News

Salty decision: Why the City of Barrie will be sprinkling more salt than normal on roads this winter (simcoe.com)

You may find the decision a bit abrasive, but the City of Barrie was left with few options.

The deteriorating condition of the Ferndale Drive North operations centre sand dome has forced the municipality to rethink its winter maintenance plans for road infrastructure.

Operations director Dave Friary says a structural inspection of the dome, carried out in the fall, revealed the building could not be used to store sand this season.

Instead, sand will be swapped for salt during more moderate temperatures at the beginning and end of winter. Salt will be used at low application only when required, to minimize environmental implications, he said.

“The trucks are all computerized now; they have spin rates and it cuts down on the amount we put down,” Friary said. “The last thing we want to do is contaminate (Kempenfelt) Bay.”

As salt supply depletes this winter, room will open for sand in an operations centre storage building, he said.

Typically, residential roads are maintained to snow-packed condition by plowing, then applying sand for traction.

But sand has limited effectiveness because it often blows off roads quickly. And high levels of chloride, one of the main components in winter salt, has become an issue in watersheds across northeastern North America, Lake Simcoe Region Conservation Authority environmental science and monitoring manager David Lembcke said.

“Barrie is very savvy with their winter maintenance,” he said. “They recognize anything you put down has an impact. There’s a bit of a ‘damned if you do, damned if you don’t.’  It’s juggling human safety versus environmental impact.”

Lembcke said chloride concentration in the lake has increased by .7 mg/L annually since 1971. And 81 per cent of all salt entering Simcoe comes off roads.

Salt concentration above the 120 mg/L threshold can affect the health of some sensitive freshwater species; 640 mg/L will kill many of those off altogether. Many urban creeks already exceed the first number throughout most of the winter and can surpass the second after melting events. 

Municipalities are more frequently applying less-salty anti-icing and brining techniques in advance of storms.

But climate change, and expanding road infrastructure from population growth, often offset those efforts.

“If we expect I can go out on bare roads an hour after snowfall, that puts unbelievable strain on winter maintenance,” Lembcke said.

The city’s plan also means a street-sweeping recycling program, where sand is reclaimed and reused at a roughly $200,000 annual cost savings to the municipality, has been suspended indefinitely. It also didn’t run last year.

Dieter Mueller, who ran unsuccessfully for a councillor seat in the recent municipal election, has long advocated for the recycling program to be kiboshed. He alleges it risks exposing residents to heavy metal, asbestos from some stretches of pavement, microplastics and vehicle liquids.

“I guess my message got through to them,” he said. “The amount of contaminants in the sand, once it is swept off the street, is quite high. It becomes dangerous. If it goes back on the street the following winter, it increases. It’s like compound interest.”

Friary disagrees with Mueller’s claim.

“It’s an accepted practice,” Friary said. “We (had) it tested annually and everything works out. It’s environmentally friendly. We take out all the large pieces — the coffee cups, cans (and) sticks. We’re reusing a product, rather than buying clean, virgin sand. We use 75 per cent virgin sand and mix in the street sweepings; it’s not all recycled.”

The city’s new salt plan meets Ontario’s maintenance standards for municipal highways. It is expected to remain in place until the operations yard is redeveloped, likely within two years. An update on the project is expected to be presented to council this spring, he said.

P.E.I. watershed groups urge Islanders to keep road salt away from waterways  | CBC News

Watershed groups on P.E.I. have created education campaigns encouraging Islanders to use less road salt — and keep it out of waterways — because of the impact on animals and the environment. 

The Trout River Environmental Committee (TREC) launched its campaign last week, in partnership with the Wheatley River Improvement Group. 

"The purpose is mostly just to raise awareness of the issue. A lot of people don't know the impacts of road salt, so we wanted to get the word out," said Shayla Steinhoff, project manager for TREC.

"We really want to highlight vulnerable areas, and identifying these vulnerable areas, and then also creating management plans for them."

Steinhoff said vulnerable areas would include water courses and wetlands — areas where road salt run-off is happening, especially off major highways.

"Some mitigation measures could be creating vegetative buffers around roadways," Steinhoff said.

