Winter Storm Operations

Each winter storm event is unique. Therefore, the judgment of the superintendent of highways often governs the quantities and type of applications used to control snow and ice. Public safety is always our top priority. It is the intent of the Highway Department to use the minimum de-icing or anti-icing material needed to restore safe travel conditions as soon as possible following the termination of winter storms.

There are many variables affecting winter maintenance operations such as type of precipitation, air and pavement temperature, traffic volume, wind, time of day, and even the day of the week. Type and volume of traffic and road gradient are the primary factors in determining the order of winter maintenance service. Providing bare dry travel surfaces during a winter storm event is not practical and therefore not expected.

Frozen precipitation including sleet and the buildup of ice caused by freezing rain are special situations. When a changeover from snow or sleet to freezing rain is predicted or anticipated, snow and/or sleet is left on the pavement to capture the freezing rain thereby preventing a glare ice situation which without question is the most treacherous condition that occurs on highways. Treatment includes applications of salt as needed throughout the storm, although heavy rain tends to wash off applied salt or sand, making it difficult to keep the pavement ice-free.

Plowing Operations

Plowing operations are generally initiated after 2 to 4 inches of snow have fallen and may continue until the storm has concluded.  It is expected that each plow route will take four hours or less to complete. Currently, 18 six-wheel dump trucks, three 10-wheel dump trucks, two three-ton dump trucks, and three loaders are used for plowing the 176 miles of highway and various municipal parking lots. Three trackless sidewalk plows are used for maintaining 40 miles of sidewalk. The Town does not plow State or County Roads but we do maintain sidewalks along State and County Roads.

Unfortunately, there is no way to prevent depositing snow in previously cleaned driveways or walkways except to leave a hazardous mound of snow. With thousands of driveways of all sizes and descriptions along our roadways, it is impossible to clear these individual drives.

Materials Used

Snow removal and ice control usually requires the timely application of either chemicals, abrasives, or a chemical-abrasive mixture to roadway surfaces in combination with aggressive snow plowing operations. Choice of material is dependent upon the weather and road conditions.  Occasionally conditions such as low temperatures do not require material applications. Materials available include the following:

• Sodium Chloride:  The use of sodium chloride (common salt) combined with snow plowing is the most effective, most economical, and safest snow and ice control method currently available. Salt is most effective for melting purposes at temperatures above 20 F, with reduced melting ability as the temperature drops. In general, the purpose of salt is to:
  • Reduce adherence of snow to the pavement
  • Keep the snow in a "mealy" condition and thereby permit nearly full removal by plowing
  • Prevent the formation of ice or snow ice (hard pack)
  Salt is not intended to take the place of snowplows. It is economically and environmentally unacceptable to attempt to melt snow accumulations that can be plowed.
• Calcium Chloride:  Calcium chloride is a chemical that melts ice at lower temperatures than sodium chloride. Liquid calcium chloride can be used to pre-wet solid sodium chloride to trigger the chemical reaction at low temperatures. The addition of liquid calcium chloride is also beneficial in retaining de-icing material on the roadway by increasing the adhesion of the material to the roadway.
• Abrasives:  Abrasives (sand and fine mineral aggregates) are used primarily for immediate traction on hills, curves, intersections, railroad crossings, and other areas to increase traction and minimize the use of salt.
• Liquid Magnesium Chloride:  Magnesium chloride with a refined corn carbohydrate derivative. This product has a lower effective melting point and excellent anti-bonding properties and is used for “Anti-Icing”. This allows us to obtain cleaner sidewalks after most events. It is approximately 75% less corrosive than “Salt Brine”.

Generally the Town of Bethlehem Highway Department applies sodium chloride pre-wet with a calcium chloride solution to the middle one-third of pavement width and on the high side of banked curves. Materials are applied early in the storm so that brine develops on the pavement and prevents build-up of packed snow. It takes much less de-icing chemical to remove compacted snow when the treatment is placed between the pavement and the snow layer than if it is placed on top of the snow. If snow continues and accumulates on the pavement, plowing will continue and additional chemical treatments will be made if compaction develops.

Sidewalks

Typically, plowing on sidewalks does not commence until accumulations are in excess of two inches. The longer it takes to clear a route, the greater the chances for the snow to become packed, turn to ice, etc. Property owners can assist by removing snow from the sidewalks after a storm.

After heavy snowfalls, the sidewalk machines will be equipped with snow blowers to widen out the sidewalk. It can take several days to clear the routes with a blower, but heavier accumulations necessitate the use of a blower to clear the full width of sidewalk.

Prior to some events we will apply an “Anti-Icing” liquid to help reduce the bonding of the snow or ice on higher volume sidewalks. This helps allow us to obtain cleaner sidewalks after an event.