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Winter is coming; so is salt. It’s time to develop new weapons in the war against icy roads | Opinion | chroniclejournal.com

HERE IT COMES. Another Northern Ontario winter nears, and with it the perils of driving on ice and snow along with the remedy, namely road salt and all the damage that it brings. After all this time, why hasn’t Canada — presumably a winter expert — figured out an alternative to the road salt products that ruin our vehicles and harm much of our environment?

It turns out that some jurisdictions have done just that with impressive results. First, though, some history.

Road salt initially appeared in the United States when New Hampshire began to experiment with granular sodium chloride in 1938. By the winter of 1941-42, the state began using salt on local roads and highways. Eventually, other states caught on and began using salt to treat their roads, as did Canada.

Water freezes to form ice at zero degrees. Road salt lowers the freezing temperature of the water and stops the formation of ice, but the colder it gets, the higher the concentration of salt that is needed.

Reduced winter highway maintenance in Northern Ontario by private contractors, in part acting on less stringent provincial standards and with fewer resources, has led regional municipal associations to demand more attention sooner after snowfalls as accident rates grow and highways are closed in storms. And so, they poured on more salt.

Today, the United States uses between 10 and 20 million tons of road salt each winter. Canada, with one-tenth the population but just a quarter of the kilometres of roads, uses roughly five million tons of salt products annually.

Writing in the Smithsonian Magazine, Joshua Rapp Learn noted an increasing amount of research showing that road salt gets absorbed into roadside plants, licked up by wildlife or accumulates in aquatic ecosystems — sometimes with devastating consequences. “All that saltiness can help invasive or even toxic species spread, not to mention (ironically) increase traffic danger due to deer and moose drawn to salt-covered roads.”

Among the effects on wildlife, salt runoff into waterways can reduce the size of rainbow trout hatchlings, kill off zooplankton — the minute, abundant organisms that form the baseline resource for entire ecosystems, and even affect gender ratios of frog populations.

Milkweed tends to absorb high concentrations of roadside salt runoff, altering the development of monarch butterflies that feed on it and killing those exposed to the highest levels even as efforts are underway to try and reverse their decline.

Emilie Snell-Rood, an associate professor in ecology, evolution and behaviour at the University of Minnesota, says that since salt is often limited in the natural world for creatures, it can act as a super stimulus when they do encounter it.

“Road salt is kind of like potato chips for animals,” she says. By attracting some species to roadsides, salt can put animals in danger from getting hit from passing cars. Canadians are well acquainted with this phenomenon, some violently so, as moose and deer amble onto highways to lick up salt. Across North America, researchers say there are approximately 45,000 reports of wildlife-vehicle collisions each year.

Salt of course moves from roadside ditches to creeks and rivers and into water tables and lakes, sources of drinking water. High levels of chloride can produce health issues with people on low-sodium diets due to diabetes or other illnesses. The increase in cyanobacteria — also called blue-green algae, which have been growing in number in Thunder Bay district — can also put toxins into lakes people and dogs swim in.

ROAD SALTING has changed over the last 10 years from using rock salt to a heavy wetting agent, or brine that is designed to stick to the road, but conversely also sticks to your vehicle. This new agent “is heavily laden with magnesium chloride which is tremendously caustic to any type of metal,” says Pierre Leger, president of Krown Rust Control. So it’s more important than ever to wash your vehicle after every storm where salt brine is applied to roads.

Even with that, and annual rustproofing, brine will eventually creep into auto body nooks and crannies and begin to rust metal from the inside out. It’s inevitable, but there are ways being found to prevent it.

There are enough harmful effects, including early deterioration of concrete bridges and parking structures and their steel innards, to have prompted some jurisdictions to look at alternatives to road salt.

The Minnesota Department of Transportation has been experimenting with potassium acetate on some of the most heavily used bridges, tunnels and traffic routes near downtown Duluth.

Chris Cheney, maintenance operations superintendent for the department’s Duluth district, said the chemical has shown some promise. It’s better at melting ice in cold temperatures, he said.

Potassium acetate is a liquid solution and costs about three times as much as road salt, Cheney said. But crews are using much less of it than they do road salt, so the cost ends up being about the same. Unlike chloride, the chemical eventually breaks down in the environment.

Following Calgary’s lead, the City of Winnipeg has used beet juice to help lower the amount of salt used on its roadways since 2020, and according to a city spokesperson, it can improve the “adhesion of the sand and salt to the roadway surface at colder temperatures.”

