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===Observed Stream Concentrations=== Line 82:
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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.
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*The use of [[Permeable pavements|permeable pavers]]: these improve drainage and prevent melt water from ponding and refreezing.Line 326:
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[[File:Salt comparison.PNG|thumb|520px|link=https://sustainabletechnologies.ca/app/uploads/2019/06/Procurement-Guidance-Parking-Lot-Snow-and-Ice-Mgmt.pdf|Summary of Salt Reduction Measures and their estimated impact on salt use and contract costs from [https://sustainabletechnologies.ca/app/uploads/2019/06/Procurement-Guidance-Parking-Lot-Snow-and-Ice-Mgmt.pdf STEP's Procurement Guidance for Parking Lot Snow and Ice Management]<ref>STEP. 2019. Procurement Guidance for Parking Lot Snow and Ice Management. Version 2.0 https://sustainabletechnologies.ca/app/uploads/2019/06/Procurement-Guidance-Parking-Lot-Snow-and-Ice-Mgmt.pdf</ref>]] Contracts for snow and ice management on private parking lots are typically oriented towards ensuring that plowing and salting promotes safe conditions throughout the winter, and that interruptions to regular business operations are kept to a minimum. The first thought of many people may be that applying more salt is safer for their patrons and workers but, applying more than is necessary not only harms the environment, as previously mentioned but also shortens the life of parking lot surfaces and can accelerate the process of corrosion of nearby buildings or transportation infrastructure on site, not to mention the extra cost of unnecessary road salt application. Property owners, businesses and contractors have control over how much salt is applied through their snow and ice management contracts, and the diligence with which they manage and oversee these contracts. The [https://sustainabletechnologies.ca/app/uploads/2019/06/Procurement-Guidance-Parking-Lot-Snow-and-Ice-Mgmt.pdf Procurement Guidance for Parking Lot Snow and Ice Management] by STEP <ref>STEP. 2019. Procurement Guidance for Parking Lot Snow and Ice Management. Version 2.0 https://sustainabletechnologies.ca/app/uploads/2019/06/Procurement-Guidance-Parking-Lot-Snow-and-Ice-Mgmt.pdf</ref> describes various clauses and conditions that can be considered by these groups to be included in contracts to promote the responsible use of road salts. A summary of the measures are provided in with estimates of the impact on salt use, and the potential influence these may have on contract costs. Businesses can help reduce over-salting by ensuring that rock salt during the winter months is applied responsibly on parking lots and walkways. An easy way to do this is by ensuring that your snow and ice maintenance contract includes provisions requesting that industry best practices be employed and that associated operators are adequately trained. Some BMP for procurement for rock salt application services include:# '''Effective Pricing of Services''': Contract pricing by a lump sum by season or a fixed sum per event (with extra costs associated with standby time) are common, but a combination of both payment options in the contract may create a financial incentive for both the parking-lot owner and salt operator to require less salt.# '''Accurate Salt Delivery''': Updated and well-maintained salt application devices (i.e. salt spreaders) that can be calibrated to function and apply salt automatically based on the speed of the vehicle can greatly reduce the amount of rock salt applied and can better digitally track the amount used as well.# '''Reducing Liability Risk''': Ensuring records and evidence of when, where and how plowing and salting practices were performed on site better protect the owner of the parking lot and contractor who applied the practices from potential slip and fall lawsuits. # '''Efficient Application''': Consideration of pre-wetting or anti-icing with liquid salt brine before events will help accelerate the melting process during and after an event and help salt better adhere to the road/parking lot surface.# '''Consideration of Chloride Alternatives''': Alternatives previously mentioned on this page such as acetates, formates, agricultural by-products (beet juice) can be used instead of rock salt (where feasible) or can be used as an anti-icing / pre-wetting agent.