"Decreasing the risk of run-off directly into waterways, as well as making sure that we have good buffer zones around our streams." 

Protecting wildlife

One of the examples in the campaign is the wood frog.

"That would be because of their very thin and delicate membrane, and also the amount of time they spend in the egg," Steinhoff said 

"Road salt contamination can cause a number of different impacts on wood frogs, from them not being in the area, to increased mortality rates or not being able to go through metamorphosis."

Steinhoff said road salt also has an impact on brook trout, birds, plants, soils and mammals. 

"Mammals can often be drawn to the roadside to consume salt and because of this they can be struck by vehicles, the biggest one here being the snowshoe hare," Steinhoff said.

Steinhoff said her group realizes that reducing the use of road salt will take time because it also keeps people safe.

"It's something we need to work on until we have better alternatives that are as cheap as road salt,"Steinhoff said

"It is also something that we wouldn't see the results for a number of years, or decades, just because of the storage of road salt contaminants in groundwater."

Tips for homeowners

The Stratford Area Watershed Improvement Group has also created a social media campaign around the impacts of road salt, including tips for homeowners.

"Try shovelling first, shovelling everything you can. You might realize you don't need as much road salt," said project manager Lily McLaine.

"It's also important to just sprinkle some salt on the icy parts of your driveway, or just around your car, not the entire driveway if that's not necessary." 

"We highly recommend if you live close to a stream, within 100 metres or so, to opt for using sand or a mix of sand and salt for your driveways. You can also opt for other alternatives such as sand mixes and sawdust."

P.E.I. sends an annual update to Environment and Climate Change Canada, reporting its progress on the national code of practice for the environmental management of road salts.

A spokesperson for the P.E.I. Department of Transportation said the province does have a salt management plan that is reviewed after every winter season.

"While P.E.I. does not have a formal inventory or action plan of vulnerable areas identified, we are familiar with the provincial landscape. It should also be noted that only 10 per cent of our Island road network receives road salt."

"We strive to use only the amount necessary to keep the travelling public safe. We receive road forecasts multiple times a day which helps staff determine when, and how much material should be spread."

Credit Valley Conversation Wants You to ‘Salt Responsibly’ | FM101 Orangeville Today

Winter has arrived.

It is the season of driving in the dark to and from work.

Cold, blowing, snowy days, shoveling snow until the piles are higher than an NBA basketball player and sensible winter gripping footwear is a must.

To help the public travel safely winter maintenance chemicals, predominantly sodium chloride often referred to simply as road salt, have been stocked up, and equipment has been calibrated.

The winter maintenance crews are out early preparing sidewalks, parking lots, local roads and highways for safe travelling by the public.

However, there are many impacts from the use of road salt and other winter maintenance chemicals.

They include damage to infrastructure and vehicles, impacts to the environment (land and water) and damages to vegetation and crops.

By ‘Salting Responsibly’ we can balance human safety on our roads, walkways and parking lots with keeping our environment and drinking water sources healthy.

The Lake Simcoe Region Conservation Authority has made great efforts in researching and understanding the impacts of road salt from a watershed perspective.

They found that chloride concentrations are increasing in rivers, streams and within Lake Simcoe itself!

Peel Region using salt wisely to protect the environment, wildlife (mississauga.com)

Peel Region is using salt mindfully this winter and reminding residents to use road and sidewalk salt wisely as well.

Winter road operations in Peel are underway as snow and icy conditions continue, a recent news release stated. Colder nights at or below freezing can cause the formation of ice on the cold pavement, resulting in roads that are less safe for travel.

As snow or freezing rain conditions continue, road and sidewalk crews, parking lot owners and residents apply rock salt. Unfortunately, salt doesn’t disappear when snow and ice melts as it mixes with water from melting snow or rain and ends up in our rivers and lakes. This salt can harm the environment, wildlife, and quality of our drinking water, the release added.

To ensure driver safety and support a healthy environment, Peel Region said it monitors the weather and sends trucks to apply liquid salt brine to roads and bridges, where needed. The water in the brine evaporates and the salt residue leftover forms a barrier to reduce slippery conditions.

