CITY CLERK
Clause embodied in Report No. 8 of the Urban Environment and Development Committee, which was
before the Council of the City of Toronto at its meeting held on June 9, 10 and 11, 1999.
17
Road Salt Environmental Impact Study
and Reduction of Road Salt Use
(City Council on June 9, 10 and 11, 1999, struck out and referred this Clause to the Works Committee for further
consideration and the hearing of deputations, in accordance with the recommendation of the Works and Utilities
Committee embodied in the communication dated May 19, 1999, from the City Clerk.)
The Urban Environment and Development Committee recommends the adoption of the following report (April 28,
1999) from the Commissioner of Works and Emergency Services:
Purpose:
To respond to the request from City Council to consider the road salt motion that was before City Council on November
25, 26 and 27, 1998 and report thereon to Works and Utilities Committee.
Funding Sources, Financial Implications and Impact Statement:
Funds are available in the amount of $5,000 in the recommended 1999 Works and Emergency Services communications
budget for production of a brochure on the alternatives to road salting and their potential benefits to the environment.
Recommendations:
It is recommended that:
(1)the Commissioner of Works and Emergency Services report to your Committee following the publication of the
results of the Canadian Federal Government's research programme on the toxicity of road salt; and
(2)Works and Emergency Services staff prepare an information bulletin outlining possible alternatives to road salt,
including the costs and benefits, and make this information available to other major users of salt and public-at-large upon
request, and that the same information be made available:
(a)on the City's Internet website; and
(b)as part of the annual winter maintenance brochure prepared by Transportation Services.
Council Reference/Background/History:
City Council at its meeting held on November 25, 26 and 27, 1998, received for information, Clause No. 7 from the Works
and Utilities Committee Report No. 10 which included the following Motion:
"THAT staff report to the Works and Utilities Committee on a means of conducting a comprehensive road salt
environmental impact study; and
THAT the Committee endorse, in principle, that the City of Toronto work towards decreasing the amount of road salt used,
and finding new and less environmentally hazardous substances to use in place of road salt; and
THAT the Committee ask staff to advise on a public education campaign aimed at not only residents of Toronto, but also
major users of road salt, educating them on potential alternatives."
Discussion:
1.Road Salt Environmental Impact Assessment:
The impacts of road salt (or sodium chloride) on the natural and built environment are well known and have been widely
researched by Government, industry, and academia. Over the years, the use of road salt has been linked to damage to
vehicles, infrastructure and the environment.
(a)Previous Road Salt Impacts Studies in Toronto
In 1990, the Medical Officer of Health and Commissioner of Public Works for the former City of Toronto, prepared a
report on the "Use of Road Salt and Alternative De-Icing Methods" which was adopted and amended by Toronto City
Council at its meeting held on October 22, 23, and 24, 1990 (Clause No. 17 of Report No. 14, City Services Committee,
1990). Also in 1990, the Commissioner of Transportation for the Municipality of Metropolitan Toronto prepared a report
on "De-icing Agents on Metropolitan Roads". Both reports are attached and contain a comprehensive review of studies and
findings on the negative impacts of road salt on the environment, particularly water and soil quality, vehicles and
infrastructure.
The link between the City's use of road salt and its effect on vegetation and lake water quality is difficult to ascertain. With
respect to lake water quality, the Commissioner of Transportation's report cited findings of the National Water Research
Institute that chloride levels in Lake Ontario had decreased to the present level of 26 milligrams per litre from a high of 28
milligrams per litre in 1974. The report also stated that the primary sources of chlorides in Lake Ontario are from industry
and from natural salt mines under the lower portion of Lake Huron and the Detroit River area. A report prepared by the U.