# '''Well Informed Decision Making Processes''': Use of local weather forecasts, up-to-the-minute road information systems, internet based radar tracking and infrared thermometers to determine pavement temperatures can better decision making options that save time on salt, contractor crew capacity and money.# '''Trained Professionals''': Requesting evidence of experience and requiring training and certification through the [http://www.smartaboutsalt.com/training Ontario Smart about Salt Program] will help to ensure that the contractor selected and property management staff have the skills necessary to implement best practices for road salt application. To learn more about STEP's [https://sustainabletechnologies.ca/app/uploads/2019/06/Salt-application-best-practices-for-winter-maintenance-contracts-brochure.pdf Salt Application Best Practices document for Winter Maintenance Contracts]<ref>STEP. 2019. Salt Application Best Practices for Winter Maintenance Contracts. Technical Brief. https://sustainabletechnologies.ca/app/uploads/2019/06/Salt-application-best-practices-for-winter-maintenance-contracts-brochure.pdf</ref> click on the hyperlink. ==Parking Lot Friction Testing==[https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf LSRCA's Technical Bulletin: Alternatives to Salt]<ref>LSRCA. 2020. Friction and Parking Lots. Technical Bulletin, Volume 3 September 2020. https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf</ref> is a valuable technical brief which covers BMPs that have been developed specifically for winter maintenance in parking lots. Along with recommendations around the proper use and calibration of equipment, many of these practices relate to plowing the lot and walkways before applying salt, and applying the recommended amount of salt for the conditions. Several studies have been conducted, by industry and academia, to determine what the “right” amount of salt is, and, while “proper” application can vary depending on temperature and conditions 58 g/m2 (or 13 lb/1000 ft2) has been suggested as a reasonable rate to use for “moderate” winter events (Hossain, K. and Fu, L., 2015), while in recent studies of commercial parking lots by LSRCA, the typical real-world application rates tended to be closer to 90 g/m2 (or 18 lb/1000 ft2), and can often be much higher. This report talks about main considerations contractors face in maintaining parking lots in winter:*What application rate should be used? *What is the level of service expected by the client, for which the bare pavement return time is a common measure? **(This is the amount of time it takes after treatment to achieve a bare surface) In order to better understand these questions; in 2017 the LSRCA obtained a friction tester, with a goal of quantifying the effectiveness of various practices and salt application rates. LSRCA’s friction testing showed that bare pavement is safest, as it has the highest friction value, and that the over-application of salt does not translate to safer conditions. To read more about the friction tester results continue on below, through the rest of this section. [[File:Measuring friction LSRCA office.png|thumb|500px|This image demonstrates the two extremes of LSRCA’s friction testing: a perfectly clear and dry surface, with a µ value of 0.9 and the same surface covered in a light layer of snow, with a µ of only 0.11.]]As can be seen in the inset table, the unit for measuring friction is ‘µ’, and the closer to 1.00 the µ value, the safer the surface. A high µ, however, is not the only measure of safety – many smooth indoor floors will have low µ values, in the range of 0.3 to 0.4, and they are generally not considered unsafe. Through this study, friction of several different surfaces, which received varying treatments was measured by LSRCA staff. <br></br>{|class="wikitable"|+Friction Values and Related Road Surface Conditions|-!Measured Friction Value (µ)!Road Surface Condition|-|0.8 - 1.00|Dry, New Asphalt|-|0.50 - 0.80|Wet Asphalt|-|0.30 - 0.50|Wet Sand on Ice|-|0.25 - 0.30|Dry Sand on Ice|-|0.25 - 0.25|Dry Ice|-|0.05 - 0.15|Wet Ice|}
High volumes of salt are often applied because contractors, property managers, and parking lot users feel that the more salt there is, the safer the surface is to walk or drive on. However, a surface that has been treated at an appropriate rate, (which is slightly wet with a small amount of salt residue) has a much higher friction value (μ); with the level of service achieved far more efficiently, than when compared to the same surface where rock salt has been heavily applied (over salted).