Salt brine contains less salt and sticks to the roadway; whereas, solid rock salt, when spread on a dry roadway, will scatter to the edges by moving vehicles and more will have to be applied, the release added. If there is no precipitation, the salt brine stays active on the road for several days.

“We are committed to keeping our roads safe and clear of snow and ice while applying salt responsibly. Peel Region roads operations continue to research new methods and alternatives to help reduce the amount of salt used, while maintaining our bare pavement standards,” said Mark Crawford, manager of road operations and maintenance, transportation and public works for Peel.

“The region has a salt management plan in place that focuses on best practices and techniques to ensure the safety of our residents while minimizing the impacts of salt to the environment.”

Peel Region is asking residents to use salt wisely this winter by sharing the following tips:

• Shovel first. Clear snow from your driveway and walkways as soon as possible.

• Only use salt once the snow is removed in areas needed for safety.

• Only use salt in temperatures above -10 C and try using alternatives such as sand, grit or non-clumping kitty litter when temperatures dip below -10 C.

• Remember salt doesn’t need to be seen to be working.

• Excess salt left on driveways and walkways can be swept up and used another time.

Learn how to manage salt use at home or at commercial properties and what the region is doing to reduce salt use while maintaining safe roads.

The Weather Network - Is road salt hurting salmon? UBC and volunteers are investigating

The potential environmental impacts from road salt have been widely documented, including negative effects on wildlife, so it stands to reason that salmon could be on the receiving end of it.

Could too much road salt in the streams be one of the causes of declining Pacific salmon numbers? Well, that's what the University of British Columbia (UBC) is hoping to determine with absolute certainty.

Researchers Patricia Schulte, Chris Wood and Colin Brauner are leading the initiative, joining forces with community groups to investigate road salt in streams and whether it could be harming Pacific salmon. They are looking into the seasonal impact of road salt in more than 20 streams around the Lower Mainland, as well as growing baby salmon from eggs in high saltwater in the lab.

Road salt can take a toll on vehicles, infrastructure and the environment, mainly from the inevitable melt that occurs in the spring.

"When the ice melts, it washes off the roads and gets into groundwater and runs across the surface into rivers and streams. And it's not like you could taste salt in the streams, but there's enough salt in there that it can be harmful to fish," said Schulte in a recent interview with The Weather Network.

Salt's effects on fish and other wildlife

While not a lot is known about the effects of road salt on Pacific salmon currently, it can stunt the growth of other closely related species such as the Atlantic salmon and the rainbow trout, Schulte said.

"It can reduce their survival and it can just make them generally unhealthy and less successful. So it's a real problem," said Schulte. "Here in B.C...the [Pacific salmon] babies are born in the fall and they grow through the winter as little fish and the salt can harm them at that stage."

It isn't just fish that road salt can negatively impact. It can have different effects on other wildlife, too, she said.

The presence of salt in the water can adversely affect frogs and turtles, while any that accumulates on the side of the roads can be absorbed by plants, which are then eaten by insects such as butterflies, also reducing their survival, Schulte added.

"It can cause like behavioural changes because it kind of messes up their brains a little bit. For birds, for example, the main problem is the actual rock salt when the birds mistake it for grit. Birds like to eat grit because it helps them digest their food," said Schulte. "In birds, even a little bit of salt can be dangerous."

For bigger wildlife such as moose and caribou, they enjoy the taste of salt, which is "like eating potato chips," so it attracts them to the roads where they become exposed to potential vehicle collisions, the UBC researcher said,

"It sort of depends on the animal, on what the effects are. But there are negative effects across lots of different kinds of animals," said Schulte.

Road salt usage in Canada is rising: Schulte

In 2020-21, at least 4.7 million tonnes of road salt was used across the country, according to data provided to The Weather Network from Environment and Climate Change Canada (ECCC). The total doesn't include users not covered by ECCC’s code of practice such as domestic, private or institutional consumers, road organizations using less than 500 tonnes per year and Quebec, since it has its own strategy that records amounts.

In a media release, Schulte said road salt use in Canada is increasing at about 2.5 per cent per year. In Vancouver, B.C., the city has 3,000 tonnes of salt in its yards for winter maintenance on streets and sidewalks.

