There are three fundamental snow and ice control strategies in winter maintenance: anti-icing, deicing, and snow removal. Each method seeks to address the safety issues that result from the buildup of snow and ice on pavement.
Anti-icing and deicing use many of the same types of equipment and materials, but where they differ is when and how they are used. Anti-icing is a preventive measure that inhibits snow and ice from bonding to the pavement, whereas deicing is a reactive measure to break an established ice-to-pavement bond.
Snowfighters armed with the appropriate tools to execute each of these strategies are optimally prepared to expedite service objectives and gain a competitive edge when a storm hits.
PREVENTIVE STEPS
To achieve optimum outcomes, anti-icing requires judgment in assessing a variety of real-time conditions to determine the preferred approach. Factors impacting such decisions include pavement surface temperature, the amount of moisture (both present and anticipated), the type of deicing material used, cycle times, and the anticipated amount of sunlight and traffic during the event.
ANTI-ICING 101
Although anti-icing can be performed using various materials and equipment, there are a few best practices to follow to ensure a more effective snow removal no matter the equipment used.
- Employ a proactive strategy: typically executed up to 48 hours in advance or at the onset of a storm, as long as rain is not in the forecast.
- Employ a bottom-up strategy: to inhibit compacted snow and ice from forming a strong bond with the pavement.
- A “best practice” is to use a light application of a liquid deicer (an estimated 18 to 35 gal per acre, but should be adjusted based on conditions) applied directly to the bare pavement surface; however, pre-wet solids can also be used when necessary.
- New studies demonstrate that under certain conditions during a storm, Direct Liquid Application (DLA) of a deicer can be both an effective and efficient strategy as long as a strong bond has not formed.
- Do not apply on top of compacted snow or ice or ahead of rain, sleet, or high winds.
BENEFITS OF ANTI-ICING
Acting as a preventive solution, anti-icing has its benefits, such as:
- Expands operational timeframe to achieve service goals.
- As a preventive strategy provides expedited safety objectives at a lower cost.
- Reduces salt damage to property and landscaping when applied correctly.
- Reduces time and labor required to achieve performance goals.
- “Anti-icing requires about 1/4 the material and 1/10 the overall cost of deicing. It is the most cost effective and environmentally safe practice in winter maintenance,” according to the “Winter Parking Lot and Sidewalk Maintenance Manual,” 2010 Minnesota PCA, MLTAP and Fortin Consulting.
PRE-WET SALT DEICING
The more common (reactive) approach to snow and ice control is to wait until an inch or more of snow accumulates on the pavement before starting to plow and treat the surface with deicers or abrasives. This approach often results in compacted snow bonding to the pavement surface. When this occurs, deicing measures are called for, requiring substantially more material to undercut the ice pack and weaken the bond to allow for removal.
“Because deicing is reactionary … as a result of its inherent delay, it often provides less safety, at higher cost, than anti-icing. Nonetheless, the reactive technique of deicing will remain important for snow and ice control, as there will always be lower priority service levels that preclude preventive operations,” according to the “Manual of Practice for an Effective Anti-Icing Program, A Guide for Highway Winter Maintenance Personnel,” FHA 1996.DEICING 101
Before beginning deicing operations, keep the following steps and techniques in mind:
Employ a reactive strategy: Begin during or after a storm.
Employ a top-down application to penetrate and break a compacted snow or ice-to-pavement bond to facilitate plowing.
A “best practice” is to use a liquid deicer to pre-wet rock salt in the auger or chute just prior to spreading.
BENEFITS OF PRE-WET
Using pre-wet salt to break up snow and ice comes with its benefits, such as:
- Less salt bounces off surface, conserving material and reducing environmental impacts.
- “Pre-wetting salt with brine or other liquid chemicals has proven to reduce application rates by 20-30%,” according to the “Innovative Environmental Management of Winter Salt Runoff Problems at INDOT Yards,” 2004 Joint Transportation Research Program Study Purdue University, INDOT, FHA
- Pre-wetting with salt brine jumpstarts the brining process and accelerates performance, while solid deicers must first form a liquid to work.
- Pre-wetting with one of the exothermic chlorides (calcium chloride or magnesium chloride) will also enable the salt to work effectively at a lower temperature.
- Reduces time and labor required to achieve the desired performance goals.
KEYS TO SUCCESS
Before embarking on a snow removal business endeavor—and even for those who are already in the business—consider the tips below to ensure a successful snow removal.
- Obtain the right equipment and materials to execute each of these operations and monitor/control application rates.
- Provide your crew with comprehensive training on best management practices for these strategies.
- Obtain accurate, advance, and real-time information relative to the conditions of a given storm.
- Synchronize the use of these tools, resources, and information to determine the best strategies and timing of operations to achieve optimum performance outcomes.
- The snowfighter who masters these elements can save thousands of dollars during the course of a season and achieve the competitive edge needed to grow their business.
FOR MORE INFORMATION
The information from this article was provided by SnowEx. Find more tips for snow removal, visit www.snowexproducts.com.