Through this work, as referenced above - LSRCA staff documented higher friction values on untreated surfaces than on surfaces with large volumes of product; the µ value of a surface may remain low if it has only been shoveled or plowed. While shoveling is an important part of the winter maintenance process, practitioners need to consider the site and predicted conditions on a day-to-day basis to determine how to attain the safest surface for vehicle and foot traffic. In many cases the sun or traffic may melt the residual snow on a shoveled or plowed surface without any further treatment being necessary (saving both time and money); while in other cases, some salt, applied at an appropriate rate, may be necessary. ====Higher Costs, Little Benefit====Friction testing has demonstrated that bare pavement is safest, as it has the highest friction value, and that the over-application of salt does not always translate to safer conditions. Simply put, applying salt at the prescribed rate for the conditions and shoveling or plowing where appropriate will attain a higher friction rate than an overapplication of salt. ''What is a reasonable amount of time to achieve the desired level of service?'': **For example, many commercial properties keep hours between 9:00 am and 9:00 pm, which would mean that the lot does not need to be clear until shortly before 9:00 am. The table below demonstrates the time it would take to reach bare pavement at typical industry-recommended application rates, in a situation where the temperature is between -7 and -9 °C, with between 0.5 and 1.5 cm of snow on the ground. The rate may need to be increased or decreased slightly to achieve the desired level of service depending on varying factors related to traffic, sunlight, type of snow, and/or pavement type. </br>{|class="wikitable"|+Time to Reach Bare Pavement Scenario Comparison<br></br>|-!'''Difference Among Scenarios'''!'''Time to bare pavement (hrs)'''!'''Application Rate (g/m2)'''!'''<u><span title="Note: Assuming lot size of 15 ha (the approximate size of an LSRCA study lot).">Volume of salt used for each application (kg)*</span></u>'''!'''<u><span title="Note: Assuming 70 applications.">Total salt applied/season (tonnes)**</span></u>'''!'''Material costs/season (assuming $100/tonne)'''|-|'''Scenario 1'''<br></br>|2|87|13,050|913|$91,300|-|'''Scenario 2'''<br></br>|3|58|8,700|609|$60,900|-|'''Difference'''<br></br>|1|29|4,350|304|$30,400|-|}
As the "''Time to Reach Bare Pavement Scenario Comparison''" above demonstrates, significant salt and cost savings could be seen in a typical big box store, commercial business or institutional building's parking lot by simply reducing the application rate of rock salt and extending the time to bare pavement by one hour. To note, this is only the material cost of the salt (which varies, but has been [https://www.cbc.ca/news/canada/ottawa/ottawa-contractors-road-salt-price-hike-1.4934369 higher than $100/tonne in recent years] (Tumilty, 2018)<ref>Tumilty, R. 2018. Rise in road salt prices hits local contractors. Available at: https://www.cbc.ca/news/canada/ottawa/ottawa-contractors-road-salt-price-hike-1.4934369 (Accessed: 24 Mar., 2022)</ref>. Over-application of salt has been noted to cause significant damage to parking lot infrastructure, including issues with concrete, corrosion of railings, damage to landscaping materials, and damage to interior buildings' flooring. Reducing the application rate would decrease the rate at which this damage occurs, as a result helping to minimize the amount needed to repair or replace at a given property each year. All of this without sacrificing the safety of parking lot users.
==External links==
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→Case Studies & External Links
*Sodium also has an aesthetic objective of 200 mg/L based on taste, as well as a guideline of 20 mg/L for people on sodium restricted diets
*Sodium also has an aesthetic objective of 200 mg/L based on taste, as well as a guideline of 20 mg/L for people on sodium restricted diets
==Observed Chloride Levels in Streams Concentrations==
Monitoring data show that our freshwater resources are become increasingly salinized, particularly in urban areas. As the graphic shows, several urban streams in the GTA have average chloride concentrations exceeding the chronic toxicity threshold, and at some monitoring stations, even the acute toxicity threshold is exceeded. This is not just a winter problem; it can take months for water to move through the soils and into the rivers, resulting in high concentrations even in the spring and summer during sensitive life stages for many aquatic species.