Of the amount of road salt used in the country in 2020-21, at least 831,242 tonnes of it were documented in B.C., according to ECCC.

While scientists aren't 100 per cent certain road salt is affecting salmon, "we're pretty sure that it is," she said, noting there isn't a lot of monitoring of salt in water in B.C. currently.

However, the observations seen so far suggest that at least some creeks around the Lower Mainland, including in the Metro Vancouver area, have enough salt in the waters to be "occasionally" more than seven times the acute toxic limit, and potentially as much as 28 times beyond the chronic toxic limit, Schulte added.

"That's where long-term exposure could harm the fish. So, we know that at least at some times of the year, the levels are getting high enough that it can be harmful," said Schulte. "We don't know exactly the harms, and it may differ between different kinds of fish."

Part of the issue is that salt doesn't enter the water continuously, but rather in pulses, especially in the Lower Mainland, she said, as it isn't used every day during the winter. "People haven't really studied the effect of these pulses as much. They've more so done a longer-term toxicity [review]," said Schulte.

Volunteers helping UBC uncover the possible impacts

Alan James, a volunteer streamkeeper with the Stoney Creek Environment Committee (SCEC) based in Burnaby, B.C., told The Weather Network recently the group has been examining the salt in the watercourse since 2005.

The committee conducted its own study in the creek by putting salmon eggs in two different parts of it, James said. One section of it was contaminated by salt and the other was clean, with results showing there were differences. The analysis prompted a change in road salt usage from Simon Fraser University, but not all of it has been removed from the ground.

"We've been looking at trying to find ways to deal with that and to understand just what the effect of salt is on the fish. And of course, citizen science is great, but it's not sufficient to move large organizations," said James.

As a streamkeeper, James and his fellow SCEC members do counts of returning salmon in the fall and trap juveniles in the spring to see how many have hatched. The group also conducts studies on stream bugs to see what different species are in the watercourse -- indicative of its health, he noted.

"That will be something that is part of what we have been doing for some time as streamkeeping groups," said James. "We will add that information in a more co-ordinated fashion to the work that Tricia [Schulte] and others are doing at UBC, Simon Fraser and BCIT [British Columbia Institute of Technology]."

Citizen scientists and volunteer groups such as SCEC gives UBC researchers the "boots on the ground experience" in terms of what's happening now, James said.

"[While] the largest issue is the road salt that's put [out] by large organizations [and] municipalities...there is a large amount of road salt that gets put into the creeks from private residences," said James. "So, shovel first, use less salt [and] sweeping up afterwards can reduce the amount of salt that gets into the environment."

How we can 'use it better'

Schulte cited a number of things we can do to help reduce salt usage in the winter. For example, we can use the same road salt we've always been employing, "but use it better."

"Store it more securely, so that it doesn't drain away from the storage areas. Use it less because usually [you] put on more than you really need. And only use it when it's really going to be helpful," said Schulte.

Other tips from UBC include:

• You can use sand, which is more environmentally friendly, and grit
• You can use other formulations including pet-friendly salts, which are thought to be less dangerous for animals, including salmon
• When you’re salting your driveway, don’t put the road salt in clumps. Spread it out to achieve the same effect while using less salt

You can find other environmentally friendly alternatives to road salt, here.

"There [are] a variety of things you can do, depending on the extent of the problem. And that's actually part of what we're trying to figure out in this research...just exactly how big is the problem," said Schulte.

"If the amount of salt we're using is not too terrible, then probably small adjustments in what we're doing will be fine. But if it's really bad, then we have to make bigger changes."

Just Beet It on Michigan Roads this Winter - Screamin Scott (wrif.com)

The Michigan Department of Transportation is cutting back on road salt. The solution: beet juice.

Officials say using beet juice instead of salt helps maintain the ecosystem, and protects the infrastructure while treating the roads. Just Beet-it , Beet-it. But ask yourself Beets? I didn’t like them as a kid. My dog got healthy eating my beets instead of me. Would this work on a Michigan Winter?