S. Geological Survey indicated that ice control accounted for only 33% of the total salt consumed in the United States in
1996. The chemical industry consumes approximately 42% of the salt produced.
With respect to the City's use of road salt and its impact on vegetation, the former Toronto City Council received a report
on February 4, 1991 prepared by the Commissioner of Parks and Recreation Department for the City of Toronto on the
"Effect of Salt on Trees and Other Vegetation in Toronto" (Clause No. 44 of Report No. 2, City Services Committee,
1991). This report, which is attached, cited numerous negative symptoms observed on Toronto trees but could not attribute
these symptoms solely to road salt. The report stated that the impact of road salt on trees in the urban environment is
difficult to quantify due to the stress caused by many other factors such as other airborne pollutants, soil compaction, acid
rain, lack of absorption area and high temperatures of air and soil.
(b)Update on Road Salt Impacts - Research Carried Out Elsewhere
Since the Toronto reports referred to above were written, several studies have been initiated or completed on assessing the
environmental impacts of road salt and alternative de-icing methods.
The most substantial initiative that has been recently introduced is the Canadian Federal Government's inclusion of road
salts on the Second Priority Substances List (PSL2) of December 16, 1995. The assessment of the first list of substances
was completed in 1994. The substances identified on the (PSL2) will be given priority for assessment to determine if they
are "toxic" under Section 11 of the Canadian Environmental Protection Act (CEPA).
The scope of the assessment for road salts will be limited to chloride salts: sodium chloride (NaCl), calcium chloride
(CaCl2), magnesium chloride (MgCl2), potassium chloride (Kcl), and brines used in road de-icing/anti-icing and dust
suppression, and the salt portion of abrasive mixtures. The anti-caking agents sodium ferrocyanide (also known as Yellow
Prussiate of Soda) and ferric ferrocyanide (also known as Prussian Blue) are also proposed for assessment as common
additives to sodium chloride for de-icing. In addition, hazards associated with possible alternatives to road salts will be
identified, in order to provide a more comprehensive view in support of risk management decisions.
Under the CEPA, a substance is defined as "toxic" if it enters or may enter the environment in amounts or under conditions
that may pose a risk to human health, the environment, or to the environment that supports human life. For substances
determined to be "toxic", management strategies, which integrate socio-economic considerations, are developed in
consultation with stakeholders and may include voluntary controls, process changes, substitutions, economic measures,
regulations, guidelines, codes of practice, or a combination of these measures.
An Environmental Resource Group (ERG), has been established to complete the assessment of road salts under the CEPA.
The group is made up of experts in the fields of groundwater, lakes and streams, plant toxicology, geochemistry, biology,
microbial processes, geology, roadway maintenance, risk assessment, risk management, and ecotoxicology. Working
groups are focussing on the effects of road salts in groundwater, the aquatic ecosystem, vegetation, wildlife and the effects
of sodium ferrocyanide. Work is underway to determine where road salts are used, the quantities in which they are applied,
and the locations and amounts of road salts in used snow, highway runoff and patrol yards. Two chapters (ground and
surface water and benthic sediments) are ready to be sent for scientific peer review. The majority of the supporting
document should be completed by May, 1999 and will then proceed to scientific peer review. A draft Assessment Report
will be prepared and made available for a 60-day public comment period. Following consideration of comments received,
the Assessment Report will be revised as appropriate and published with final conclusions as to whether or not the
substance is considered to be "toxic" as defined in CEPA. The legislated deadline for completion of the assessment of all
second priority substances is December 2000.
In Europe, a similar initiative to increase the understanding of the impact of de-icing salts and other chemicals on the
natural environment began in 1997. The Pollution of Groundwater and Soils by Road and Traffic Pollutants (POLMIT)
project, which is funded by the European Commission (EC), brings together the expertise of seven European based
research organizations (i.e., Transport Research Laboratory in the UK, Directorate General for Public Works and Water
Management in The Netherlands, Swedish Road and Transport Research Institute, Technical Research Centre of Finland,
Danish Road Institute, Laboratoire Central des Ponts et Chaussées in France, and Laboratório Nacional de Engerharia Civil
in Portugal). The principal outcome of the POLMIT project, which is slated for completion in 1999, will be comprehensive
knowledge, collated and disseminated in the form of a final report encompassing a best practice guide for minimising
potential pollution of groundwater and soil when designing, constructing and maintaining roads (which should include
winter maintenance).