Monitoring data show that our freshwater resources are become increasingly salinized, particularly in urban areas. As the graphic shows, several urban streams in the GTA have average chloride concentrations exceeding the chronic toxicity threshold, and at some monitoring stations, even the acute toxicity threshold is exceeded. This is not just a winter problem; it can take months for water to move through the soils and into the rivers, resulting in high concentrations even in the spring and summer during sensitive life stages for many aquatic species.
==Salt Reduction Best Practices==
==Salt Reduction Best Practices==
Since salt is not removed by traditional best practices, reducing application rates to only what is needed to achieve pavement safety requirements is the best means of managing impacts of salt on the environment and infrastructure. Pavement friction testing has shown that salting beyond the required amount does not translate into improved safety: [https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf LSRCA's Technical Bulletin: Alternatives to Salt].<ref>LSRCA. 2020. Friction and Parking Lots. Technical Bulletin, Volume 3 September 2020. https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf</ref>
Since salt is not removed by traditional best practices, reducing application rates to only what is needed to achieve pavement safety requirements is the best means of managing impacts of salt on the environment and infrastructure. Pavement friction testing has shown that salting beyond the required amount does not translate into improved safety: [https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf LSRCA's Technical Bulletin: Alternatives to Salt].<ref name="example9">LSRCA. 2020. Friction and Parking Lots. Technical Bulletin, Volume 3 September 2020. https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf</ref>
A review of salt management best practices for parking lots, private drives and walkways is provided by [https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf STEP (2022)]<ref name="example6">Van Seters, T. 2022. Review of Snow and Ice Control Practices on Parking Lots and Walkways. Toronto and Region Conservation Authority, Sustainable Technologies Evaluation Program. Ontario. https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf</ref>. The Transportation Association of Canada's (TAC), [https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/roadsalt-1.pdf Synthesis of Salt Management Best Practices]<ref>Transportation Association of Canada (TAC). 2013. Syntheses of Best Practices Road Salt Management. April 2013. https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/roadsalt-1.pdf</ref> and [https://clearroads.org/research-by-topic/ Clear Roads research]<ref>Clear Roads. 2022. Research by Topic. Accessed - May 16 2022: https://clearroads.org/research-by-topic/</ref>and provides best practice resources more relevant to municipalities and road authorities. The following sections outline what property owners/managers and winter maintenance professionals can do to avoid excess salting.
A review of salt management best practices for parking lots, private drives and walkways is provided by [https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf STEP (2022)]<ref name="example6">Van Seters, T. 2022. Review of Snow and Ice Control Practices on Parking Lots and Walkways. Toronto and Region Conservation Authority, Sustainable Technologies Evaluation Program. Ontario. https://sustainabletechnologies.ca/app/uploads/2022/04/Snow-and-Ice-Control-BMPs-for-Parking-lots-and-Sidewalks.pdf</ref>. The Transportation Association of Canada's (TAC), [https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/roadsalt-1.pdf Synthesis of Salt Management Best Practices]<ref>Transportation Association of Canada (TAC). 2013. Syntheses of Best Practices Road Salt Management. April 2013. https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/roadsalt-1.pdf</ref> and [https://clearroads.org/research-by-topic/ Clear Roads research]<ref>Clear Roads. 2022. Research by Topic. Accessed - May 16 2022: https://clearroads.org/research-by-topic/</ref>and provides best practice resources more relevant to municipalities and road authorities. The following sections outline what property owners/managers and winter maintenance professionals can do to avoid excess salting.
