Using GIS to estimate salt route tonnage figures

​Every year the city of Chicago and its surrounding suburbs receive a
significant amount of snowfall from December to March. With large
amounts of snowfall comes the need to keep roads free of snow and ice so
that they can remain safe and drivable. Although some suburban
communities have experimented with sand as an applicant for better
traction, almost all communities use salt to melt snow and ice, the City
of Park Ridge is no exception.

Although the city provides their residents with an excellent service
of snow and ice removal, this service tends to consume a large volume of
salt. In addition, because snow can fall at an alarming rate, it is a
tough for the Public Works Department to track how much salt they are
using in comparison with how much they estimated for the year. In order
to help with this issue, the Geographic Information System (GIS)
Department provided the Public Works Department with accurate street
lengths for all salting routes within the city based on an existing
digital street file. The GIS department also provided estimates for all
intersections that get salted along established salting routes and all
major intersections around school boundaries.

The idea of collecting the linear street lengths for all routes and
route intersections was to have a benchmark for what amount of salt
would be needed to cover these routes in the event of a two-inch
snowfall. Although all storms are not created equal, having an
estimated figure in comparison to the real amount of salt used would not
only help the Public Works Department keep track of each ton of salt
dispersed, it would also help with them with future predictions of how
much salt needs to be ordered. By understanding what amount of salt is
used in comparison to what is predicted, the Public Works Department
could be more prepared for the amount of salt they need to initially
order or re-order in the middle of a season. Having these figures could
also assist with the budgeting process when the Public Works Director is
asked to provide an estimated figure for future cost expenditures,
especially when salt prices are on the rise.

Although this a quick example, it is easy to see how combining the
forces of two different departments has allowed the Public Works
division to utilize the resources of data stored in GIS to gain more
control of their salting program. Additionally, the understanding of
what the GIS Department can provide along with what the Public Works
Department needs will help the two be prepared for the any changes that
are introduced to the existing program.