“Beet juice can make up to 60 per cent of the solution we are applying to the roads and is combined with a traditional sodium chloride-based brine. This lessens our chloride loading on infrastructure and the environment while producing a good quality melting solution effective to temperatures below -30 C,” a spokesperson told CTV News.

Yes, the beet juice solution — a waste byproduct of beet sugar refining — does leave the roads stained with red and brown, which can be unappealing. That being said, Laval, one of the earlier adopters of this solution, has started to use the juice from white beets to avoid the mess.

Williams Lake, B.C., began to experiment with Beet 55, a slightly sticky mix of sugar-beet juice and saline. It’s brown and doesn’t stain.

SO WHILE SALT is the cheapest method of winter ice and snow control, it’s also the most damaging. Those withered conifers you see beside highways are brown for a reason.

“We’ve been dramatically increasing the amount of salt per mile since the 1970s, even in places where we don’t have any substantial increases in the amount of road miles,” says Rick Relyea, a professor of biological sciences at New York’s Rensselaer Polytechnic Institute. “The answer isn’t really in alternative salts but in less salt.”

Hilary Dugan, a freshwaters scientist at the University of Wisconsin-Madison, agrees that using less salt is the answer in many cases, and that educating people about the amount they use on their driveways and sidewalks could help. “You can maintain safety by using a lot less road salt,” she says.

Charlottetown uses common-sense ideas to reduce its use of road salt. Sidewalks will not be salted when snow can be scraped to reveal mostly bare sidewalks, when sunny weather conditions and rising temperatures are forecast for after the snow has been plowed, another weather event is expected in the next 24-36 hours, or temperatures are too low for salt to be effective.

The “Superior-By-Nature” City of Thunder Bay, other regional municipalities and the Ontario Ministry of Transportation need to start doing winter differently. Consider the deleterious effects of road salt. Follow the lead of others. Settle on alternatives to protect life. It works.

Salt sensibly this winter - Farm and Dairy

Shorter days, cloudy skies, colorful leaves and frosty nights are telltale signs that autumn is actually and finally here… for now, that is.  Despite the fluctuating temperatures and wacky weather patterns, our region’s beloved (though often cursed!) change of seasons is something that we can always count on. It won’t be long until these falling leaves become falling snowflakes, and we’ll be hanging up the rakes and reaching for the shovels.

No matter the season, what we do on the land affects the quality of our water and no exceptions are made for old man winter. Because the ground is often frozen during this time it acts as an impervious surface, preventing snowmelt and runoff from naturally soaking into the ground and being filtered. In addition, our region’s notorious snowfalls tend to bring with them a heavy dose of salt.

Sodium chloride (NaCl) in the form of crushed rock salt, that is. Since the 1940’s, this road salt has become the most effective and affordable way of keeping our roads clear of snow and ice. Nationwide every winter an average of 20 million tons of road salt are applied to our miles and miles of roads, parking lots, sidewalks and driveways. While usage fluctuates with the severity of the winter, the amount of impervious pavement due to urbanization continues to increase. Though critical to our safety, the cumulative effect of salting roads to keep our society moving has large environmental and economic costs.

Application matters

Throughout 2023, the Geauga Soil and Water Conservation District and other northeast Ohio districts and agencies have been promoting ways to reduce the amount of salt applied through sensible salting strategies. Just like too much salt in your diet can be bad for your health, too much salt on our roads is harmful to our water and soil.

After application, road salt is carried by melting snow and rain into local lakes, streams and groundwater. According to the Ohio Environmental Protection Agency, there is a trend of increasing chloride concentrations in our rivers and lakes across the northern tier of the U.S. and Canada and the long-term environmental impacts of salting our roads is greatly contributing to the alarming salinization of our freshwater.

Salt impacts

Ohio, in fact, now ranks third nationwide for tons of salt applied. Studies confirm that this increased concentration of chloride disrupts freshwater food webs and ecosystems by decreasing zooplankton populations, increasing algae concentrations and negatively impacting fish and insect size and reproduction rates. High concentrations of sodium are fatally toxic to aquatic critters, destroy soil stability, decrease soil’s ability to filter water and increase soil erosion.

