The cost of using deicing salts are enormous. These cost include:
On average, over 10 million tons of salt is used each year. The price of salt is about $30 per ton delivered. This amounts to an annual expense of over $300 million. An additional $250 million is spent on equipment and labor for spreading, handling, and storage. Nearly $500 million more is spent annually by highway agencies to purchase, maintain, and operate snow and ice control equipment.
In 1989 approximately 15.4 million new passenger vehicles were sold nationwide, including 9.9 million cars, 4.6 million vans and light trucks (mostly pickups), and 900,000 large trucks, trailers, and recreational vehicles. The average cost to protect these vehicles from corrosion is $500 per vehicle. Thus, about $7.7 billion is spent on corrosion protection per year. (Note: corrosion protection dose not exclusively mean corrosion due to salt.) If calcium chloride and salt were not used, the total savings from the salt-related corrosion protection would range from $1.9 to $3.9 billion per year.
To estimate the average annual cost of repairing damaged decks due to deicing salt, assume that 1 in 10 decks will need to be rehabilitated each year. The typical surface area of a deck is 7,000 ft2. The average cost of fixing a concrete deck, whereby the concrete is replaced and rebars are cleaned, is about $20 to $40/ft2. This comes to about $50 million to $200 million a year. These values will decrease as more of the older roads and decks are fixed. In order to protect these newer decks against further corrosion through the use of improved drainage and special overlays that impede migration of chloride into the concrete, the average cost is about $75 to $125 million per year.
Compared to deck damage, deterioration of other bridge components can be more expensive and difficult to repair. The cost of maintenance for bridge components can range between $125 million to $325 million per year.
In repairing a parking garage, the cost is about
$7.50/ft2. The average surface area of a parking
garage is 150,000 ft2. This comes to $50 to $150
million per year to repair 50 to 150 garages. Protection costs
are an additional $25 million a year for 200 parking garages.
There is not enough conclusive data to estimate the cost of damages to underground structures, but it is probably at least $150 million or more a year.
Deicing is a very expensive proposition. The cost of producing, buying, storing, distributing, and damages done be these deicing salts is in the tens of billions of dollars a year. So, why do it? We do it because society is unwilling to accept the extremely high economic and health cost of not deicing. However, by continuing to find better deicing agents, we can expect to cut down on the cost of deicing our highways and byways in the winter.