(c)Reduction of Road Salt Impacts
Efforts have been made at reducing the corrosive and negative environmental impacts of road salting. Epoxy-coated
reinforcing bars and air-entrained concrete and/or high density concrete are used in the construction of new deck surfaces
to help limit the corrosion of steel reinforcing and deterioration of concrete. Research into the use of polymer and carbon
based reinforcing materials is also underway. During the last several years, automobile companies have intensified efforts
to protect cars from corrosion by special dipping processes, use of aluminized waxes, zinc-rich primers, galvanized steel
and greater use of other non-corrosive metals and plastics. In addition, some give the assembled cars an anti-corrosion
treatment.
2.Reduction of the Use of Road Salt:
The issue of reducing road salt application has been researched extensively in Canada, the United States and abroad.
Policies and practices that have been researched and implemented either on a full or pilot scale to reduce road salt use are
substitution with chemical alternatives or abrasives such as sand, placing less emphasis on salting over snow ploughing and
removal, and refinement and modernization of winter maintenance practices and equipment. All of the constituent former
municipalities of the City have for several years developed reduced salt application methods, using more advanced salt
application systems as this technology has become available. At least 7 other municipalities in Canada (i.e.,
Hamilton-Wentworth, Ottawa-Carlton, Calgary, Montreal, Quebec City, Sherbrooke, and Vancouver) have also adopted
the principle of reduction of road salt use.
(a)Chemical Alternatives to Road Salt
The most popular chemical alternatives to road salt are CMA (calcium magnesium acetate), sodium formate, calcium
chloride, magnesium chloride + PCI (a corrosion inhibitor called sulfonated polybenylpropane), and urea. The known or
potential effects that these chemical alternatives to road salt have on the environment vary widely and in some cases are not
known. The performance of these chemical alternatives vary greatly and may be less effective than salting.
Most of the chemical alternatives are less corrosive than road salt, but still exhibit properties that negatively impact the
natural environment or the impact on the natural environment is not fully understood. Urea, for example, has been found to
negatively impact aquatic life. Some studies suggest that CMA may impair soil quality and in some cases, water quality.
Sodium formate, although considered less corrosive to steel, has similar impacts on the natural environment as road salt.
The impacts of magnesium chloride + PCI on the environment and are not fully understood. One alternative, calcium
chloride, is less harmful to vegetation but is corrosive.
In recent years, CMA has received the most research attention as an alternative to road salt. One of the more
comprehensive studies that compared the costs of rock salt to CMA as a highway de-icer was completed by the United
States, Transportation Research Board (TRB) in 1991. The report suggested that the environmental benefits were superior
to road salt, however, the effectiveness and cost of CMA were inferior. CMA costs approximately 33 times as much as
sodium chloride and requires an application rate of 1.6 times that of salt.
In the 1990 joint report prepared by the City of Toronto's Medical Officer of Health and Commissioner of Public Works, it
was concluded that chemical alternatives to salt do exist and have proven to be effective as de-icing agents. It was also
concluded that these alternatives are still not economically feasible and questions regarding the environmental effects of
these chemical alternatives have not been fully resolved. Development of an alternative de-icer which is biodegradable and
eliminates environmental harm is still the focus of much research.
(b)Abrasive Alternatives
Abrasives are often cited as practical alternatives, but they have limitations. Disadvantages of abrasives are that they cannot
melt snow and ice, offer only temporary traction, are covered up by new snow, large quantities and frequent applications
are necessary and they must be cleaned up at great expense. Sand can obstruct and clog drainage ditches and storm drain
systems. Also, it is usually necessary to use some salt with abrasives in order to keep the abrasive stockpile from freezing.
(c)Mechanical Alternatives
Mechanical alternatives, such as snow ploughing or removal, at low snow accumulations are generally more expensive and
labour-intensive than salting. As snow accumulations increase, salting becomes less effective and more expensive than
ploughing or removal. A policy to plough at lower snow accumulations can result in reduced salt consumption. There are
negative environmental impacts associated with increased snow ploughing or removal instead of salting, such as increased
vehicle exhaust emissions and a potential for ice build-up on roadways.