* [https://www.peelregion.ca/transportation/winter/maintenance-commercial.asp#propertyowners Peel Region]
* [https://www.peelregion.ca/transportation/winter/maintenance-commercial.asp#propertyowners Peel Region]
* [https://www.regionofwaterloo.ca/en/living-here/winter-maintenance-for-commercial-properties.aspx Waterloo Region]
* [https://www.regionofwaterloo.ca/en/living-here/winter-maintenance-for-commercial-properties.aspx Waterloo Region]
* [https://www.hamilton.ca/sites/default/files/media/browser/2022-01-17/coh-salt-management-plan2021.pdf Hamilton Region]
* [https://www.hamilton.ca/sites/default/files/media/browser/2022-01-17/coh-salt-management-plan2021.pdf Hamilton Region]<br>
<br>
===Winter Maintenance Professionals===
===Winter Maintenance Professionals===
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==
Generally, the [[vegetation]] growing closest to the source will be most strongly affected by salt. Plants actively growing in late winter (when salt levels are highest) are also more significantly affected. Therefore, warm season [[Graminoids: List|grasses]] offer an advantage over cool season grasses, because they emerge later in the spring when excess salt has been flushed away.
Generally, the [[vegetation]] growing closest to the source will be most strongly affected by salt. Plants actively growing in late winter (when salt levels are highest) are also more significantly affected. Therefore, warm season [[Graminoids: List|grasses]] offer an advantage over cool season grasses, because they emerge later in the spring when excess salt has been flushed away.
{{:turf}}.
{{:turf}}
For other species of trees and shrubs, see the [[Plant lists]] page for salt tolerant plants suitable for LID.
[[File:Brine-Storage-Tank-1-scaled.jpg|thumb|430px|Example of three brine holding tanks that can reuse meltwater from salt induced snowmelt to be reused on a pavement surface i na high traffic area. These systems are generally built with corrosion-free materials to maximize the product's lifetime. Photo Source: [https://www.camionsystems.com/product/brine-storage-tank/ Camion]™<ref>Camion™. 2022. Brine Storage Tank. Accessed 28 Mar. 2022. https://www.camionsystems.com/product/brine-storage-tank/</ref>]]
[[File:Brine-Storage-Tank-1-scaled.jpg|thumb|430px|Example of three brine holding tanks that can reuse meltwater from salt induced snowmelt to be reused on a pavement surface i na high traffic area. These systems are generally built with corrosion-free materials to maximize the product's lifetime. Photo Source: [https://www.camionsystems.com/product/brine-storage-tank/ Camion]™<ref>Camion™. 2022. Brine Storage Tank. Accessed 28 Mar. 2022. https://www.camionsystems.com/product/brine-storage-tank/</ref>]]
===Other Design Features===
===Other Design Features===
Other options that can be considered to reduce the amount of salt that needs to be applied in a parking lot include:
Other options that can be considered to reduce the amount of salt that needs to be applied in a parking lot include:
*Seasonally closing parking areas: many parking lots have areas that are infrequently used outside of the holiday shopping period. These areas can be closed and not maintained through much of the winter season, reducing both the effort and amount of salt required.
*Seasonally closing parking areas: many parking lots have areas that are infrequently used outside of the holiday shopping period. These areas can be closed and not maintained through much of the winter season, reducing both the effort and amount of salt required.
*Shaded Canopies: With roof canopies over major pedestrian walkways and entrances from parking lots to building enclosures, little to no snow or ice will fall in these high-traffic areas, resulting in reduced salt application. Consideration should be taken for the runoff generated from the canopy stormwater or snowmelt when weather begins to warm to limit the potential for of ponding/refreezing on the walkway.
*Shaded Canopies: With roof canopies over major pedestrian walkways and entrances from parking lots to building enclosures, little to no snow or ice will fall in these high-traffic areas, resulting in reduced salt application. Consideration should be taken for the runoff generated from the canopy stormwater or snowmelt when weather begins to warm to limit the potential for of ponding/refreezing on the walkway.