What science is telling us is a mixture of beet juice and salt helps the roads and works in colder temperatures when it reaches 5 above degrees. No, it doesn’t help lower your blood pressure but when you think of it. If the roads are better that would lower my blood pressure.  So no worries we are not getting rid of salt. We live on top of one of the largest salt deposits in the world. Using less salt will also help our roads, bridges, and cars last longer. They have tried this for years in Canada with great success and it’s cost-effective.  Still won’t be eating many beets in the future but will give it a try on the roads. Hope it doesn’t stain the roads or cars.

Inside the Effort to Reduce Road Salt Amounts in Connecticut – NBC Connecticut

With snow and ice now on the ground in New England, salt is not far behind. It is used to keep Connecticut's road ways safe during the winter, but too much road salt comes with consequences.

“It performs this function, it works well for many things that we use it for, but it has environmental consequences that are very hard to deal with," said Dr. Michael Dietz, an extension educator at the University of Connecticut. "Once it gets into our soil and our aquatic system, it is hard to get it out.”

Dietz, along with a team of researchers, has been looking into the effects of road salt for years. He said research shows that excessive road salt negatively impacts infrastructure, aquatic life, and humans.

"We obviously drink water and many of us, in rural parts of Connecticut, rely on well water. The salt travels very easily through the soil, it gets down into the groundwater, and becomes a big problem for people who have wells that draw that water from our aquifers," explained Dietz.

While too much road salt can cause problems, Dietz also points out that there is no better alternative to take the place of road salt right now.

“Until some miracle product comes around the only way we can address this problem is to reduce what is being applied, but still keep the roads safe," said Dietz.

That is where the Connecticut Green Snow Pro Training comes into play. The CT Training and Technical Assistance Center at UConn began hosting the training in 2018 and has since trained nearly half of the state's cities in towns in best practices for salt application.

“We talk to them about how using less actually can be more impactful to the winter operation and to make the road safer," said Mary McCarthy, director of training at the center.

Along with best practices, the class focuses on maintenance of facilities and equipment. Operators learn more about how salt works and how best to calibrate equipment so that they are applying salt at the proper time and rate.

The facilities team for the University of Connecticut took the course. They went from using about 5,300 tons of salt per year in 2017 to, now, using about 2,100 tons of salt per year.

“We are using half the amount of salt so it is not going into the streams, it is not going into the rivers. It is important because it just saves money across the board. It saves money on repairs. It is better for everyone’s vehicles, our own vehicles," said Wesley Ayers, manager of landscape services for the university. "It is just a money saver and better for the environment.”

The CT Green Snow Pro Training is now expanding. Recent legislation allotted the team seed funding that has enabled them to hire for a new position and offer the course to private commercial applicators as well.

"It is not just the roadways that are receiving the salt application. There are the parking lots, the residential communities," said Shannon O'Loughlin, an educational program coordinator working with the Green Snow Pro program. "We are just trying to cast our net and reach as many individuals that are working in winter operations and maintaining our roadways, parking lots, and sidewalks."

To learn more about the Green Snow Pro Training and other resources to maintain sustainable winter operations, click here.

“We are moving in the right direction and hopefully we can make a significant impact on this issue," said Dietz.

As Salt Coats Snowy Roadways In Winter, Freshwater Ecosystems Pay a Heavy Price | Audubon

The titanic Whiteface Mountain looms over the Village of Lake Placid, a light snow dusting the peak by early October. The smooth surface of Mirror Lake reflects the tranquil autumn scene, but beneath is a problem that’s weighed heavily in this densely-forested upstate New York region.

Come winter, crews cover streets with road salt, which, sooner or later, washes into the lake. In 2014 scientists learned the lake’s chloride concentration—an indicator of salt pollution—was almost 160 times higher than Adirondack lakes without nearby paved roads. Heavier than freshwater, a briny layer accumulated at the bottom, says Brendan Wiltse, senior research scientist at the Adirondack Watershed Institute. This impeded the regular mixing of oxygen, he says, stifling fish such as lake trout and other aquatic life. 

Around the United States, scientists are increasingly worried about rising levels of salt in freshwater wetlands, rivers, and lakes, even in much larger bodies like the Great Lakes. “Essentially, we’re blanketing the Earth with salt,” says Bill Hintz, an ecologist at University of Toledo’s Lake Erie Center. 

