Balancing Safety, Cost, and Environmental Impacts

A policy or plan for your site provides guidance to staff or contractors working on the site. It should outline responsibilities, procedures, and expectations for snow and ice removal.

A policy or contract should indicate the level of service, in other words, how clear that surface needs to be and by when. Getting to bare pavement usually takes more salt. Prioritize service areas for plowing and define where bare pavement is needed and where plowing alone is adequate. Identify areas that can be closed off for winter, areas where snow can be stored, and an area where salt will be stored on-site if needed. Consider adding caution signs for areas that are difficult to maintain such as steps.

Meet with staff or contractors to go over site plans and snow and salt storage areas. If possible, snow storage areas should be on the down slope end of paved surfaces so melting snow will not run off and refreeze on the pavement, resulting in slippery surfaces. If salt will be stored on-site, identify the storage area for granular and/or liquids and that it will meet state and local requirements such as being on an impervious surface and covered, or having double-walled tanks or secondary containment for liquids. Make sure that drainage does not go through a salt storage area or that salty water will not run out of the salt storage area.

A map of the property can be used to define your service areas and level of service if it differs throughout the property and to note storage areas. The policy should also define triggers for the start of snow and ice removal operations, usually based on forecasts, snow accumulation or freezing conditions, but should also reference freezing rain conditions.

Before the winter season, identify areas where roof drainage is directed over paved surfaces or gutters are leaking onto a sidewalk. These areas are prone to direct meltwater onto your sidewalks and parking lots that may require salt application due to ice build-up. Look for ways to direct drainage into vegetated areas or limit the amount of pavement exposed to the drainage. Repair low spots that result in ponding and slippery areas in winter. Each winter, take time to observe where these problem areas are, what is causing the problem, and if there is a way to improve them. 

Model snow and ice contracts and example policies are available for use by property managers and owners (see City of Edina, Help Protect Our Water). There are several types of contracts used with contractors:

• Seasonal (fixed feet) contract — client pays a fixed amount for the entire winter season.
• Per-push (per-event) contract — client pays each time the contractor performs service.
• Per-inch contract — price varies based on snowfall depth, often using tiers.
• Time and materials/hourly contract- client pays for actual labor, equipment, materials and deicing products used.
• Retainer or standby contract — owner pays retainer to reserve contractor availability with additional charges for services performed.
• Hybrid contracts — combination of 1-3+ per application salting, per inch charges above a cap, hourly loader work for snow hauling or time and materials for extraordinary events.

Make sure the contract language does not include charges for work based on salt use. Time and materials contracts encourage overuse of salt. Contractors should be paid to conduct follow-up visits and only apply salt if needed. The Snow and Ice Management Association (SIMA) offers guidance for creating a request for proposal (RFP). The Smart Salt Collaborative and The Conservation Foundation have also created a helpful guide for property managers that covers what to include in your RFP as well as information on smart salting practices, storage and identifying problem areas. 

Staff and contractors trained in snow and ice best management practices are more aware of best maintenance practices and chemical products and equipment that can provide more efficient and effective snow and ice removal and prevention. As a property manager or owner, there are some training courses available to you. If your own staff are doing the snow and ice maintenance work, find a local or online certification class that at least one staff member can attend. When hiring contractors, if possible, choose a contractor that has been trained and certified. 

Several state agencies and organizations have training certification programs. Hiring a New Hampshire Green SnowPro certified contractor provides limited liability protection for the business owner or lessee. Wisconsin SaltWise, Illinois Smart Salt Certified and other programs also offer contractor training. Check with your state environmental agency to see if there is a program in your area.

A publication from the New Hampshire Department of Environmental Services, Snow and Ice Removal Tips for the Business Owner, lists advantages of hiring a trained and certified contractor that is using best management practices:

• Increase the efficiency of removing snow and ice while ultimately decreasing the amount of salt that is applied to the parking areas and sidewalks that they manage.
• Save the business owner money through reduced salt use and fewer repair costs associated with damage to infrastructure caused by the caustic nature of salt.
• Reduce impacts on the surrounding environment by protecting groundwater and nearby streams, ponds, and lakes from chloride contamination from runoff that originates from parking lots, sidewalks and other areas treated with salt.
• Minimize the salt and sand that is often tracked into lobbies and offices at one’s facility. 
• Protect the landscape plantings (such as trees, shrubs, and grass) and soil adjacent to parking areas and sidewalks.