*Brine holding tanks: Collection of first flush (high chloride concentration) melt water runoff from a salt induced snowmelt (as opposed to rain and temperature induced snowmelt) has the potential to be beneficial if captured and reused as an anti-icing or pre wetting solution. In order to collect the first flush runoff, an electronically actuated valve controlled by an electrical conductivity sensor would be installed at the desired conveyance point to divert and collect the high chloride concentration runoff into a brine holding tank. The brine holding tank would be placed below ground and a pump could be connected to pump the brine solution into an anti-icing tank or directly used to pre-wet rock salt. <ref>LSRCA. 2015.Parking Lot Design Guidelines to Promote Salt Reduction. GHD. 11115623 (2). https://www.lsrca.on.ca/Shared%20Documents/Parking-Lot-Design-Guidelines/Parking-Lot-Guidelines-Salt-Reduction.pdf</ref>
*Brine holding tanks: Collection of first flush (high chloride concentration) melt water runoff from a salt induced snowmelt (as opposed to rain and temperature induced snowmelt) has the potential to be beneficial if captured and reused as an anti-icing or pre wetting solution. In order to collect the first flush runoff, an electronically actuated valve controlled by an electrical conductivity sensor would be installed at the desired conveyance point to divert and collect the high chloride concentration runoff into a brine holding tank. The brine holding tank would be placed below ground and a pump could be connected to pump the brine solution into an anti-icing tank or directly used to pre-wet rock salt. <ref>LSRCA. 2015.Parking Lot Design Guidelines to Promote Salt Reduction. GHD. 11115623 (2). https://www.lsrca.on.ca/Shared%20Documents/Parking-Lot-Design-Guidelines/Parking-Lot-Guidelines-Salt-Reduction.pdf</ref>
==Procurement Guidance==
==Case Studies & External Links==
===Case Studies===
A series of STEP case studies highlighting the effectiveness of different salt management practices is currently being developed. A brief synopsis of some of these case studies is provided in Appendix B of Van Seters, 2022. Full case study documents will be posted here when available.
===Procurement Best Practices===
*[https://ottawariverkeeper.ca/2021-2022-road-salt/ The 2021-2022 Road Salt Program at Ottawa Riverkeeper]<ref>Oswald, 2021. Road salt reduction on Ryerson University campus. Information Sheet. Presentation by C. Oswald at the Ottawa Riverkeeper salt management forum in April 2021. Ottawa Riverkeeper. January 18, 2022. Accessed May 16 2022. https://ottawariverkeeper.ca/2021-2022-road-salt/</ref>
**This ongoing study is being conducted to evaluate the feasibility and environmental benefits (specifically, the reduction of chloride (Cl) entering the environment) of using direct liquid application (i.e., NaCl brine) on Ryerson campus for both anti-icing and de-icing. Updated reports and findings will be posted here once published
[[File:(2)Measuring friction LSRCA office.png|thumb|500px|Friction values for a properly treated surface (left) with a small amount of residue (µ =0.63) and an over salted surface right, which has a much lower friction value (µ =0.26).]]
[[File:Anti-icing truck.PNG|thumb|500px|De-icer agent applied to a roadway before a precipitation rent (Source: STEP, 2019)<ref name="example10" />]]
*[https://pub-peelregion.escribemeetings.com/filestream.ashx?DocumentId=9868 Using Liquids to Reduce Winter salt Use on Commercial Parking Lots]<ref>: Murison, L., Oswald, C., Gillion, E., and International Landscaping Inc. 2022. Salt Management - Partnership and Outreach Update. https://pub-peelregion.escribemeetings.com/filestream.ashx?DocumentId=9868.</ref>
**This ongoing study is being conducted by Peel Regio and LSRCA staff, along with contractor International Landscaping Inc. to evaluate the feasibility and environmental benefits (specifically, the reduction of chloride (Cl) entering the environment) of using liquid anti-icing with NaCl brine (with and without beet juice additive) on commercial parking lots. Updated reports and findings will be posted here once published
[[File:(3)Measuring friction LSRCA office.png|thumb|500px|The picture above shows the same walkway where more than 10 times the generally recommended amount of salt was applied in the photo on the left, and only shoveling was done in the photo on the right, and both µ values were in the low 0.20s.]]