Sodium chloride or rock salt, a rough version of table salt, is the most common deicing salt. It works by lowering water’s freezing point, melting snow and ice more quickly. Relatively cheap and proven to drastically reduce accidents, salts have been applied liberally on roads, parking lots, and sidewalks for decades. In snowy regions, home to about 70 percent of the U.S. population, road salt use has almost tripled since the 1970s. 

The costs have become clear. In 2005 University of Maryland geologist Sujay Kaushal co-authored one of the first studies to sound the alarm, predicting that many surface waters in the Northeast could become toxic for freshwater life and human consumption within the next century. Road salt is a major cause of what he calls salinization syndrome, but fertilizer, wastewater, and mining-related salts are other big contributors. “We rely on salts for just about everything,” says Kaushal. Climate change adds to the burden, causing sea-level rise that pushes salt inland and worsening droughts that intensify evaporation. 

Current safety levels may not be enough to protect sensitive freshwater organisms, especially those at lower rungs of food chains that birds and other wildlife rely on. In a 2022 study Hintz and an international team of scientists showed that, at a majority of 16 sites, more than half of zooplankton populations died off when chloride levels were at or below thresholds established in Europe, Canada, and the United States. Almost half the sites also saw increases in algae, which consume precious oxygen, block sunlight to plants below, and can grow into harmful blooms. 

“When these freshwater ecosystems reach a certain chloride concentration, we see a lot of different sensitive organisms disappear from those systems and that triggers ecological change,” Hintz says. Aquatic plants and insects such as mayflies, freshwater crustaceans, and frogs are also vulnerable. 

Each ecosystem responds differently. But the U.S. EPA’s chloride threshold—a non-binding recommendation created in the 1980s and twice as high as Canada’s—applies to all. “What we need to do is lower those thresholds for a lot of lakes and understand the regional context that contributes to species decline in those areas,” Hintz says.

In some places, saltier wells, reservoirs, and other drinking water sources raise the stakes, especially for people on sodium-restricted diets. And once salinization takes hold, it can take decades to undo. Salt-related corrosion also damages infrastructure—cars, bridges, and pipes—and mobilizes toxic metals like lead and mercury. Victoria Kelly, environmental monitoring program manager at the Cary Institute of Ecosystem Studies, points to one example with dramatic consequences: In 2014, the city of Flint, Michigan, switched its drinking water supply to the Flint River, where chloride levels were higher than its previous source, Lake Huron. When corrosion inhibitors weren’t used, lead and other contaminants began to show up in the city’s drinking water, triggering a health crisis. 

Today there are few inexpensive, nature-friendly alternatives to road salt, says Hintz. That’s why he and other experts call for officials to invest in best practices that cut salt use and limit pollution, such as pre-treating roads with brine, improving storage to control runoff, and using modern plows. Many cities and states, including Wisconsin and Minnesota, are already taking action. 

A few years ago, towns and villages around Mirror Lake began to reduce salt use, and environmental groups spearheaded efforts asking residents and businesses to chip in. This year, testing revealed progress: Mirror Lake turned over in the spring—meaning its bottom waters mixed with the surface—for only the second time since 2016. “The lake is mixing more than it was in the past as a result of salt reductions,” says Wiltse. “There’s still a long way to go.” 

As a society, Hintz thinks we need to ask some difficult questions about the price we’ll pay to keep so many paved surfaces snow-and-ice free. It may be time to ask people to drive more slowly or stay home in bad conditions, rather than expect clear roads every winter, he says. No matter what, action is needed now, says Kelly, because ecosystems won’t recover right away: “That legacy effect is going to carry on for years to come.” 

This story originally ran in the Winter 2022 issue as “The Road Salt Conundrum.” To receive our print magazine, become a member by making a donation today.

Snowy Towns are Weaning Themselves Off Road Salt this Winter | Time

This winter’s first snowstorm will be an adjustment for some residents in Davenport, a city of 100,000 on Iowa’s side of the Mississippi river, which averages nearly 30 inches of snow over the season. Like many towns across the U.S. and Canada, Davenport dumps a hefty amount of rock salt across its roadways each year, melting ice and keeping conditions easy for drivers. But this year, residential streets on the northwestern side of town will be left salt-free.

