tested at severe temperatures, including conductive pavements and geothermal systems, which have demonstrated to be potentially effective tools.

This research brief was created as part of Clear Roads project CR16-05, "Weather Event Reconstruction and Analysis Tool," published January 2020.

The Clear Roads research consortium requested a tool to help transportation agencies more quickly and easily reconstruct winter weather events by drawing from data sources that cover the entire United States. The goals were to help agencies better understand the development and outcomes of hazardous weather events, react appropriately to them in the short and long term, and refine future maintenance decision-making. The tool would assist with after-action reviews and inform changes to practices at state, county and municipal levels of government. During Clear Roads Project 16-05, the research team designed and built a web-based tool that accesses multiple types of weather data in order for a user to reconstruct what happened during a weather event. This final report describes the steps taken to accomplish this objective. They include: identifying appropriate weather data and locating the best online sources, sketching a mock version of the web-based tool, and, upon Clear Roads approval of the design, building and testing the tool. A guidance document was produced and technical support was provided to the Clear Roads users for one year.

Winter storms have increased in frequency and intensity since the 1950s, and average annual precipitation is projected to continue to increase across the northern United States. In response to these trends, many states have developed, or are interested in developing, emergency-response plans for extreme winter storm events. This report provides a series of six emergency-response plan case studies as well as a synthesis of best practices related to emergency-response planning for extreme winter weather. It is intended to provide a blueprint for transportation agencies seeking to develop or improve their own extreme winter weather emergency-response plans, including how to coordinate an effective response across multiple agencies and jurisdictions.

This project was conducted by the Midwestern Regional Climate Center (MRCC) at the University of Illinois and jointly funded by the Clear Roads and Aurora pooled fund studies. The project’s goal was to enhance the MRCC’s Accumulated Winter Season Severity Index (AWSSI) tool with data from additional locations and added functionality. The project had four tasks: Task 1: Add at least one additional AWSSI location to each Clear Roads state. Task 2: Add the ability to overlay past years on the current-year AWSSI time-series plot. Task 3: Display projected information for the remainder of the winter season. Task 4: Determine the feasibility of an augmented “Road AWSSI” tool. In lieu of a final report, this Project Summary briefly describes the MRCC investigators’ process in completing these tasks, including methodology, research, results and recommendations.

This research brief was created as part of Clear Roads project CR16-01, "Utilization of AVL/GPS Technology: Case Studies," published June 2018.

Winter road maintenance accounts for roughly 20 percent of state DOT maintenance budgets. State and local agencies spend over $2.3 billion on winter operations annually. As such, effective winter maintenance operations incorporating smart uses of methods, techniques, technologies, equipment and materials becomes essential. Among various winter maintenance technologies, automated vehicle location (AVL) and global positioning systems (GPS) have been widely used by transportation agencies to monitor vehicle locations and equipment operational status for winter road maintenance operations. This report summarizes the information gathered during the study conducted for the Clear Roads project entitled Utilization of AVL/GPS Technology: Case Studies. The research team surveyed multiple state DOTs on the current state of AVL/GPS system usage for the purpose of gathering information on the planning, processes, steps, and results observed by agencies with their respective systems. Six state DOTs (Utah, Washington State, Michigan, Wisconsin, Nebraska, and Colorado) were selected to conduct detailed case studies. The case studies were performed through in-person interviews with multiple levels of DOT staff involved in AVL/GPS system planning, procurement, implementation, management and operations. This final report summarizes the key results, findings and lessons learned from the case studies. It also identifies best practices and provides a series of recommendations for winter maintenance agencies to consider in the procurement, deployment and integration of an AVL/GPS system for winter maintenance operations.