*[https://www.regionofwaterloo.ca/en/living-here/resources/Documents/water/was-protect_closed_sign_program.PDF Closing Areas to Reduce Salt Use and Winter Maintenance Costs]<ref>Region of Waterloo. 2020. Salt reduction partnership. Region of Waterloo, Water Services. https://www.regionofwaterloo.ca/en/living-here/resources/Documents/water/was-protect_closed_sign_program.PDF</ref>
**Ongoing study by the Region of Waterloo to explore the feasibility and interest in reducing salt use and maintenance costs by establishing outreach campaigns and support programs that encourage property owners and managers (of ICI properties) to close under-used areas of their properties during the winter, which can be a very successful means to reduce salt use, and provide significant savings on winter maintenance costs.
*[https://sustainabletechnologies.ca/app/uploads/2019/06/Salt-application-best-practices-for-winter-maintenance-contracts-brochure.pdf Salt Application Best Practices document for Winter Maintenance Contracts]<ref>STEP. 2019. Salt Application Best Practices for Winter Maintenance Contracts. Technical Brief. https://sustainabletechnologies.ca/app/uploads/2019/06/Salt-application-best-practices-for-winter-maintenance-contracts-brochure.pdf</ref>
**Businesses can help reduce over-salting by ensuring that rock salt during the winter months is applied responsibly on parking lots and walkways. An easy way to do this is by ensuring that your snow and ice maintenance contract includes provisions requesting that industry best practices be employed and that associated operators are adequately trained. Some BMP for procurement for rock salt application services include:
*** Effective Pricing of Services
***Accurate Salt Delivery
***Reducing Liability Risk
***Efficient Application
***Consideration of Chloride Alternatives
*Depending on the operating hours of the property being maintained, it may be possible to reduce the salt application rate without sacrificing the desired level of service.
***Well Informed Decision Making Processes
***Using Trained Professionals through the [http://www.smartaboutsalt.com/training Ontario Smart about Salt Program]
*[https://sustainabletechnologies.ca/app/uploads/2021/05/Friction-and-Parking-Lots.pdf LSRCA's Technical Bulletin: Alternatives to Salt].<ref name="example9" />
**This technical bulletin by LSRCA discusses the issue of high levels of salt application, and how contractors, property owners and municipalities can save time and money by looking at the emerging research which shows how salt use can also be optimized in parking lots. This research was done by using a friction tester, with a goal of quantifying the effectiveness of various practices and salt application rates.
*[https://journals.sagepub.com/doi/10.1177/0361198120957320 Winter Maintenance of Permeable Interlocking Concrete Pavement: Evaluating Opportunities to Reduce Road Salt Pollution and Improve Winter Safety]<ref>Marvin, J.T., Scott, J., Van Seters, T., Bowers, R. and Drake, J.A. 2021. Winter Maintenance of Permeable Interlocking Concrete Pavement: Evaluating Opportunities to Reduce Road Salt Pollution and Improve Winter Safety. Transportation Research Record, 2675(2), pp.174-186. https://journals.sagepub.com/doi/abs/10.1177/0361198120957320</ref>
**This study conducted at the Kortright Centre in Vaughan, ON. found that permeable pavement (specifically Permeable Interlocking Concrete Pavement - PICP) provides equivalent or higher levels of safety when compared to traditional asphalt when treated with de-icing products. Furthermore, when re-freezing of melted snow and ice occurred durign the evening and overnight black ice was observed on the asphalt, but not the PICP. Overall, it was found PICP surfaces require less de-icer and as a result have a lower risk of slips and falls for pedestrians, when compared to asphalt.
