The world of winter maintenance is changing. Forward-thinking contractors are dialing in their use of salt to cut material costs and reduce damages to landscaping and hardscaping from the overuse of chlorides. Precision applications of salt based on pavement temperature and the incorporation of liquid deicers are delivering faster results and higher levels of service than non-scientific salting practices. The following case studies from Wisconsin municipalities exemplify key smart salting practices that readily translate to the work of private contractors.

Lesson #1 - Calibration insights

The City of Cudahy, WI, just south of Milwaukee, first calibrated its salt trucks in 2013. During that initial calibration, they learned that one of their vehicles was putting down almost three times more salt per lane mile than they thought – that’s hundreds more pounds of salt per lane mile than was needed. Proper calibration of the entire fleet dropped its overall salt use by 40% that first winter.

Cudahy’s story is not unique. Identical pieces of equipment often apply salt at wildly different rates, but it’s nearly impossible to know what you’re putting down until you measure it. Calibrating salt application equipment is a crucial step that enables applicators to adjust rates based on pavement temperatures and weather trends.

Lesson #2 - Application rate adjustments

While a given amount of salt will always melt a given amount of snow, the rate of melting speeds up as temperatures climb. That means that less salt is needed at warmer temperatures.


The City of Stevens Point places application rate charts in the cabs of its vehicles to remind drivers how much salt is recommended at various pavement temperatures.

Drivers have pavement temperature readings available on the dash, which provide guidance for the right amount of salt to apply. This pavement temperature reading is more important for salt application than air temperature, which can be different. The amount of salt that they’re applying per lane mile almost triples at the coldest temperatures.

Below 15°F, they adjust not only their rates, but also the material that they’re applying. Rock salt is effective down to 15° to 20°F. When temperatures plummet into the teens and below, deicing will require the use of alternatives like magnesium chloride or calcium chloride.

View the Winter Maintenance Salt Application Guidelines and Calculator for general recommendations for various deicers and temperatures here.

Lesson #3 - Embracing liquids

The City of Appleton, WI, began utilizing salt brine for pre-wetting salt in 2007. The benefits were immediately evident with a faster improvement in pavement conditions. Why are liquid deicers so speedy? Rock salt needs moisture to begin the melting process. Liquid deicers, where salt is already in solution, are activated so melting begins immediately. Adding salt brine to rock salt is comparable to adding a little lighter fluid to charcoal briquettes; you speed up melting and the achievement of your desired result.

After experiencing the power of liquids in pre-wetting salt, municipalities often begin utilizing brine in anti-icing treatments before appropriate storm events. Anti-icing can be extremely effective in preventing snow from bonding to pavement and facilitates removal with plows. They may begin experimenting with creating slurries with much higher ratios of liquid to solid (60-80 gallons/ton), implementing "shake and bake" techniques in which high rates of liquid are applied over rock salt, or transitioning to liquid-only routes.

In 2021, the City of Appleton bumped up the amount of salt brine it used for pre-wet to the maximum amount possible with their current equipment. As they update their fleet, they plan to purchase trucks with even greater liquid capacity.

Take a page from municipalities

With the cost of salt almost tripling in the last 20 years, municipalities realize huge savings when they move to precision salt applications. Additionally, as property owners, they benefit greatly from the reduction in damage to infrastructure and vegetation. It’s estimated that a ton of rock salt does between $800 and $3,000 of damage in the premature aging of roads, bridges, etc. Finally, many municipalities are measuring marked increases of sodium in drinking water wells due to salt. Right-sizing salt use is their best bet for ensuring the health and safety of drinking water long-term.

The priorities of municipalities and contractors may vary. At the end of the day a contractor needs to keep the customer happy and protect the bottom line. Because the norms of salt use have shifted to "the more, the better," municipal priorities of using less salt may clash with contractor priorities of ensuring customer satisfaction. These priorities can be reconciled through ongoing education of property owners and property managers about salt application best practices. When customers understand that more salt does not necessarily mean a safer surface, and that winter maintenance can be successfully carried out with precision salt application, that understanding can help contractors align with municipal salt reduction priorities.

Allison Madison is Program Manager for Wisconsin Salt Wise, a coalition of organizations working together to reduce salt pollution in lakes, streams and drinking water. Email her at wisaltwise@gmail.com. Learn more about WI Salt Wise, including its webinar series on smart salting, at www.wisaltwise.com.