(d)Winter Maintenance Practices
Considerable research is being done and programs are being implemented by other jurisdictions, such as the Regional
Municipality of Hamilton-Wentworth, the Ministry of Transportation of Ontario (MTO), the Transportation Association of
Canada, the United States Federal Highway Administration (FHWA), and the Salt Institute at improving and modernizing
winter maintenance practices and equipment, with emphasis on reducing salt use.
The Regional Municipality of Hamilton-Wentworth has installed computerized salt spreader controls on winter
maintenance vehicles, allowing greater control of salt applications on Regional roads minimizing the use of road salt.
The Ministry of Transportation of Ontario has initiated the Maintenance 2001 Project. The Project is designed to help build
an information-based maintenance management system for carrying out winter operations. It will review and demonstrate,
at one location (a 30 km test route along Hwy 26, between Barrie and Stayner), promising new winter maintenance
technology and practices under Ontario conditions, and then assist with technology transfer activities. The project
objectives are to introduce new technology, techniques and practices that will "reduce salt usage and negative impacts on
the environment, maintain a more consistent winter maintenance level of service, measure the performance of winter
maintenance contractors to ensure safety and standards are met, disseminate information on winter road conditions, and
foster opportunities for partnerships (MTO, municipalities, private contractors) to share information." The three categories
of technology/practices under investigation are "Advanced Road Weather Information Systems (ARWIS), advanced winter
maintenance procedures and equipment, and tools for monitoring maintenance activities and performance."
The Transportation Association of Canada is completing a study on the management of road salt that will produce three
documents scheduled for release in the spring of 1999. The first document is a Primer on Winter Maintenance for the
general public that provides information on the importance of salt use to maintaining a safe and efficient transportation
system that sustains Canada's economy. The second document is a series of eight concise, practical and focused Codes of
Practice for Salt Management. The third document is a longer and more comprehensive Salt Management Guide that
provides information on the subject of winter maintenance and salt usage.
In June 1996, the U.S. FHWA published a report titled "Manual of Practice for An Effective Anti-Icing Program: A Guide
For Highway Winter Maintenance Personnel". This manual provides information for successful implementation of an
effective highway anti-icing program. It is written to guide the maintenance manager in developing a systematic and
efficient practice for maintaining roads in the best conditions possible during a winter storm. It describes the significant
factors that should be understood and must be addressed in an anti-icing program, with the recognition that the
development of the program must be based on the specific needs of the site or region within its reach. The manual includes
recommendations for anti-icing practices and guidance for conducting anti-icing operations during specific precipitation
and weather events.
The Salt Institute has a training program for public works personnel responsible for snowfighting operations that focuses
on "Sensible Salting". "Sensible Salting" emphasizes getting the most out of every application of de-icing salt, maintaining
the safest roads possible in the most economical way while protecting the environment. According to the Salt Institute, a
good "Sensible Salting" program should include personnel training, good equipment, calibration of spreaders, use of
automatic controls, adequate covered storage, proper maintenance around storage areas, and an awareness of safeguarding
the environment by all who use salt.
The principle of reducing salt usage through implementation of winter maintenance policies and practices should be
addressed in a comprehensive winter services report prepared by the Transportation Services Division. In the meantime,
Works and Emergency Services staff will continue to monitor the relative successes and acceptance of initiatives at
reducing road salt use within other jurisdictions.
Public Awareness:
Although the potential environmental benefits of chemical alternatives to road salt are either limited or not well known,
informing the public fosters a greater awareness of the alternatives and their advantages, where applicable. This could be
achieved by the publication of an appropriate brochure. In particular, the public should be informed about the potential
benefits or misconceptions that exist with chemical alternatives to road salt. The brochure should also discuss mechanical
alternatives. The information contained in the brochure should also be displayed on the City's Internet site.
