The impact of road salt on our environment By Ted Butler Many Canadian municipalities use road salts (and other chemicals) on our streets and sidewalks for their de-icing and/or anti-icing capabilities.
R
oad salt is an important tool currently being used in the annual battle to keep our roads safe during
Salt also completely loses its
internal water-conducting system and
effectiveness as a de-icing agent
can lead to the death of the plant.
when the ambient temperature reaches -13 to -15 degrees Celsius.
our cold Canadian months. Many
Other de-icing sprays can lose
Canadian municipalities use road
their effectiveness at temperatures
salts (and other chemicals) on our
between -7 or -9 degrees Celsius,
streets and sidewalks for their de-
which means applying them to the
icing and/or anti-icing capabilities.
roads below these temperatures is
The question is, do we use too much salt and chemicals on our roads?
futile.
Possible environmentally friendly solutions Cheese Brine Some roads in Wisconsin are treated with cheese brine from local dairy companies. The salt baths which are used in making cheeses like
on our environment, and do they
Magnesium chloride (MgCl2)
contaminate our streams and rivers?
Magnesium chloride is the name
costs money to have it treated off site.
of a chemical compound, the
The dairies dispose it for free and the
formula MgCl 2 and its various
county acquires it for free – a win-win,
hydrates MgCl 2(H 2O)x. These salts
according to authorities.
Are they having a negative impact
To answer these questions, let’s have a look at two of the most popular de-icing formulas being used today…
mozzarella or provolone need to be discarded as a waste product, and it
are typical ionic halides which are highly soluble in water. Hydrated
Beet Wastewater
Sodium Chloride - NaCl.
magnesium chloride can be
Commonly known as salt, sodium
magnesium chloride is made from
chloride is an ionic compound
the solar evaporation of seawater.
with the chemical formula of
Hydrated magnesium chloride is
NaCl. Sodium chloride is mostly
the form most readily available.
responsible for the salinity of
Chloride (Cl-) and magnesium
seawater. Large quantities of
(Mg+2) are both essential nutrients
sodium chloride are also used in
important for normal plant growth,
many industrial processes and
but too much of either nutrient may
NaCl is already being detected in
harm a plant. High concentrations of
Pickle Juice
our ground water. The measured
MgCl 2 ions in the soil may be toxic
Pickle brine is as effective as salt. It
amounts of NaCl is expected to
or change water relationships and
can melt ice at temperatures as low as
increase over time which will
the plant cannot easily accumulate
-6°F or -21°C. It doesn’t smell great,
eventually contaminate drinking
water and nutrients. Once inside the
but it’s cheaper and deposits less
water.
plant, chloride moves through the
chloride into the environment than
8
extracted from seawater. Some
This is an organic-based liquid that contains processed beet molasses. It’s been used by over 200 agencies in the USA. When it’s combined with the traditional de-icing agent of salt, the beet product freezes at a lower temperature than a pure salt brine so it can be used in lower temperatures.
ISSUE 2 – 2019 | SNOW MANAGER