===External Links===
[[File:Smart about salt training.PNG|thumb|500px|Smart About Salt training program teaches winter contracting company staff and facility management staff how to appropriately apply rock salt and still being mindful about its environmental impact, all while reducing reducing liability and maintenance costs. To learn more, click the picture above.<ref>Smart About Salt Council (SASC). n.d. Smart About Salt: Winter Salt Management Program. http://www.smartaboutsalt.com/</ref>|link=http://www.smartaboutsalt.com/training]]
[[File:Smart about salt training.PNG|thumb|500px|Smart About Salt training program teaches winter contracting company staff and facility management staff how to appropriately apply rock salt and still being mindful about its environmental impact, all while reducing reducing liability and maintenance costs. To learn more, click the picture above.<ref>Smart About Salt Council (SASC). n.d. Smart About Salt: Winter Salt Management Program. http://www.smartaboutsalt.com/</ref>|link=http://www.smartaboutsalt.com/training]]
**The purpose of this manual By the Minnesota Pollution Control Agency (MPCA) is to deliver practical advice to those managing parking lots and sidewalks and help make proactive, cost-effective, environmentally conscious choices in winter parking lot and sidewalk management in the State of Minnesota. This knowledge will provide the opportunity to become a leader in the industry by operating more efficiently and reducing environmental impacts. The manual is based on the Minnesota Snow and Ice Control Field Handbook for Snowplow Operators, produced by the Minnesota Local Technical Assistance Program Center, and on the training materials for the MPCA's Winter Maintenance of Parking Lots and Sidewalks training class.
**The purpose of this manual By the Minnesota Pollution Control Agency (MPCA) is to deliver practical advice to those managing parking lots and sidewalks and help make proactive, cost-effective, environmentally conscious choices in winter parking lot and sidewalk management in the State of Minnesota. This knowledge will provide the opportunity to become a leader in the industry by operating more efficiently and reducing environmental impacts. The manual is based on the Minnesota Snow and Ice Control Field Handbook for Snowplow Operators, produced by the Minnesota Local Technical Assistance Program Center, and on the training materials for the MPCA's Winter Maintenance of Parking Lots and Sidewalks training class.
*[https://www.researchgate.net/publication/331991752_A_review_of_the_species_community_and_ecosystem_impacts_of_road_salt_salinisation_in_fresh_waters A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters]. <ref>Hintz, W.D. and Relyea, R.A. 2019. A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters. Freshwater biology, 64(6), pp.1081-1097. https://www.researchgate.net/publication/331991752_A_review_of_the_species_community_and_ecosystem_impacts_of_road_salt_salinisation_in_fresh_waters</ref>.
*[https://www.researchgate.net/publication/331991752_A_review_of_the_species_community_and_ecosystem_impacts_of_road_salt_salinisation_in_fresh_waters A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters].<ref name="example10">Hintz, W.D. and Relyea, R.A. 2019. A review of the species, community, and ecosystem impacts of road salt salinisation in fresh waters. Freshwater biology, 64(6), pp.1081-1097. https://www.researchgate.net/publication/331991752_A_review_of_the_species_community_and_ecosystem_impacts_of_road_salt_salinisation_in_fresh_waters</ref>.
**This study of the impacts of road salt on local ecosystems by Hintz and Relyea (2019), found that road salts negatively affect species at all trophic levels, from biofilms to fish species but the concentration of road salt where adverse effects were observed varied and the effects themselves ranged from reductions in fecundity, size and shape to alterations to nutrient and energy flow at an ecosystem level and increased greenhouse gas emissions from contaminated wetlands and altered hydrology and oxygen, nitrogen and carbon level dynamics in lakes and streams. Concentrations at which road salt triggered an effect varied considerably. To read more about their findings, click the link above.
**This study of the impacts of road salt on local ecosystems by Hintz and Relyea (2019), found that road salts negatively affect species at all trophic levels, from biofilms to fish species but the concentration of road salt where adverse effects were observed varied and the effects themselves ranged from reductions in fecundity, size and shape to alterations to nutrient and energy flow at an ecosystem level and increased greenhouse gas emissions from contaminated wetlands and altered hydrology and oxygen, nitrogen and carbon level dynamics in lakes and streams. Concentrations at which road salt triggered an effect varied considerably. To read more about their findings, click the link above.