How to Use Less Salt on Roads and Parking Lots

Why roads and lots need chemicals at all

Chemicals do three jobs in winter. They keep ice from forming, they keep snow and ice from bonding to the pavement, and they help melt ice that has already bonded.

The reason is safety. Ice cuts surface friction, so stopping distances grow and crashes, slips and falls go up. Each year, 24% of weather-related vehicle crashes happen on snowy, slushy or icy pavement, according to the Federal Highway Administration. Agencies such as state DOTs have a legal duty to keep roads clear, and falling short can lead to liability lawsuits. Contractors carry the same kind of risk on every lot and walkway they service.

U.S. road agencies have used salt since the 1940s. Annual use has grown from about 0.15 metric tons per year then to roughly 21 million metric tons now. Highway deicing accounted for about 41% of all the salt used in the U.S. in 2024, according to the U.S. Geological Survey.

What salt costs beyond the purchase price

The purchase price is only the start, and it isn’t small. In the 2014–15 season, the average price of salt rose from $38.30 to $46.80 a ton. Some buyers had to prepay 80% of their stocking order in early fall. In 2014, salt production was worth $2.2 billion, and 43% of sales went to deicing. Winter road maintenance takes roughly 20% of state DOT maintenance budgets, according to the Federal Highway Administration.

The bigger costs come after the salt is down.

Your pavement

Salt lowers the temperature at which water freezes. That keeps pavement clear, but it also creates an artificial freeze-thaw cycle on highways and parking lots alike. Meltwater seeps into cracks, refreezes when the temperature drops, expands and breaks the pavement apart. The more often that cycle repeats, the more potholes and spring repairs you face. See What Does Ice Do To Your Roads? and 3 Avoidable Things That Cause Low-Bid Blades to Severely Damage Roads.

Bridges, structures and equipment

All chlorides cause rust and decay. Sodium, calcium and magnesium chloride eat away at bridge decks and the steel inside concrete. They also attack the trucks and spreaders that put them down.

Water, plants and wildlife

Salt doesn’t stay where you spread it. A U.S. Geological Survey study found road-salt chloride rising substantially in 84% of the urban streams it tracked. At 29% of sites, chloride stayed above the EPA’s chronic level for aquatic life for more than 100 days a year.

• 84%of urban streams tracked showed rising road-salt chloride
• 29%of sites stayed above the EPA’s chronic level for aquatic life 100+ days a year

• Groundwater. Salt lingers in groundwater for a long time, and wells that take on too much salt may have to be shut down.
• Lakes and streams. Salty water sinks and forms a dense layer at the bottom of ponds and lakes that traps nutrients. Saltier water harms invertebrates, fish and amphibians.
• Plants. Roadside trees and plants show leaf damage and dieback, sometimes well back from the road.
• Wildlife. Animals that drink salty water can get salt poisoning. Small birds mistake salt crystals for grit, and even a small amount can kill them.

Choosing a deicer

Salt doesn’t lower water’s freezing point to one fixed temperature. How well it works depends on how cold the pavement is. Rock salt can melt ice down to −6°F, but its lowest practical melting temperature is a 15°F pavement temperature. Below that it works too slowly to count on, according to the Minnesota Pollution Control Agency.

Rock salt is the most common deicer because it’s cheap. Other chlorides and acetates work on colder pavement or corrode less, but they cost more.

• Rock salt (sodium chloride)

  Lowest practical pavement temperature

  15°F

• Calcium chloride

  Lowest practical pavement temperature

  −20°F

• Magnesium chloride

  Lowest practical pavement temperature

  −10°F

• Potassium acetate

  Lowest practical pavement temperature

  −15°F

• Calcium magnesium acetate (CMA)

  Lowest practical pavement temperature

  20°F

Source: Minnesota Pollution Control Agency

Non-chloride deicers are rare on public roads because of their cost and the scale involved. Airports use them, but they pay far more, and few road agencies or contractors have that kind of budget.

Additives mixed with salt can improve how it performs and cut the total you need, but they don’t replace it. Researchers are also testing farm byproducts such as beet juice and cheese brine.

Short-term: apply the right amount

Over-application is one of the most common problems in winter maintenance. Salt beyond what the conditions call for costs money and adds no safety.

For DOT and municipal fleets

Set your rates by pavement temperature and the type of storm, not by habit. Check your spreaders so the rate you set is the rate you get. Then track what each route actually uses. Anti-icing before a storm keeps snow from bonding to the pavement, so plows clear more and you spread less afterward.

For commercial contractors

Liability pushes contractors to salt heavily. But once the surface is covered, extra salt doesn’t make a lot or walkway any safer. Plow or shovel first, so the salt works on the ice that’s left instead of on loose snow. Match your rate to the pavement temperature, check your spreaders, and sweep up leftover salt after the storm. Using less also cuts your material costs on every visit.

Long-term: plow more, salt less

The less snow and ice your plows leave behind, the less chemical you need to finish the job. Blades that scrape cleaner remove more on the first pass, and chemicals work better on a clean surface. Low-bid blades wear down fast and leave more behind, so it’s time to ditch them for good.

For DOT and municipal fleets

The Winter Carbide™ cutting edge systems are built to last. Each is rated against a standard tungsten carbide insert cutting edge:

• Razor® with Winter Carbide™A 2x WearFactor, or twice the wear life.View the system ›
• Razor® XL with Winter Carbide™A 3x WearFactor.View the system ›
• BlockBuster® with Winter Carbide™A 4x WearFactor, built for heavy-duty routes.View the system ›

For commercial contractors

Winter Carbide™ is built into contractor systems too. Both of these are rated to last 10 times longer than the OEM’s hardened steel:

• Pegasus® Expandable Plow Cutting Edge SystemFor Western WIDE-OUT expandable plows.View the system ›
• Razor® Arrow Straight Blade SystemFor Western PRO PLUS straight blades.View the system ›

Choose a blade company that acts as a partner, not just a vendor. A free consultation matches the blade to how you plow.

Frequently asked questions