AGENDA# 5h
TO: Mayor and Town Council
FROM: W. Calvin Horton, Town Manager
SUBJECT: Use of Salt Substitute on Icy Roads
DATE: August 28, 2000
Following snow and ice storms this past winter, a Council member referred the attached article related to a substitute for salt on icy roads and requested information regarding its potential use by the Town.
Staff reviewed the article in the February 2000 edition of “BioCycle World” on a limestone/whey substitute for salt for use on icy roads. We discovered that this material is calcium magnesium acetate (referred to as “CMA” in the literature). Very little data are available as to its cost effectiveness as a substitute for salt as a de-icing agent. The product seems to be in the early stages of testing and only a few states have started using it on a small scale basis.
We did obtain an article dated March 21, 2000, by a member of Ohio State University’s Department of Chemical Engineering which summarized preliminary information related to “CMA”. This study found that “CMA” has a de-icing capability comparable to salt, along with unquantified cost avoidance advantages related to damaging side effects to vehicles, highway concrete, bridges, vegetation or related environmental problems. The study also concluded, however, that the present cost of “CMA” is high relative to salt. That study found that the comparison of cost per ton between “CMA" and salt was $650 to $40 respectively. We will continue to monitor the progress of use of this material once more data are available.
We contacted the Institute for Transportation, Research and Education (ITRE) to obtain information related to salt substitutes, including “CMA”. They reviewed recent studies and reports and did not find conclusive information related to the effectiveness of “CMA”. Generally speaking, however, their information confirms our findings that salt remains the most cost effective material to use as a de-icing agent during inclement weather. Most of the alternatives involve the use of abrasives or chloride based chemicals and are relatively costly compared to salt. For example, we recently paid $65 per ton for salt. Based on the Ohio State University study noted above, the present cost per ton for “CMA” is $650 by comparison. Last year we used 195 tons of salt, valued at $12,675. If we had used 195 tons of “CMA”, the cost would have been $126,750, or an additional $114,000.
While cost effectiveness is not the only consideration relative to the use of salt substitutes, based on information we have found, it is too early to conclude that environmental benefits are sufficient to offset the significant greater cost. The State of Oregon uses salt substitutes at higher costs. Oregon is a “no salt” state by legislation. While officials there believe that the environmental benefits justify the greater costs, we have been unable to find studies comparing the indirect costs. Studies note that Oregon uses relatively high quantities of de-icing materials other than salt, with accompanying environmental benefits. Data quantifying the actual costs are not readily available.
While the product known as “CMA” is available in commercial quantities, we likely would have transportation costs higher than those for obtaining salt if we were to start using this alternative. We did not include such possible additional costs in the cited $650 per ton for “CMA”.
We have and will continue to monitor alternative de-icing materials, and will make changes as appropriate.
1. BioCycle World Magazine article (p. 3).