A salty tale

Jan. 28, 2009

Salt saves lives. That said, it’s easy to understand the anxiety in 2008 that gripped public works officials throughout those portions of the American snowbelt that customarily obtain their salt from mines in the Great Lakes, Kansas, Texas and Louisiana. Questions of “Will we be able to get enough salt?” and “What can we do to stretch our valuable salt supplies?” have received wide publicity.

Salt saves lives. That said, it’s easy to understand the anxiety in 2008 that gripped public works officials throughout those portions of the American snowbelt that customarily obtain their salt from mines in the Great Lakes, Kansas, Texas and Louisiana. Questions of “Will we be able to get enough salt?” and “What can we do to stretch our valuable salt supplies?” have received wide publicity.

Sorting out fact from fantasy may yield some lessons for future winters. For this year, the die has been cast, and nature will determine whether our preparations have been sufficient. Despite our faith in the technology of road weather information systems, when it comes to predicting winter weather, we have not improved on the wisdom of the Romans. Eminent Roman scholar and scientist Pliny the Elder observed: “The only certainty is than nothing is certain.” Meteorologists tell us about El Niños and La Niñas. These weather phenomena may affect probabilities, but the only certainty is that winter will come. Snow “emergencies” are totally predictable—by season if not by their exact timing. Equally predictable is the customer demand by motorists and shippers that snow and ice be removed and safe driving conditions restored.

Last winter, record snowfall in much of the upper Mississippi River basin found many state and local agencies scrambling to find enough salt to keep their roads safe. When early snows signaled a severe winter, salt mines kicked up production rates to full capacity (24/7 except for necessary downtime for equipment maintenance). Road salt production surged 12.4%. Mayors and governors felt they had dodged a bullet when their public works departments and state transportation agencies were able to find enough salt to maintain service levels. In scouring news reports, we found only one city was reduced to closing thoroughfares for lack of salt. None of us wants to resort to the extremity of closing a road except in severe blizzard conditions.

Last year’s heroic snowfighting efforts, however, left both customers and salt miners tapped out at the end of the winter. At winter’s height, salt mines were loading trucks right from the mine skip. That frenetic production pace has continued all year.

It may not be enough, depending on what nature has in mind for the winter . . . and early and significant snow and ice events in both the Midwest and East suggest the need for concern.

In any case, mayors, councils and county boards began to fret as soon as last winter’s snow melted. Some state DOTs, notably Minnesota and Wisconsin, moved quickly to secure supplies for the 2008-09 winter. Mn/DOT’s bid increased 45,000 tons, while Wisconsin’s jumped 351,000 tons.

And the bid amount is not the key determinant; it’s the cap. Some agencies have contracts that commit them to purchase only a portion of the bid amount while requiring the successful bidder to have a reserve stockpile available ranging in size from half the guaranteed minimum to an amount double the supplier is certain to sell. These reserve requirements set the cap, which determines how much salt is committed to each customer—that is the amount that disappears from the marketplace when a procurement is finalized, even if the agency does not take delivery.

Worry early and often

As summer approached, DOTs in Iowa and Illinois entered their procurement phase. Iowa jumped its bid amounts by 52%, 100,000 tons, while Illinois increased its bid requests by 421,000 tons, 34%. Despite having the available salt mines working around the clock, salt companies faced the unhappy prospect of having insufficient supplies to bid on contracts they might like to secure.

Agencies found “no-bid” responses disquieting. Anxieties grew. While there had been anxious moments in Januaries and Februaries past, the prospect of a salt shortage had never been heard before in July and August.

Deepening the gloom, the market of the upper Mississippi is served largely by barges carrying salt from Louisiana’s three large salt mines. Until this year, the record tonnage was 9.7 million tons in 2004 and the average season’s shipments have been 8.5 million tons since 1996. In 2008, however, spring flooding caused by the melting of the previous winter’s record snowfall denied use of the river’s locks and dams for more than a month. The river opened to shipping later than any year on record and was further interrupted by flooding and high water in May and June.

The supply of salt is virtually endless, but the logistics of extracting it and getting it delivered to customers’ storage sheds is no simple task. Virtually all the tonnage used in the U.S. snowbelt comes from just a dozen mines: three each in Louisiana and Kansas, two each in Ohio, New York and Ontario and one each in Texas and Michigan. There is copious salt underground, but mines are engineered with production limited to available design or equipment; usually, the constraining variable is the hoisting capacity of the production skip. New mines or additional shafts could be created, but a new mine could cost $100 million, and the environmental approvals could take years. Expansions require heavy capital costs difficult in the current financial environment, yet Compass Minerals has made that multimillion-dollar commitment and is midway through a 2 million-ton capacity expansion at its Goderich, Ontario, mine on the Great Lakes, already the largest in the world. That expansion adds 10% to North American rock salt production.

Expanded North American production could be a long-term solution to an expanded market, but it offered little hope for relief in 2008 because the mines were already operating at peak capacity. Fortunately, boundless supplies are available from salt producers in Mexico, Chile, Brazil and Europe.

As a heavy bulk commodity, salt moves most economically by water—by barge on the Mississippi system, by Great Lakes freighters or, for coastal cities, by larger ocean-going cargo ships. When the inland water system is closed by ice each year, salt can be shipped by rail, but at significantly higher cost, or by truck, which is an even costlier alternative. Since ocean ports are open to receive shipments year-round, they can readily access offshore salt. Not so for the upper Mississippi states.

