Stewardship practice requires the careful review of use of sand in areas with the following issues: [N]

• PM10 (dust) related air quality problems;
• Potential for in spawning streams, shallow lakes or ponds;
• Sensitive, rare plants near the roadside; and,
• Sand is considered to have a negative impact on aesthetics.

The Montana Department of Transportation (MDT) and the Western Transportation Institute have developed “Recommendations for Winter Traction Materials Management on Roadways Adjacent to Bodies of Water.” [N] That study and MDT practice recommended the following:

• Identify areas where road sand may be impacting streams adjacent to highways.[N]
• Wherever possible, a combination of both structural and non-structural BMPs, or best management practices, should be employed to minimize the environmental impacts of winter traction materials. Structural BMPs treat or mitigate highway runoff after it goes off the roadways, and non-structural BMPs reduce the amount of traction materials applied on roadways while maintaining winter mobility and public safety. Strategies can be implemented in the domain of technology, management, or both.
• Strategies may vary, depending on the specific climate, site, and traffic conditions. The crux is selecting an appropriate suite of BMPs that can function most effectively for a given set of conditions.
• Despite the challenges of winter conditions, structural BMPs such as ponds, wetlands, and vegetated swales and filter strips, can still remove high levels of sediment from runoff if designed, sited, installed, and maintained properly.
• The primary non-structural BMPs used to reduce the use and thus minimize the environmental impacts of winter traction materials, include: incorporating environmental staff into construction and maintenance, proper training of maintenance professionals, erosion control, snow fences, snow storage, street sweeping, improved anti-icing and de-icing practices, improved sanding practices, appropriate application rate, and snowplow technologies. Among these, anti-icing strategies, road weather information systems, the Maintenance Decision Support System, and advanced snowplow technologies were highly recommended.

In some areas, MDT is trying to more quickly achieve a bare road, in order to reduce the traction materials needed. [N]

Since 1989 Caltrans has substantially reduced the amount of traction sand applied to the highways in the Lake Tahoe Basin through a combination of deploying state-of-the-art sanding equipment, operator training, and the employment of anti-icing strategies. [N] Caltrans has significantly increased the amount of sand recovery, mainly due to the deployment and use of state-of-the-art vactor and sweeper equipment. [N]

The Iowa Department of Transportation and the Iowa Highway Research Board study on “The Use of Abrasives in Winter Maintenance“ recommends the following stewardship practices for effective and minimal use of abrasives on the following categories of roadways: [N]

• High Speed Urban Roads. For urban streets with posted speed limits above 30 mph, there is no significant value in placing abrasives. Research recommends plowing and applying chemicals to achieve bare pavement.
• Low Speed Urban Roads. For urban streets with posted speed limits less than 30 mph, there is less abrasive dispersion. Abrasives should be limited to parts of the road where motorists must brake, accelerate, or maneuver. Even then, abrasives should be applied only when it will likely take a long time to provide bare pavement.
• Urban Intersections. Urban intersections are relatively low-speed traffic locations. Abrasives could be placed if needed. However, they should be used only when an intersection might be snow or ice-covered beyond a normal period.
• Rural Roads. Both paved and gravel roads can expect to see high-speed traffic. Abrasives will not stay on the road for any reasonable amount of time. Abrasives should be applied on hills and curves only on low-speed low-volume roads. Paved rural roads should be plowed and chemical applied to achieve bare pavement. The recommended gravel rural roads approach should be simply to groom the snow pack.
• Rural Intersections. Again, gravel versus paved roads must be considered. An intersec­tion should be considered “paved” only if all intersecting roads are paved. Road segments where motorists must stop or yield are low-speed traffic locations. Abrasives could be placed if needed. The preferred approach for paved roads is to plow and apply chemicals to achieve bare pavement. On gravel parts of intersections, abrasives may be applied over that part of the road where speeds of less than 30 mph are expected.