Winter De-icing
Homeowner’s Guide to Stormwater Management Philadelphia Water Department
As snow piles up in the winter, we oftentimes turn to
salt to melt snow
and ice. Salt, however, causes adverse environmental impacts, especially on our
streams and rivers, our drinking water source in Philadelphia. Excess salt can
saturate and destroy a soil’s natural structure and result in more erosion to
our waterways. High concentrations of salt can damage and kill vegetation. Salt
poses the greatest danger to fresh water ecosystems and fish. Studies in New
York have shown that as salt concentrations increase in a stream, bio-
diversity decreases. Excess salt can seep into groundwater and stormwater
runoff. Effective ice control can help prevent excess salt runoff to our
waterways.
De-icing in the Winter
There are many alternatives to salt including potassium chloride,
calcium chloride and magnesium chloride, corn processing byproducts, and
calcium magnesium acetate (CMA). Most can be found in your local hardware
stores under various trade names, so check the labels for chemical content.
While these alternatives can be spread in a dry form or sprayed as
a liquid,
their best use occurs when they are used with salt. They tend to increase the
efficiency of salt thereby reducing
the amount that needs to be applied. When
over-applied, all chloride compounds can be harmful to the environment. Non-
chloride corn byproducts recycled from mills and breweries have been shown to
be effective de-icers as well. While they are often advertised as organic or
natural, they can have extremely high phosphorus content, a major water
pollutant. Numerous studies have shown calcium magnesium acetate (CMA) to be
the most environmentally benign de-icer. Many northern states use CMA on roads
in sensitive areas (wetlands, endangered species’ habitat, drinking water
supply, etc.). A couple of disadvantages with CMA however, is that it does not
work
well below 25° Fahrenheit and it is the most expensive de-icer. Because
all de-icers can be harmful to the environment when applied in excess, the best
strategy is to reduce the use of these chemicals as much as possible.
•
The first line of defense should simply be to shovel sidewalks and
pathways to keep them clear and to prevent ice from forming. Also, consider
that salt and de-icers are not effective when more than 3 inches of snow have
accumulated.
•
Consider the temperature. Salt and calcium magnesium acetate (CMA) have
a much slower effect on melting snow and ice at temperatures below 25°
Fahrenheit.
•
Track winter weather and only use salt and de-icers when a storm is
about to come through. If a winter storm does not occur, sweep up any unused
material, store, and reuse for the next big storm.
•
Apply de-icing products discriminately, focusing on high-
use areas and
slopes where traction is critical. Apply the least amount necessary to get the
job done. This will save money in product costs and will also help minimize
property damage to paved surfaces, vehicles, and vegetation.
•
Reduce salt and other chemicals by adding sand for traction.
•
Become familiar with various de-icing products and wetting agents such
as magnesium chloride and calcium chloride, which can improve the effectiveness
of salt and reduce the amount needed.
•
If you observe ongoing issues of ineffective ice management or examples
of poor application, such as excess piles of road salt left to disperse, share
your concerns with the property manager of your residence or business, or with
the City of Philadelphia Streets Department. The Streets Department Hotline is
215-686-5560 and their website is www.phila.gov/ streets.
•
Plant native vegetation that is salt tolerant in stormwater drainage
swales and ponds that may receive salt-laden runoff. Not only will these native
species have a greater chance for survival, but they will continue to act as an
effective buffer for our local waterways.
•
Store salt and other products on an impervious (impenetrable) surface,
such as a basement floor, to prevent ground contamination. Also store products
in a dry, covered area to prevent stormwater runoff.
Thanks a lot for sharing this information. Salt is indeed the most inexpensive and effective way of de-icing the road. But it has a negative effect in the environment. So I guess this so-called CMA is a great alternative to the traditional salt.
ReplyDeleteEastCoastSalt.com
Seems like things would be better off channeling the waterflow to avoid major ice build up. Sounds like something for construction site cleanup crews to consider!
ReplyDelete-Jack