As another winter storm barreled down on the Northern Virginia area, homeowners rushed out for bags of rock salt, only to find the store shelves empty.
Home Depot in Springfield tried to make it easy with a sign, "We are all out of rock salt, ice melt and snow shovels," at the door, but people wanted more information.
Rosemary Demanti had stocked up on salt in the fall, but she was almost out.
"Fischer’s on Saturday, they didn't have any," Demanti said. "Giant's out. This was the last choice. We're anticipating more snow."
Hanna Cheves was on a payback mission.
"I borrowed my neighbor’s bag, and I have to pay them back," she said, before entering the store and asking when they'd get more.
Spreading salt on walkways and driveways is an effortless way to combat ice. Although it saves the back pain associated with shoveling, salt can only do so much when it snows several inches. When it comes down to an inch of ice, a shovel won't do much good.
The management at Home Depot didn't have any answers, either. Rumors floated around the store that a shipment of salt was supposed to arrive on Monday, Feb. 2, but it was delayed.
"We don't know. It's supposed to be on its way," one manager said.
The story at Fischer's was the same. Paul Quinter, garden manager, said pallets of salt are only in the store for hours at a time.
"Yesterday, we received four pallets of 50-pound bags, and they were gone in two hours," Quinter said on Tuesday, Feb. 3.
ACCORDING TO the Salt Institute, 15 million tons of de-icing salt are used each year in the United States and four to five millions in Canada. Salt works on sidewalks and streets because it creates a brine that has a lower freezing temperature than the surrounding ice or snow.
Homeowners use a fraction of the salt the Virginia Department of Transportation (VDOT) uses every year. According to VDOT information, 20 strategically-located storage areas are spread throughout Northern Virginia, housing 40,000 tons of sand, 53,000 tons of salt and 121,000 gallons of calcium chloride. Every storm, the supplies are replenished. As of the end of January, VDOT spent about $48 million for snow preparation and removal this winter season. This includes the estimated $20 million cost of the latest statewide snowstorm that occurred during the week of Jan. 25, VDOT information stated.
VDOT has a total snow preparation and removal budget of $80 million for this winter season, according to VDOT information.
David Salisbury, VDOT procurement specialist, keeps tabs on the salt use. It comes in on ships and is stored at the Baltimore harbor, before VDOT purchases it through local distributors. Salt deposits under the Great Lakes are one source VDOT uses, as well as supplies from Louisiana, New York, Chile or the Caribbean.
"Right outside Cleveland there's a big mine," Salisbury said. “They're a 24-7 operation during the winter."
Locally, Quinter has dealers in Norfolk; Baltimore; Martinsburg, W.Va.; and Newington. He orders in homeowner quantities, though.
"We just scramble around wherever we can get it," Quinter said.
MOST OF the 20 dome-shaped storage areas around Northern Virginia can hold 5,000 tons, but a larger dome in Prince William County holds up to 20,000 tons. The dome shaped structure is constructed like that for more capacity.
Salt is most effective after the snow has accumulated about an inch and the temperature is above 20 degrees. Under those conditions, the salt and snow form a slush that can be plowed off the road. Below 20 degrees, the salt will be ineffective melting the snow and ice.
In addition to salt as an anti-icing agent, magnesium chloride is being used. It works like anti-freeze and is less toxic than salt. It is more expensive than salt but less corrosive, so costly rust repair is not needed, according to the Idaho Transportation Department's information. Morteza Salehi, VDOT assistant district engineer for maintenance, is familiar with the magnesium chloride mixture. Although it sounds more high-tech than salt, it's nothing new.
"It's mixed with salt and wets the salt, so it sticks better," Salehi said. "It raises the melting point and lowers the freezing point, and makes the anti-icing a more effective process."
Salt takes its toll on cars as well as other steel surfaces it comes in contact with. The Salt Institute does not deny that salt is harsh on cars but claims that "cars will rust even where de-icing salt is not used, particularly in warm coastal areas and in wet climates."
The salt does take a toll on bridges and road construction materials that include steel supports. Efforts are made to combat this, though, according to Steve Titunik at VDOT.
"That's why we coat steel rebar," he said. Rebar is the steel support rods used in concrete.
Fischer's hardware carries rock salt, potassium chloride, calcium chloride and urea. Arlington resident Norman Zalfa uses urea because it's easy on his bricks.
"Urea is safe for stone and brick," Quinter said.
The history of salt as an anti-icing device on roads dates back to 1938, when the New Hampshire State Highway Department used it on an experimental basis, according to a government publication "Better Roads."
As far as Rosemary Demanti's walkway in Springfield is concerned, the "No Salt" sign left her with few choices.
"I'm going to be using table salt," she joked.