Leaders use best practices, training, outreach to reduce salt use
The Freshwater Society announced its Environmental Leadership Awards at the 16th Annual Road Salt Symposium in February. The awards recognize those who champion efforts to reduce chloride pollution. Below, this year’s champions share how they reduced their road salt while maintaining safety.
To nominate candidates or suggest topics for the 2018 symposium, please contact Connie Fortin, 763-478-3606, firstname.lastname@example.org.
City of Woodbury
The city has worked to get out the message that salt use causes irreversible damage to its lakes, ponds, and groundwater. It has shared the need for change with the city council, staff, and residents. The November city newsletter featured "Smart Salting" to start preparing residents for changes in practice.
Other changes include improved equipment:
- Plow trucks are now equipped with road temperature and ambient air sensors that help crews determine what material to use and the application rate.
- Crews started using and converting truck plows with a rubber blade that conforms to the road, giving a cleaner surface, using less material, and reducing noise levels.
- Trucks have computerized salters that are ground-speed-orientated and calibrated every year to make sure the application rate is correct and at a minimum.
In addition, the city uses best practices to reduce material use and protect the environment:
- Salt is stored in an enclosed facility.
- Salt is supplemented with calcium chloride for colder temperatures to jumpstart the melting process. It also helps lower salt’s effective working temperature and reduces rock salt bounce.
- Streets are swept every spring and fall, and testing is performed to look for contamination.
- Spinner settings were reduced to get the greatest results for a safe roadway.
- A 90% salt–10% sand mixture is used when temperatures are below 15 degrees so there is some type of abrasive left on the road to act like sandpaper to the surface.
- Materials are tracked and application rates observed for melting, and observations are shared to improve operations and learn from each other.
- Pre- and post-event meetings are held to evaluate results and make adjustments.
City of Jordan
Jordan’s public works department saved the city $18,500 in upfront equipment costs for a pre-wetting system. The department bought an old farm sprayer and four 20-gallon plastic tanks, and used a tank it already had to make brine. A local metal fabrication company made brackets to hang the system on the trucks. This equipment cost the city only $1,500.
In the first year of use, the city used gravity to get the brine into the salt system. In the second year, the crew added small pumps on the trucks to pressurize the system and get more of the liquid out onto the salt. This past winter, the city upgraded the pre-wet system by adding a second spray tip to add more brine to the salt.
With the improved pre-wet system, the city also changed how it plowed streets. It salts only the hills and intersections until the snow has stopped, and adds Road Guard™ Plus 8 to the salt brine when temperatures get below 10 degrees.
These changes in practice have not only cut the salt use in half but also reduced equipment wear and tear and saved thousands of dollars in fuel.
St. Cloud VA Facilities Management
Since 2011, all Garage Operations employees have attended Winter Parking Lot and Sidewalk Maintenance Training and have become certified in snow and ice control best management practices. Employees have agreed to apply best management practices to reduce chloride impacts.
Facilities Management purchased a new salt spreader after the initial training class in 2011. The new spreader has allowed operators to use brine to pretreat paved surfaces before storms and allows for pre-wetting rock salt before it hits paved surfaces. The first year the new spreader was put into use, the St. Cloud VA achieved a 50% reduction in rock salt use.
Park Nicollet Health Services
Over the past few snow seasons, Park Nicollet increased its commitment to help the environment. As a result, it greatly reduced the amount of salt used and reduced costs. Process improvements included increased use of liquids, pretreatment, and pre-wetting. Use of liquid brine began in the winter of 2013–14 to reduce the volume of granular salt. This showed a 45% salt reduction in 2014–15 and an additional 28% reduction in 2015–16. Landscape damage caused by salt has been reduced by more than 75%.
Curt Pape – Minnesota Department of Transportation, Individual Award
Curt Pape was instrumental in bringing the Maintenance Decision Support System (MDSS), Mobile Data Computer, and automated vehicle location to MnDOT. This system provides real-time route-specific information to the driver about weather and pavement condition and recommendations about how much salt to use to restore the bare driving-lane condition in the time allowed by performance target. The system records the pavement and weather conditions, the recommendations, and the amount of salt actually applied to the road by the driver. The use of MDSS has shown promising results, with a range of up to 50% salt savings.