When winter precipitation comes to town, roadway snow and ice removal for public safety will always be our first and foremost priority.  After sifting through the many deicing methods and materials, we see that road salt remains king: rock solid for its affordability, abundance and ease of mining, storing, distributing and spreading.

As watershed residents, we know that our daily habits and backyard behaviors inadvertently yet collectively contribute to stormwater pollution. Though we may not be able to control how much salt is put on the roads, we can control our own salting behaviors on our driveways and sidewalks. Simple changes to the amount and ways that we salt can greatly improve the health of our watershed without jeopardizing our safety. The following savvy and sensible salting tips are easy to remember and will help save your money and time.

This winter remember to use the right S.A.L.T.

STUFF — Salt (sodium chloride) only works above 15 degrees F.  For colder temperatures use a small amount of sand for added traction, or switch to an ice-melting product designed to work at colder temperatures. Products containing calcium chloride can melt ice in temperatures as low as -25 degrees F. Remember that chloride in deicers is what burns your pets’ paws and deteriorates concrete.

AMOUNT — Use a gentle hand and spread only enough salt to do the job. One 12-ounce coffee mug full of salt is enough to effectively deice 250 square feet, which is equivalent to about 10 sidewalk squares. Remember that more salt does not mean more melting. Just like fertilizer on your lawn, too much only damages soil and pollutes water. It only takes one teaspoon of road salt to permanently pollute five gallons of water. Also, be sure to sweep up extra salt and sand once the ice melts to ensure it doesn’t wash into a ditch, storm drain, or nearby stream. If it is visible on dry pavement, its job is done.

LOCATION — Spread salt only on the surfaces of your driveway and sidewalk that need to be deiced and never on the lawn, at the base of trees, or near a stream or storm drain. Consider locations where paths through the snow can be created rather than removing all of the snow.

TIME — Salt works best when it is applied right before the snow falls or right after snow is removed from your driveway or sidewalk, and never when rain is in the forecast. Also shoveling and removing snow and ice during a snowstorm reduces the amount of salt required for deicing and increases the efficiency of your efforts.

The old adage says “It takes a village” and when it comes to salting our neighborhoods, we can significantly reduce the negative impacts of sodium chloride within our village with increased awareness and proper application. Armed with knowledge and shovels, it’s time we get smart about salt to secure the necessary safety of both our roadways and waterways.

St. Lawrence Seaway strike stalls road salt, wheat, steel cargo as winter closing nears - The Globe and Mail

A strike by unionized workers on the St. Lawrence Seaway has halted shipments of road salt, Western wheat and steel products amid the yearly rush to move the grain harvest and other key commodities ahead of the winter freeze-up.

The 350 Unifor members stopped work on Sunday after negotiators failed to reach an agreement with the St. Lawrence Seaway Management Corp., the employer that operates 13 of the 15 Seaway locks between Montreal and Lake Erie. The strikers include engineers, skilled tradespeople and supervisors.

The work stoppage has put about 100 vessels at anchor at ports and harbours along the 3,700-kilometre Great Lakes/Seaway system that connects the heart of North America with markets in Europe and Africa.

“Every day, it’s more,” said Gregg Ruhl, chief executive officer of Algoma Central Corp.

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, the largest domestic ship operator on the Great Lakes, with 29 vessels. Seven or eight of these are moored waiting to move goods through the locks.

“That’s a huge impact to Algoma but it’s, more importantly, a huge impact to our customer base,” he said by phone.

Mr. Ruhl said the shipping company is losing $1-million a day in sales, and the economic impact to the overall Seaway industry, including customers, is US$110-million a day.

The strike comes as steel plants in Hamilton and elsewhere on the lakes are stockpiling iron ore pellets that arrive by ship from mines in Quebec and U.S. mines in the upper Great Lakes region. Cities throughout the system are building inventories of road salt from mines in Goderich and Windsor, Ont. And much of the recent grain harvest from the Prairies and parts of Ontario moves through the Seaway.

Shipping lines and their customers have been working to move gasoline, jet fuel, cement, canola and other goods before the locks in the Welland Canal and the St. Lawrence River close for the winter in late December. They will stay closed until late March. Trains and trucks cannot replace the capacity or reach of vessels, and the Port of Churchill in Manitoba is not prepared to replace the Port of Thunder Bay, on Lake Superior.