Conclusions:
The issue of the environmental impacts of road salt is a significant one. The Canadian Government has recognized the need
to conduct an assessment on the environmental and health impacts of road salts. New initiatives at reducing road salt use
are continually being introduced, researched and in some cases implemented. The City of Toronto should continue to take
an active role in implementing appropriate strategies for reducing salt use and should publish information on its practises
regarding the use of salt in a brochure and on the City's Internet site.
Contact Name:
Jerry Higgins, P.Eng., M.Eng.
Environmental Services Section, Technical Services Division
Tel: 392-7705; Fax: 392-1456, E-Mail: jhiggins@toronto.ca
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The Urban Environment and Development Committee also had before it Clause 44 of the City Services Committee Report
No. 2, 1991 which was received by the Council of the Corporation of the City of Toronto at its meeting No. 3 on February
4, 1991, which was forwarded to all Members of Council with the agenda of the Urban Environment and Development
Committee for its meeting of May 17, 1999, and a copy thereof is on file in the office of the City Clerk.
(City Council on June 9, 10 and 11, 1999, had before it, during consideration of the foregoing Clause, the following report
(May 19, 1999) from the City Clerk:
Recommendation:
The Works and Utilities Committee recommends that the report dated April 28, 1999, from the Commissioner of Works
and Emergency Services, embodied in Clause No. 17 of Report No. 8 of The Urban Environment and Development
Committee, be struck out and referred to the Works Committee for further consideration.
The Works and Utilities Committee reports, for the information of Council, having requested the Commissioner of Works
and Emergency Services to:
(i)include the Toronto Transit Commission, major highrise landowners, schools, malls and any other relevant
institutions in the notification process; and
(ii)submit a report to the Works Committee as soon as possible providing further information on mechanical alternatives
to the use of road salt, including a cost/benefit analysis.
Background:
The Works and Utilities Committee on May 19, 1999, had before it a report (April 28, 1999) from the Commissioner of
Works and Emergency Services responding to the request from City Council to consider the road salt motion that was
before City Council on November 25, 26 and 27, 1998; and recommending that:
(1)the Commissioner of Works and Emergency Services report to the Committee following the publication of the results
of the Canadian Federal Government's research program on the toxicity of road salt; and
(2)Works and Emergency Services staff prepare an information bulletin outlining possible alternatives to road salt,
including the costs and benefits, and make this information available to other major users of salt and public-at-large upon
request, and that the same information be made available:
(a)on the City's Internet website; and
(b)as part of the annual winter maintenance brochure prepared by Transportation Services.
The Committee also had before it the following communications:
(i)(undated) from Mr. John Hopkins, Storm Water Group, advising that the matter of salt on roads requires more
background; and providing comments and recommendations with respect thereto.
(ii)(undated) from Ms. Karey Shinn, Member, Storm Water Group, requesting, on behalf of the Storm Water Group, that
consideration of the report respecting the Road Salt Environmental Impact Study and reduction of road salt use be
deferred to the next meeting of the Works Committee; and advising that it is generally felt that the information required to
put together a brochure on this subject is incomplete.
(iii)(May 18, 1999) from Leslie Woo, Member, Toronto Bay Initiative Co-ordinating Circle, forwarding correspondence
outlining the Toronto Bay Initiative's pilot project to treat stormwater run-off from the Gardiner Expressway, prior to
entering Toronto Bay, in support of the request for deferral of the report respecting the Road Salt Environmental Impact
Study and Reduction of road salt use.
(iv)(March 9, 1999) from Mr. Dalton Shipway, Storm Water Group, forwarding a submission with respect to the practice
of snow dumping and environmental impacts on land, water quality and aquatic life.
The following persons appeared before the Works and Utilities Committee in connection with the foregoing matter:
-Ms. Karey Shinn, Member, Storm Water Group;
-Mr. John Hopkins, J.L.H. Services Ltd., and a Member of the Storm Water Group, and submitted material with respect
thereto; and
-Councillor Norm Kelly, Scarborough Wexford.)
