Scott Frisbie
Cloverdale Superintendent

Brenda Morris
Adams Superintendent
Tell Us

Winter Street Service

Preventing problems rather than responding after-the-fact to storms best describes ACHD's approach to winter weather. Fighting ice on the pavement is the primary focus and explains the heavy reliance on anti-icing treatments with magnesium chloride.

Sand, rock salt and plowing are also facets of ACHD's response, employed as required by conditions.

Ada County gets around 21 inches of snowfall annually, usually in the form of several small storms during the season. More often than not, snow melts quickly as daytime temperatures hover at or above freezing. As overnight temperatures drop, the roadways can become icy from rain and snowmelt, creating potentially slippery conditions from November through March.

Click to watch ACHD's winter maintenance video.

 Winter Street Service Policy

Snow Flyer imageACHD generally favors anti-icing, sanding and salting over plowing as the most effective treatment for the county's normal winter conditions. Sand and salt (in targeted applications) are applied when extra traction is needed. When snow accumulates, plowing is done before more anti-icing material is applied.

Priority System

Even with a large fleet of vehicles, the District must use a priority system to ensure that the most-used or most-critical roads get first attention.

 Snow Plow

Priorities for Anti-icing, Sanding, Salting and Plowing:

  • Arterial and collector roads
  • Major intersections
  • Overpasses and bridges
  • Railroad crossings
  • Areas around hospitals and fire stations
  • School and railroad crossings
  • Streets with grades over 6 percent

Although residential streets are important, they have lower speeds and lower traffic volumes. Given the amount of personnel and equipment available, ACHD must focus its response to yield the biggest benefit. Snow will melt off by the time District crews could practically get onto neighborhood streets.

Following plowing after a big storm, snow sometimes remains in the center lane of the roads. The removal of this snow is accomplished during non-peak hours and disposed of at predetermined sites. This type of work may take long periods of time, and due to the high cost of equipment and labor, the Ada County Highway District does not remove all accumulations of snowfall from all roadways.

Sidewalks and Parking LotsSnow Flyer 2016

When it snows residents have a job too. Keeping the sidewalk in front of your home or business clear of snow and ice is required by local and state codes. Click to learn more.  

What not to do snow flyer image 1What not to do snow flyer image 2


More on Anti-Icing

When below freezing weather is eminent, ACHD applies magnesium chloride on priority areas. ACHD uses the least amount of anti-icing liquid possible. The application helps prevent ice from forming on the roadway, and greatly reduces black ice and slippery conditions. It can also melt existing ice on streets but this after-the-fact treatment is not nearly as effective as pre-treatments. In downtown Boise, ACHD uses road salt, which melts snow and ice and creates less of a mess on sidewalks than the anti-icer. It is also better for the environment than sand, which will runoff into storm drains that directly access the Boise River.

Anti-Icing Truck

Anti-icing publications from the Federal Highway Administration:

Saving Money and the Environment in Oregon

Anti-Icing Saves Time and Money in Colorado

How Do Anti-Icing Methods Work?


Colorado DOT fact sheet: 

Anti-icers and de-icers have little or no impact on environment

Study of environmental effects of magnesium chloride in Colorado


What about my car?

While ACHD buys magnesium chloride and rock salt treated with corrosion inhibitors, it is still a good idea to wash your car often in the winter months to prevent potential corrosion.

Removing Sand

Sweeping of roadway sand will begin as soon as conditions allow. ACHD conducts a dust abatement sweeping program throughout the winter months. Once the priority routes have been swept, operations concentrate on all remaining roadways.

Heavy Snow Conditions

During periods of unusually heavy snowfall, ACHD has agreements with local contractors to help with plowing. This reduces our equipment inventory requirement thus reducing our overhead costs for winter maintenance.

ACHD does not specifically budget a large amount of funds for snow removal. Click here for a snow removal video  When we have severe weather and have to hire contractors, we adjust our budget at mid-year (in April) to cover the additional costs. The budgeted funds that are spent in the summer such as asphalt mix, gravel, liquid asphalt, and others are reduced accordingly.

“I would like to send high praise to all the dedicated individuals in the maintenance department concerning the grand performance seen during the past winter season. Keeping the roadways, hillside streets and bridges safe during highly inclement conditions is an enormous and difficult task. I, for one, was not inconvenienced nor hindered in my daily travels. The logistics, planning, good equipment and execution were truly top shelf.”

John Robert Meagher
Boise, Idaho