“The fall harvest time is always the busiest on the Seaway system,” said Chris Heikkinen, CEO of the Port of Thunder Bay, Canada’s second-biggest grain port by shipping volumes and storage capacity after Vancouver. The port continues to load grain and potash, but before long the stream of ships will end because of the closed locks downstream, he said.

“The timing is really bad for us,” said Wade Sobkowich, head of the Western Grain Elevator Association, which represents Viterra, Richardson International and other shippers of Western Canadian grain through Thunder Bay.

Grain companies that cannot deliver wheat and other crops on time face financial penalties, which are eventually passed on to farmers, Mr. Sobkowich said. And the exporters that wait until the spring could receive lower prices than are available now. This is on top of the damage to Canada’s reputation as a reliable source, he said, after a weeks-long strike in the summer closed the Port of Vancouver and other B.C. terminals.

The impact of the Seaway shutdown stretches beyond the borders of Quebec and Ontario, into the Arctic.

Groupe Desgagnés Inc. has four cargo ships en route from the North to Sainte-Catherine, Que., near Montreal. To get to Sainte-Catherine, they’ll need to go through two Seaway locks, which are not being operated because of the strike.

The ships carry vital cargo for individuals, institutions, government entities, private contractors and various other shippers, said David Rivest, president of Desgagnés subsidiary Transarctik Inc. They also carry steel scrap destined for recycling as part of an effort to clean up northern communities.

One of Desgagnés’s ships is scheduled to carry a load of construction and resupply equipment for Canadian Royalties Inc.’s nickel mine in Quebec’s Nunavik region. Even a brief delay in the ship’s schedule could jeopardize its next trip to the Arctic as ice conditions set in, he said.

CSL Group, which operates 17 ships on the Seaway, has anchored the majority of its Great Lakes-Seaway fleet. Crews are staying aboard instead of going home, in order to be ready for the restart, said Allister Paterson, the company’s chief commercial officer. Still, it will take several days to move the waiting ships through the locks when the strike ends.

“Our customers are really worried about what this means,” he said.

“We are really, really hoping that the government gets this back and running and then sorts it out while it’s running because after going through Vancouver shutting down the western gateway two or three months ago, now we’re shutting down the eastern gateway,” Mr. Paterson said.

A representative of the St. Lawrence Seaway Management Corp. did not immediately respond to e-mailed questions on Monday. In a press release on Sunday, the not-for-profit corporation said the two sides were at an impasse over wages. The federal government’s mediation and conciliation office is assisting.

Lana Payne, national director of Unifor, said there have been no talks since the strike began, and none are scheduled. A toxic workplace relationship has contributed to the difficulties in reaching a collective agreement, she said by phone.

The two sides, she said, have “very difficult labour relations in the workplace. And of course, you would see that spilling over into bargaining.”

Industry representatives, meanwhile, urged the government to ensure the company and the union are working toward a settlement, or legislate the union members back to work.

The closing of such a key infrastructure system “shouldn’t be allowed to happen,” said Algoma’s Mr. Ruhl. “You don’t solve disputes by shutting down the main artery of the marine supply chain.”

Catherine Cobden, head of the Canadian Steel Producers Association, said her members need the dispute resolved quickly. “It’s not just about getting the iron ore in. It’s about getting the steel to market,” she said.

Labour Minister Seamus O’Regan said on Monday he has urged both sides to return to the bargaining table, and added that legislation is not the right way to end the strike. Mr. O’Regan told reporters the strike is being closely watched by U.S. officials because of the importance of the shared waterway.

High costs means fewer snowplows on the road the road this winter | Toronto Sun

An association representing snowplow operators is warning many roads and parking lots may not be cleared this coming winter.

Higher fuel costs, skyrocketing insurance and an increase in slip and fall lawsuits is seeing many contractors decide to leave the business.

Landscape Ontario, which represents more than 8,000 small businesses, is warning the Ford government that unless changes are made to legislation and regulations, things will only get worse.

“There is a very real danger that the declining numbers of snow and ice contractors will result in a lack of service for many municipalities and organizations,” the group said in a recent briefing to the province.

Already, some municipalities have had difficulty getting contractors to bid on work. Last winter, the Town of Blue Mountains had to take the clearing of 15 parking lots in-house after no contractors submitted bids.

The problems facing the industry are complex and the result of at times competing interests.