The trial, which may see residents have to drive a few blocks over snowy roads to reach major arteries, is Davenport’s attempt to “find a balance” between road safety and a growing list of problems associated with road salt, says public works director Nicole Gleason.

Ice-free roads may be good for drivers, but scientists warn that salt is seeping into lakes and rivers, including the Mississippi, killing wildlife and posing health risks to humans. Salt also corrodes asphalt and metal, causing some $5 billion in damage each year to roads and cars. And it lures deer and moose onto highways to lick it up, triggering accidents.

And yet, North Americans are addicted to road salt. Road crews have been pouring the stuff in ever greater quantities since the 1950’s, when cars and highways began to proliferate across the region. According to the U.S. Geological Survey, the amount of salt used on U.S. roads ballooned from 1 million tons in 1954, to 10 million tons in 1985, to around 24 million tons a year by 2019, as drivers demanded increasing levels of safety and convenience. “Fifteen years ago, it wasn’t common practice to expect dry pavement after snow,” Gleason says. “But somehow this idea has taken over that everyone should be driving like it’s summer in the winter.”

The quest for an alternative to salt

As the case against road salt has become firmer over the last decade, scientists and local governments have led a quest to find a less harmful alternative. But success has been limited. Chemical solutions have proven expensive and carry their own environmental risks, like decreasing oxygen levels in water or damaging foliage. Sand works for driveways or small areas where it can be easily swept up, but if used on a larger scale, it can clog drains, contribute to fine particle air pollution, or damage vehicles. Cheese brine has been used to melt snow in Milwaukee, Wis., since 2013—handily using up waste from the local dairy industry. But the available quantities only make a small dent in salt needs. Beet juice has proved effective in many places, but it releases sugar into waterways, fuelling harmful algae blooms which are just as dangerous for wildlife as salt is. As a result, it can only really be used as an additive to salt.

“People always want a silver bullet, but this is a multi-dimensional problem with a lot of pieces,” says Xianming Shi, a leading researcher on alternative deicing methods and professor at Washington State University. “I don’t think we will find a magic solution.”

With dreams of fully replacing salt on hold, many states and cities are focusing on reduction. Public information appeals can help. For example, this winter Sudbury, a city of 300,000 in Ontario, is giving out plastic cups in a bid to change residents’ salting habits on driveways. The 12 oz cups, the label notes, hold enough salt to safely de-ice 10 sidewalk squares, or 500 square feet—that’s far less than many people think they need. The cups also remind people not to bother salting when it’s colder than -12°C (10.4°F), because it simply won’t work.

Road crews cut back

Officials are also trying to make it easier for road crews to cut back on salt. Minnesota is a leader here. Since 2016, the state has run a “smart salting” program to train public road crews and private maintenance workers to apply salt without wasting any, helping organizations cut their usage by between 30% and 70% per the state pollution control agency. Minnesota also has policies limiting the deployment of salt on residential streets, like Davenport is trialing. The state’s legislature is now considering a bill that would protect professional salt-appliers and homeowners from legal liability for accidents if they use too little—a factor advocates say has prevented people from using salt sparingly in the past.

The most effective way to cut back on salt may be a more fundamental change in how it’s applied. Spraying brines—roughly one part salt to three parts water—on roads in the hours before snow starts to fall prevents ice from forming in the first place. That proactive approach reduces salt needs by anywhere between 23% and 70%. There are challenges: you need very accurate weather forecasts, and the equipment for mixing and transporting brines is more expensive than for conventional salting. But over the last five years the rising cost of salt and growing awareness of environmental threats has convinced many cities to use brine over salt where possible, including New York, Des Moines and Philadelphia.

For Davenport, which already tries to brine where possible and incorporates 5% beet juice to its deicing solutions to replace some of its salt needs, the next frontier is trying to change public expectations around how clear roads need to be. Judith Lee, the city council member who proposed the trial, says some constituents have expressed anger about the idea of not salting. “They thought we were going to let them slide around on ice, and of course that’s not the case,” she says, noting that road crews will still attend to the trial area if dangerous conditions develop. “But when we talk through all the reasons we want to cut back, people start to understand.”

