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==Salt Alternatives==Due to rock salt's numerous impacts on both infrastructure and the environment numerous studies have been conducted to determine if there are adequate alternatives to the practice of salt application to parking lots and roads. These include sand, organic de-icing materials (agricultural by-products), and salt water brine to name a few.Below find a summary table of common de-icers and alternatives in comparison to rock salt regarding lowest working temperature, cost estimations and average application rates. {|class="wikitable"|+Comparison of Commonly used De-icers|-!Deicer!Cost Estimate (low $ - high $$$$)!Typical Application Rates (average range)!Lowest Practical Working Temperature (°C)|-|NaCl (Rock Salt)|style="text-align: center;" |$|~130 kg/2 lane km, depending on conditions (range 70-220 kg/2-lane km in Lake Simcoe watershed)|style="text-align: center;" |-9|-|MgCl2 (Liquid Brine)|style="text-align: center;" |$$|Liquid anti-icing: 35-59 L/2-lane km|style="text-align: center;" |-15|-|CaCl2 (Liquid Brine)|style="text-align: center;" |$$$|Liquid anti-icing: 35-59 L/2-lane km|style="text-align: center;" |-29|-|Treated Rock Salt|style="text-align: center;" |$$|72-130 kg/2-lane km|style="text-align: center;" |-17|-|Calcium Magnesium Acetate|style="text-align: center;" |$$$$|219-292 kg/2-lane km (for first application, lower for subsequent due to residual effect)|style="text-align: center;" |-7|-|Agricultural By-Products|style="text-align: center;" |Varied Cost ($$ - $$$$)|Varies; often used to pre-wet rock salt – less salt is required, lowest effective temperature is reduced|style="text-align: center;" |-17 to -23|}===Agricultural By-Products & Brine===Many municipalities have found treated rock salt to be worth the extra investment, due to its increased effectiveness at lower temperatures and lower application rate when compared to standard rock salt application practices. The process of pre-wetting rock salt with brine or an agricultural by-product (beet juice for example) as it is applied can help the mixture better adhere to road and pavement surfaces better and reduce excess waste and can enhance the effectiveness of rock salt application below -12°C. To note, the effectiveness of agricultural by-products is still under some evaluation, as some major cities, including Toronto, use it under certain conditions, several Lake Simcoe watershed municipalities have tested it and found it not to be as effective as rock salt. Furthermore, agricultural by-products have to be applied before a snowfall event to melt the fallen snow in a relatively short period of time, which generally is not possible or practical (if applied after a snowfall event it takes a long time to begin the melting process). Read more about these alternative applications in [https://sustainabletechnologies.ca/app/uploads/2020/03/Alternatives-to-salt-technical-brief.pdf STEP's Technical Brief: Alternatives to Salt]<ref>STEP. 2020. Alternatives to Salt: What else melts snow and ice? Technical Brief. https://sustainabletechnologies.ca/app/uploads/2020/03/Alternatives-to-salt-technical-brief.pdf</ref>. [[File:Sand accumulated road.PNG|thumb|250px|Sand accumulates on the ride of the road after being applied after a snowfall event. Sand can travel into nearby watercourses, wetlands, and increases clean-up associated costs for the municipality. Photo source: [https://sustainabletechnologies.ca/app/uploads/2020/03/Sand-vs-Salt-tech-brief.pdf LSRCA, 2018.]<ref>LSRCA. 2018. Sand versus Salt: Should sand be used for winter maintenance? Technical Bulletin, Volume 1 October 2018. https://sustainabletechnologies.ca/app/uploads/2020/03/Sand-vs-Salt-tech-brief.pdf</ref>]]Detailed analysis of the performance of varying de-icer agents and liquid brine can be found in STEP's earlier technical brief entitled, [https://sustainabletechnologies.ca/app/uploads/2015/11/AlternativeSalt_TechBrief_Nov2015.pdf Evaluation of Organic Anti-icing Materials for Winter Maintenance].<ref>STEP. 2015. Evaluation of Organic Anti-icing Materials for Winter Maintenance. Technical Brief. Salt Management. https://sustainabletechnologies.ca/app/uploads/2015/11/AlternativeSalt_TechBrief_Nov2015.pdf</ref>. The document describes the practice of "anti-icing", (applying liquid brine solutions to paved surfaces before a winter storm) to help prevent ice and snow from bonding to the roadway surface, which in turn helps to reduce the amount of rock salt required to remove salt and ice.===Sand===Property managers often turn to sand as an alternative to salt, as it is thought to be a less harmful option. Sand has been used, either on its own or mixed with salt, as a core part of many municipalities’ or individual property managers’ winter maintenance practices. It is used similarly to rock salt as it is applied to increase friction between snowy or icy pavement and the vehicles/pedestrians passing over it. Of those municipalities that use sand, rural ones with a higher proportion of gravel roads use almost exclusively sand (with a small percentage of salt mixed in to prevent freezing and caking), while other municipalities often use a sand-salt mix at various ratiosThe general issues with sand are that:*Most sand applied blows off the road within relatively few (e.g. 8-12) vehicle passes at speeds over 40 km/hr (general speed limits of most municipal subdivision streets); rendering any improvement in friction temporary, at best. *Pre-wetting can help sand adhere to the road, but there is little to no increase in its friction coefficient even with this pretreatment approach. *When sand mixes with melting snow it doesn't embed itself in the snow but rather becomes more of a slushy mixture that accumulates on the side of roads, or worse within SWM features (catch basins, stormwater ponds, etc.). **The associated cost municipalities incur as a result of sand accumulation along roadways, curbsides and in SWM features are due to the additional effort required (more frequent catchbasin cleanouts, etc.) and the cost of sweeping up this material at the end of each winter season to reduce ongoing environmental impacts.*Due to contamination of sand, disposal is becoming a more complicated, and therefore costly process causing a number of municipalities to re-evaluate their winter maintenance programs, when it comes to using sand.Read [https://sustainabletechnologies.ca/app/uploads/2020/03/Sand-vs-Salt-tech-brief.pdf LSRCA's Technical Bulletin: Sand versus Salt]<ref>LSRCA. 2018. Sand versus Salt: Should sand be used for winter maintenance? Technical Bulletin, Volume 1 October 2018. https://sustainabletechnologies.ca/app/uploads/2020/03/Sand-vs-Salt-tech-brief.pdf</ref> document to learn more about exploring the efficacy of the use of sand for winter maintenance, its associated environmental issues, and where its use is most appropriate.
→Salt Alternatives
For more information on the practices and research supporting the suggested benefits, see [https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf STEP, 2022]<ref name="example6" /> and [https://sustainabletechnologies.ca/app/uploads/2022/02/roadsalt-tac-full-doc.pdf TAC, 2013], and associated reference materials.
For more information on the practices and research supporting the suggested benefits, see [https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf STEP, 2022]<ref name="example6" /> and [https://sustainabletechnologies.ca/app/uploads/2022/02/roadsalt-tac-full-doc.pdf TAC, 2013], and associated reference materials.
==Site Design Strategies for Salt Reduction==
==Site Design Strategies for Salt Reduction==