Price of rock salt diverges greatly from city to city

CEDAR RAPIDS - Once you get the gold market figured out, try to figure out the price of rock salt.

Many Iowa cities and counties buy their annual wintertime supply of rock salt through the bidding process of the Iowa Department of Transportation with the thought that strength in numbers will secure better prices than the price an individual jurisdiction might secure on its own.

The DOT bid process, though, results in a wide range of different prices for different cities and counties and for different DOT garages based on, among other variables, location, distance from a salt mine or salt stockpile and proximity to a river terminal or rail stop, reports Dena Gray-Fisher, spokeswoman for the DOT in Ames.

The city of Cedar Rapids is purchasing 8,000 tons of rock salt for the winter at $69.38 per ton, while the city of Iowa City is purchasing 3,000 tons at $62.68 a ton.

Cedar Rapids could save $53,600 on its purchase if it enjoyed the price that Iowa City got in the DOT bid, but, by comparison in Linn County, the city of Marion is paying $70.12 a ton, the city of Robins, $72.12 a ton and the city of Mount Vernon, $73.07 a ton. And in Johnson County, the city of North Liberty's price is $72.93 a ton and Coralville's price is $67.24 a ton, according to information provided by the DOT's bid documents.

At the high end, the DOT documents note that the price for Sac City in western Iowa is $95.88 a ton and Cherokee and Storm Lake is $94.94 a ton.

The price of rock salt arriving at a DOT garage at Sioux City costs $58.60 a ton, at a DOT garage at Iowa City, $59.02 a ton, and a DOT garage in Storm Lake, $83.12 a ton, according to state figures.

Craig Hanson, Cedar Rapids' public works maintenance manager, reports that the city of Cedar Rapids sought its own price for rock salt a year ago, only to discover that the go-it-alone approach couldn't compete with the in-it-together prices secured by the Iowa Department of Transportation.

A year ago, the DOT bid price for Cedar Rapids was $68.02 a ton, compared to prices ranging from $68.67 to $74.49 a ton from three bidders for a Cedar Rapids-only contract, according to city figures.

Cedar Rapids has 5,300 tons of rock salt on hand as the new delivery arrives at the rate of 25 tons of salt per semi-truck load, Hanson says.

He reports the city needed 8,500 tons of rock salt last winter when the official snowfall total at the airport was 32.5 inches, though he says the snow total was measured at 39.3 inches at a site in northern Cedar Rapids.

Hanson says several smaller snows can drive up the city's use of salt and sand, compared to a winter when much of the snow comes in a few large snows, as it did last winter.

The city used more than 11,000 tons of rock salt in the rough winter of 2007-2008, in which the city saw 59.9 inches of snow, he reports.

The average snowfall from 1981 through 2010 in Cedar Rapids was 25.5 inches as measured at the airport and 31.5 inches in northern Cedar Rapids, Hanson adds.

The city puts salt directly on streets, but it also makes a brine using the salt to pre-treat streets before they ice up. The city needs to use less salt after storms because it now uses more of the salt-brine mix before storms, Hanson says.

In the winter of 2007-2008, the city purchased 25,000 gallons of salt brine from the Iowa Department of Transportation. The city bought its own brine-making equipment in 2008, and last winter, the city put down 190,000 gallons of brine on the city's streets, Hanson reports.