While East Coast ports receive regular shipments of imported salt, the sighting of a 40,000-ton salt freighter in New Orleans is a novelty. The last time there was any significant salt import activity in the Big Easy was 2001. Early reports suggest that record will fall this year . . . along with the record for barge-shipped salt north on the Mississippi.

Whether enough imports can get through before ice closes the river is as unclear as the unknown quantity dictated by winter’s severity. But help in the form of imports into New Orleans began to arrive in September.

They say every cloud has a silver lining, and there are some lessons to treasure that are already apparent. Lesson No. 1 is that agencies need a lot more onsite salt storage facilities . . . and need to get them filled before winter’s snow flies. The state of Wisconsin has committed to a goal of storing 100% of its annual requirement, much as Chicago and Denver do today. The Salt Institute has been recommending this goal for 30 years, but the salt shortage has made these kinds of investments a front-of-mind issue. And the Ohio Department of Transportation (ODOT) has discovered that its procurement method that loads most of the supply risks on salt suppliers is a flawed model.

ODOT also has, like most agencies, rediscovered the virtues of the Salt Institute’s Sensible Salting program as a means of stretching scarce salt supplies. For 40 years, the Salt Institute has been preaching application rates to deliver the minimum amount of salt necessary to meet the required level of service.

And that’s what it’s all about: delivering the level of service required. Plowing and applying salt reduces traffic crashes by 85%, according to a study by Marquette University. And performing winter maintenance prevents 88.3% of the injury crashes that would otherwise occur. Ford Motor Co. may say “Quality is Job 1,” but for public works snowfighters, “Safety is Job 1.”

If public safety is Job 1, then the ability of snowfighters to deliver personal and commercial mobility in winter weather is Job 2. Studies conducted by Global Insight Inc. have found that using the very conservative calculation of only the lost wages, retail sales and tax revenues that occur when storms impair reliable roadway service damages the economy more severely than the cost of an entire winter’s worth of snowfighting expense. Snowfighting may be the best bang for the buck of any government program.

Sand blasted

It remains unclear if public works officials are relearning another important lesson that seemed well established until this winter: Salt and sand mixtures are not the solution to maintain service on paved roads in most winter-storm conditions. The media was filled last fall with interviews by local agency officials explaining that in order to stretch limited salt supplies they intended to either sacrifice service levels or resort to salt-sand mixtures. They claimed reverting to sand would be fiscally prudent in time of constrained budgets. This totally ignores a half-century of experience. While sand itself may be cheap, a sand-based strategy is more expensive than straight salt.

Moreover, a second study by Marquette University examining the cost effectiveness of straight salt compared with using salt-sand mixtures discovered that in terms of reducing traffic crashes, salt paid for itself in a half hour whereas use of salt-sand mixtures never delivered safety benefits to recover its costs.

Alarmed at the retreat from modern snowfighting, Ben Jordan of the Wisconsin Transportation Information Center (TIC) lectured his fellow Badger State snowfighting colleagues, answering the question, Why not sand-salt mix?

“In fact, the assumption that sand-to-salt ratios of 50:50, 60:40, 70:30 or 75:25 are effective treatments is misguided. TIC agrees instead with research that shows mixing salt and sand (beyond the 2-5% salt needed to freeze-proof sand stockpiles) does not improve the effectiveness of either material.

Sand and salt work at cross-purposes. Sand improves traction when it is on top of ice or snow pack. In a salt-sand mix, as the salt begins to melt the snow pack, the sand sinks and mixes with the snow pack. Once the sand is gone from the surface, it does nothing to improve traction. Sand mixed with salt also reduces the melting effectiveness of the salt.

There are other costs of using a salt-sand mix to consider. It usually increases the overall application rate, so actual reduction in salt use and cost savings may be less than expected.

For example, in a change from applying salt at an application rate of 300 lb per lane-mile to a 75:25 sand-salt mix applied at 800 lb per lane-mile, the salt component of the mixture is 200 lb per lane-mile for a 33% reduction. Assuming a salt price of $60 per ton and a sand price of $4 per ton in this scenario, material costs go down only $1.80 per lane-mile. Adjust the equation to a sand-salt ratio of 70:30 and the savings are $0.68 per lane-mile. And mixing two-thirds sand with one-third salt saves nothing in material costs over straight salt.

If the route is 10 centerline miles (20 lane-miles) or more, it may take an additional trip to the yard to refill the sand-salt mix. The labor and equipment costs for this trip wipe out the nominal savings on materials. Add to that the resource outlay for sand cleanup in the spring, and the cost of the mixture is higher.”

The lifesaving, jobs-preserving mission of snowfighters cannot be sacrificed at the altar of professed fiscal concerns. If next summer’s roadway rights-of-way grow a bit shaggier through less frequent mowing, that price is far more acceptable than one school bus skidding into a ditch this winter. Better bet: Use straight salt, but get the equipment and train operators to implement sensible salting.

Winter snow and ice emergency response is inherently risky. Storms may not hit, or they may be overwhelming. We all face these risks together. Working together, salt companies and public works snowfighters can avoid adding to the pressure on hospital emergency rooms and maintain the economic vitality of our communities in severe winter weather. Agencies need a full year’s salt supply under roof before winter and win-win contracts to share risks equitably. There’s plenty of salt. Salt companies need to work with their customers to get it delivered to the right place at the right time. It gives new meaning to the term “Sensible Salting.”

About The Author: Hanneman is the president of the Salt Institute.

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