Shi, the researcher, hopes more local and state governments will find ways to curb their salt addiction. If they can’t, 50 years from now the sodium content of many water sources could reach levels unsafe for human consumption, he warns. “Convenience for this generation—driving from point A to point B fast—could mean our grandkids are drinking salty water.”

Impact of road salt on Cambridge drinking water raising concern - CambridgeToday.ca

The drinking water supply in the city of Cambridge has higher levels of sodium than recommended by Health Canada according to regular water quality reports taken by the region.

The Region of Waterloo website states that regular sodium levels in drinking water should be below 20 mg/L. Anything higher must be reported to public health.

A major cause of the increase is the way roads are treated and the type of salt that is used over the winter months. It's an issue the region is working on.

“We have elevated salt in our drinking water supply water,” Eric Hodgins, manager of hydrogeology and water programs for the Region of Waterloo said.

“We’ve been advocating for the protection of the environment and drinking water.”

It's important to note that the 20 mg/L threshold is a low bar, Hodgins says.

It’s primarily a concern for people who suffer from severe hypertension, congestive heart failure or are on a sodium-restricted diet. 

Doctors are made aware when the levels pass the threshold and know to advise patients who would need to consider water sodium levels when it comes to their overall daily intake.

“Everybody should be considering the sodium levels if they need to be concerned,” Hodgins said.

“We’re required to report it to public health. The doctors know in Cambridge that the water is likely exceeding the health threshold because it’s fairly low.”

The region is working on ways to limit the amount of salt that is used on roadways, including the use of a liquid form that requires a lot less volume. The liquid is something the city is already using where possible as rock salt loses it’s effectiveness when it's colder than seven or eight degrees below freezing. Occasionally the city, who is responsible for laying the salt, will use a sand and salt mixture for freezing rain events but that can have negative impacts on storm sewers in urban environments.

“We want to increase the use of this liquid form,” Hodgins said.

“If you put it on in advance of a storm as anti-icing, you’re putting less on the road because when the snow falls, it’s already there. If you’re putting rock on snow, it needs to make it’s way through to the road, as it’s going it’s melting but it needs to get to the pavement. You have to put more on to get it to the road surface. The rock crystals isn’t what melts the ice, the rock has to come in contact with water that breaks crystals down in liquid forms.”

The other issue is cost. Rock salt is the cheapest and the liquid alternative requires the rock to be processed and broken down.

“The mines pump out rock salt and that then needs to be made into the liquid,” Hodgins said.

“It’s not feasible for us to tell transportation to stop putting rock salt down. It’s not an argument we can win, but we can reduce. The liquid form can reduce total output by about half, we've seen it on private parking lots and pilots that have been done.”

The cost increase doesn’t stop with the processing, as different trucks are required to spread a liquid than what are used to spread the crystals.

On top of the need for some residents to be cautious about the sodium levels in the water, salt being pumped into the environment is a hazard for animals and other creatures.

Water Canada points out that excess salt gets washed away into streams and lingers in the soils, groundwater and storm water ponds. 

Birds can eat salt crystals, resulting in dehydration and death. For aquatic animals and organisms, high levels can result in decreased size, limit their ability to reproduce and in high enough concentrations can be lethal. 

Many plants and trees also can’t grow if the conditions are too salty.

It’s currently a tough spot for the region to be in as they grapple with cost, the importance of safety in the form of clear roadways in the winter and managing health concerns and the environment.

What they can’t control is the use of salt on private properties and parking lots, where an excess is often spread due to liability concerns for the owners.

“The parking lots are a totally different issue because there’s no standard they have to meet, they're all operated different based on the contractor,” Hodgins said.

“There's so much more over-application on parking lots. They don’t have the same traffic so they need to put more down to achieve the same outcome. What were seeing is a really significant over application.”

Despite the obstacles, Hodgins is confident there is a solution.

“We’re trying to find out cost differences in our pilot projects of liquid versus rock salt,” he said.

“Our roads team is moving in the right direction.”