7. PW - Calcium Chloride Application
Staff Report
Date of Meeting: 5/4/2022
For: Honorable Mayor and Council
From: Charles Fischer – Director of Public Works
Subject: Calcium Chloride Application
Background:
The gravel roads in Scandia have been receiving applications of Calcium Chloride for many years
to stabilize the road and control dust from vehicle traffic. Public Works has coordinated the
applications through vendors at specific times of the year with the most important application
taking place mid-Spring. Calcium Chloride applications are non-toxic, trap moisture from the air,
and does not evaporate easily making it an ideal dust suppressant. One major drawback to
Calcium Chloride is the corrosive nature to metal surfaces. Typically, one application per year
has been done but during dry seasons the southern gravel roads (185th St. N., Oakgreen Ave. N.,
and Old Marine Trail N.) have received a second application in the later portion of the summer.
When the City applies the product to the entire road surface complaints ha ve come from
residents of vehicles and trailers rusting much faster than if no Calcium Chloride were to be
applied to the roadway. One the other side of the spectrum the City has received complaints
that not enough applications are completed or that they are not timed appropriately and health
concerns over dust inhalation have been reported. Public Works favors the applications of
Calcium Chloride for the reasons of road surface stabilization and dust control. Calcium Chloride
helps prolong the loss of dust and fine particles. The loss of fine particles contributes to the loss
of larger aggregate and gravel roads deteriorate faster leading to the need for additional
grading and gravel to be added to the roads. The City includes the roads of the Cedar Cliff area
within the quotes. If treatment is requested by the Cedar Cliff residents, the city charges for this
service.
Proposal:
This year Public Works is proposing to apply one application to all gravel roads highlighted on
the map and have the ability to apply a second application later in the season to only areas of
concern for dust and road surface instability.
Fiscal Impact:
Funding for the applications will come out of the Public Works General Fund and have been
factored into the total Contractual Road Maintenance Repair line item along with other
necessary maintenance or repairs required in 2022. Quotes have been received from two
vendors: Knife River and Northern Salt Inc. Knife River has set their cost to $1.34 per gallon of
product applied and Northern Salt Inc. has set their cost to $1.322 per gallon applied. Total cost
for each vendors application has a marginal difference. A full application through Knife River
will cost $22,780.00 and a full application through Northern Salt Inc. will cost $22,474.00. A
second application will vary in cost but typically has been half the amount of the initial full
application.
Options:
1.) Award Calcium Chloride application for dust control to Northern Salt Inc. at a cost of
$1.322 per gallon totaling $22,474.00 for one full application and second application
later in the season to areas of concern for dust and road surface instability.
2.) Award Calcium Chloride application for dust control to Knife River at a cost of $1.34 per
gallon totaling $22,780.00 for one full application and second application later in the
season to areas of concern for dust and road surface instability.
3.) Do not apply Calcium Chloride on gravel roads.
Recommendation:
Option 1