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
Click to watch
ACHD's winter maintenance video.
Street Service Policy
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.
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.
- 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
after a big storm, snow sometimes remains in the center lane of 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.
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.
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 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?
Anti-icers and de-icers have little or no impact on
Study of environmental effects of magnesium chloride in Colorado
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.
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.
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
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
“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