by Tina Grady Barbaccia

Salt has been the tried-and-true material when it comes to winter maintenance, but one of the latest trends in winter maintenance is a shift toward brine, along with other liquid deicers to make the salt more effective and economical.

The State of Maine has been pioneering use of treated salt, Vermont has been trying it and New Jersey is starting to take a look at it, says David Wood, president of Sears Ecological Applications Co. (SEACO). Other areas, such Illinois’ McHenry County, has also experimented with treated salt and manufacturing its own brine. “The drivers here are environmental concerns, cost and performance,” Wood points out.

With tightening environmental regulations and the current weak economic milieu, there is a need to stretch salt as far as it can go so use of advanced brine technology has become a critical part of winter maintenance.

This served as the impetus for the Maine Department of Transportation’s to conduct a treated salt study. According to the study, Maine DOT found that the combination of a treated salt and liquid deicer through onboard prewetting created the fastest and longest-lasting effect and the lowest cost, from both a fiscal and environmental standpoint. Treated salt usage represented about 30 to 35 percent product saving versus traditional untreated salt, and the untreated salt with additional onboard pre-wetting represented about a 40 to 50 percent savings versus untreated salt.

The purpose of the study was to observe the effectiveness of pre-treated salt and to understand how two different types of liquids, Ice-B-Gone and magnesium chloride, would work in the application. The methodology was having two adjacent interstate crews coordinate timing of applications while tracing various application rates of the different materials, with and without pre-wetting. The rest results were conducted using conventional with rock salt (dry and with liquid added), magnesium chloride (Mag) treated salt (dry and with additional liquid added) and brown treated salt (Ice B Gone) treated salt (dry and with additional liquid added).

Maine DOT’s initial trial of six different methods of applications of salt treated salt follows:

1. White Salt without liquid: Least effective method.
2. White Salt with onboard liquid: Marginally more effective that White Salt alone.
3. Blue Magnesium Salt without liquid: More effective than White Salt with or without liquid.
4. Blue Magnesium Salt with additional onboard liquid: More effective than Blue Mag salt without liquid.
5. Brown agricultural salt without liquid: More effective than Blue Mag salt without liquid.
6. Brown agricultural salt with additional onboard liquid: Most effective throughout duration of the trial.

The use of salt brine — a mixture of 23 percent salt and 77 percent water (the carrying capacity of slat in a water solution) — for melting snow and ice was developed in Europe. The mixture is sprayed directly on the road as an anti-icing agent. Although salt brine has the same melting characteristics of regular salt, because it is in brine form, it has the advantage of working immediately and doesn’t have the problem of “bounce and scatter” off the road because of its consistency, according to a study of salt brine use by the Vermont Agency of Transportation, Materials and Research Section. The agency found that brine was cost effective to produce, at about $0.10 per gallon. Additionally, other deicing chemicals can be mixed into the salt brine to lower the effective melting temperature.

During the study in which experimental test sections of Vermont interstates were treated with salt brine and salt brine mixtures, the agency found that it saved an average of 24 percent of material usage.

“Although the data sets were not as extensive as the research team initially thought, the research project was able to produce salt savings of approximately 30 percent and materials cost savings of approximately 30 percent and materials cost savings of approximately 24 percent during the first year of experimentation,” according to the Vermont DOT report. “If such a cost savings could be projected statewide, the potential savings would be almost $1 million annually.”

The research team agreed that there is potential for more salt and cost savings as staff becomes more experienced with the technology.

“Through the use of salt brine, brine blends and brine technology, the research project was able to produce safer, better winter roads at [a] lower cost, [and use] less salt and less sand,” the agency says in the report.

A ceramic rubber blade originally developed in Germany has been brought to the United States. The blade is making waves in the winter maintenance community because of its ability to keep from damaging raised pavement markers.A new rubber blade integrated with ceramic is making waves in the winter maintenance community.

Editor’s Note: This coverage is a continuation from the June 2011 cover story in Better Roads on the latest in winter maintenance technology.

Developed 20 years ago in Germany, the blade was just introduced to the U.S. market two years ago for testing. Being marketed as the Küper GK-5, transportation agency personnel say this blade makes damage of raised pavement markers on roads and highways almost nonexistent, which can prove costly for Departments of Transportation. Damage to the markers can also pose safety issues because it can strip the markers of retroreflectivity, explains Wilf Nixon, Ph.D., P.E., professor of civil and environmental engineering with University of Iowa and a top researcher on winter maintenance.

“It’s a rubber blade with ceramic in it,” Nixon says. “The rubber won’t damage raised pavement markers. Straight rubber curls back under a plow, but with ceramic as part of it, there is stiffness so the rubber will not fold under the full weight of the plow and it cleans the road better.”

Typical rubber face plates have no rigidity, and they are very effective in wet, slushy snow. “It works life a squeegee,” Nixon says. The blade has ceramic cylinders with a steel neck in the top one-third of the blade, which mounts to the plow blade without additional mounting hardware. “The ceramic-rubber blade mix reduces friction,” explains Nixon. “A straight rubber blade going down the road is essentially burning itself up.”

Although the blade is being revered as cutting-edge technology (pun intended), there are situations where it would not be applicable. “It doesn’t make sense in very cold areas with hard-packed snow, Nixon says the blade was field tested this past winter in the city of Redmond, Wash., and then tested by the Tennessee Department of Transportation. Both groups were very pleased with the lack of damage to their pavement markers as well as the performance and long service life of the GK5.

Why are cutting edges of such significance in the winter maintenance community? Nixon says improving removal of snow and ice is critical to a reduction in resources used and performing winter maintenance more effectively. “If you can get longer life and better overall performance from a blade, it all adds up from a bean counter standpoint.” — by Tina Grady Barbaccia, Executive Editor

More technological advancements are becoming available to today’s snowfighters that help lower user costs, allow for more efficient operations, reduce environmental impact, increase safety and enhance commerce.

How do you know what to look at when starting a winter maintenance program? What should you look for in a vendor and what kind of support systems are out there to help you with your program?

Anti-icing programs are emerging as a mainstay of any winter maintenance program, says Sean M. Riley with Cargill Deicing Technology. However, understanding what to look at when developing an anti-icing system is important. When considering a deicing program, Riley says, the following should be considered:

• mechanical versus non-mechanical;
• installation, maintenance and operation costs;
• single-purposed versus multi-purposed; and
• recommended liquids.

When looking at starting an anti-icing program, Riley says, the following should be considered:

• production volumes,
• concentration accuracy,
• construction materials,
• cleanout method, and
• total cost of ownership.

Once you’ve decided on which type or types of programs, the products and vendors that will be used in the anti-icing or deicing program need to be assessed. Here’s what you should ask about the products, Riley says:

• formulate an accurate expectation on payback,
• create a method to effectively measure performance,
• train my employees on proper usage procedures,
• build a consensus and obtain buy-in from decision makers, and
• educate the public as to how we are saving money and reducing environmental impact.

Here’s what you should ask vendors when developing the program:

• Is the vendor proven, reliable and experienced?
• Are they a specialized or a comprehensive provider?
• Is the vendor resourceful?
• Are they a producer or reliant on the open market?
• Can they provide post sale support?
• Are they a partner or just a vendor?

Click here for a downloadble PDF of the presentation, “Reducing Costs and Environmental Impact Through Technology and Education,” given at the American Public Works Association (APWA) and Pacific Northwest Snowfighers Snow Conference, held in mid-April and attended by Better Roads

The presentation was given by Cargill at the American Public Works Association (APWA) & Pacific Northwest Snowfighters Snow Conference held in mid-April in Spokane, Wash.