The publication also provides a list of questions you can ask your contractor to determine if they are using good winter maintenance practices as well as things you as a property or business owner or managers can do to improve winter maintenance and reduce salt use.

Below are some resources to help you find a contractor that will use practices that minimize salt use. Look for a certified contractor. Although certification doesn’t guarantee they will use all best practices, the contractor will be aware of them and likely recognize the value of using them.

Remove snow as soon as possible to limit the amount of compaction from tires and foot traffic. Shovel, blow, sweep, or plow snow off paved surfaces before using salt. Salt use will be reduced, and it may not be needed in some areas. Investing in equipment that removes snow down to pavement better.

Choose the right deicer for the weather conditions. The most common deicer, sodium chloride, works best between 32°F and 15°F. In colder temperatures, a blend containing calcium or magnesium chloride can work down to about 0°F. In colder temperatures, use sand or other abrasives for traction. Be sure to read the label for the chemical compound type and temperature conditions. See the Pavement Temperatures and Effects for more information.

Using liquid deicers can reduce salt use. Liquid sodium chloride, or brine, is only about 23% salt, the rest is water. Use liquids or allow contractors to use liquids on your site. They are very effective before the storm (anti-icing) to prevent the ice from bonding to the pavement and can be used to prewet granular salt to speed up the melting and keep it from bouncing off the pavement onto the vegetation. Liquids can also be used after the storm. This is often referred to as direct liquid application or DLA. With liquids, the salt may not be visible and there will be no crunch of salt beneath your feet. This doesn’t mean more salt is needed. It takes time to get acclimated to using liquids, but bare pavement can be achieved quicker, using less salt, with less salt tracked into the building. Liquids use also can reduce damage to adjacent lawns or other vegetation, saving money in repairs.

Calibration is the process of determining how much material is applied at each setting. Almost any type of equipment, from a hand spreader to a plow truck, can be calibrated. Equipment for granular materials and liquids should be calibrated. Calibrate deicer application equipment before each season for each type of deicer planned for use. Example calibration forms can be found in the MPCA Smart Salting for Parking Lots and Sidewalks Manual. Many videos on how to calibrate can be found online.

Deicer application rates are dependent on pavement temperatures, temperature trends, precipitation type, deicer type, and how much snow or ice is left after manual removal. Application rate charts such as one found in the MPCA Smart Salting for Parking Lots and Sidewalks (PDF) or Wisconsin SaltWise manual can be used or make your own chart. The salt crystals will be about 2-3 inches apart — not overlapping or piled up. More may be needed if there is a lot of snow or ice remaining after plowing or shoveling. Sweep up any salt that was over-applied and reuse it. See Application Rates for more information.

For building entrances, store salt in a dry area indoors — if possible — or covered on a paved surface. A covered five-gallon bucket or other container with a secure lid works well. Label your storage container with directions on salt use and keep a cup — or better yet a hand spreader or shaker — with your salt. Scoops are commonly used, but it is difficult to spread salt evenly and in smaller amounts with a scoop. For storage of salt in bulk, keep salt well-covered and on an impervious surface. Make sure melting snow or winter rain does not drain toward the salt storage area.

If you can get by without bare pavement or for colder temperatures, use an abrasive material such as sand. Sand will provide traction on the ice, but it will not melt the ice. You may also use sand only on lesser used sidewalks and walking paths to limit salt use. Other abrasives such as chicken grit, kitty litter, or cherry stone also provide traction. Once the snow event is over and icy conditions are resolved, abrasives can be swept up and reused.

Non-chloride deicers — such as acetates and formates — and additives like beet juice are also available. They work at varying temperatures and many are mixed with a chloride deicer. These are more expensive than rock salt but reduce chloride use.

Documenting weather conditions and winter maintenance operations can help track what works best under different conditions allowing for adjustment of practices to improve efficiency and effectiveness. You or your contractor should be keeping accurate records and documenting conditions and actions such as weather conditions, pavement temperature and condition, date and timing of winter operations, deicer application quantities, type of deicer, as well as staff training and calibration dates. Photos can be very helpful too. Thorough documentation can help reduce liability concerns.