Environmentally, everyone would like to see less salt used in snow and ice clearing operations. Overuse of salt can damage water systems and the land around where the salt is applied, but at the same time clients are demanding that operators use extra salt to avoid situations that could lead to a lawsuit after someone slips and falls on a slippery piece of pavement.

Those lawsuits are part of the reason insurance costs have been rising for snow and ice contractors as well. According to Lanscape Ontario, one company saw insurance rates jump from $70,000 to $234,000 in a single year.

“The availability, capacity, and price of insurance is unstable, and many contractors are being driven out of the industry, and without meaningful change from government, the problem will only get worse,” the association has warned the government.

While insurance costs are going up, fewer companies are offering insurance services to the industry, a problem not restricted to snow removal, but one that drives up costs due to a lack of competition just the same.

Landscape Ontario is asking the Ford government for a couple of changes on this front.

The industry group is asking for the government to work with them on a curriculum and certification program and to establish technical standards for operators. Once they have everyone working on a clear set of standards, they’d like the province to establish limited liability protections to accredited owners, site managers, and snow management contractors.

Without that they say, the industry will remain stuck, open to frivolous lawsuits or lawsuits where what is being claimed is beyond their control due to quickly changing weather conditions or poor site design.

While most major cities perform most of their snow clearing operations in-house, they still contract out parts of it, especially during big storms. Beyond that, smaller municipalities, especially small rural areas, often contract out more of their services.

Without a healthy industry, which would include competition, the cost of clearing snow and ice across Ontario will only go up. That’s if the municipality, shopping mall, church or other organization can even find a contractor.

The Ford government already made some changes in response to concerns of the group in 2020. Whether they can make more changes that will assist them in the short term, to keep operators in the business, remains to be seen.

blilley@postmedia.com

State releases long-awaited road salt report (adirondackexplorer.org)

Maintenance departments must resist bombarding roads of contaminating road salt, fully analyze the need for and effects of salt use and train crews and require certification on best practices, experts assembled by the state suggest, according to information in a new 27-page report.

The state report, embodying much of the work of the Adirondack Road Salt Reduction Task Force set in legislation that initially called for a report two years ago, was released by state officials Tuesday after much anticipation and some frustration from task force members regarding publication delays.

To be delivered to Gov. Kathy Hochul and the Legislature, the report recommends enhanced public funding to achieve goals and objectives. It was backed with a 50-page scientific and technical appendix detailing how salt threatens health and infrastructure.

The main report calls for unspecified sums to achieve ways to reduce salt use during winter months given the documented damage and ill effects of chloride and substances that wash into the Adirondacks’ many waterbodies and corrode facilities and equipment.

The final report comes after demands from participants and environmental activists for it to be produced. It arrives well after the final meeting of the task force of 10 public members plus representatives of the state Department of Environmental Conservation, Department of Transportation, Department of Health and Adirondack Park Agency.

“To implement the recommendations included in this report, additional funding from federal, state, or local governments will be necessary,” it says. “The implementation of best management practices will guide any necessary changes to current snow and ice removal operations, comprehensive planning to institute such changes, and purchasing of equipment for more efficient application of road salt.”

The document lays out the bad things that happen when so much salt is applied in the Adirondacks. It points to a study that questions whether water quality standards are not protective enough to prevent impacts to the Adirondack Park’s sensitive natural resources and ecosystem. 

Besides aiming to protect the park’s water quality, wildlife, and the environment from further potential harm, the study indicates that some residents are threatened by salt runoff, citing “a limited number of instances of regulatory guideline exceedances” found that could result in “impacts to human health.”

“The impacts from road salt on the environment can be long term,” the report says.

“Climate change accelerates our need to find and implement safety practices that protect both public health and the environment,” Health Commissioner Dr. James McDonald said in a press release with the report. “I support thoughtful and practical programs that will further advance our understanding of how best to support the pristine and healthy environment that the Adirondacks provide, now and for decades to come.”

The document says that an estimated 193,000 tons of road salt gets spread each winter over public roads of the Adirondack Park — some 34 tons of road salt per lane-mile of state roads and 13 tons per lane-mile of local roads.

“Once dissolved, about half the road salt applied to roads in winter runs off into surface waters through snow melt and stormwater,” the document says. “The remainder finds its way onto surfaces where, even during warmer months of the year when road salt is not applied, it continues to leach farther into surface and groundwaters.” At least 3,687 miles (28%) of rivers and streams and 820 (7%) lakes and ponds within the Adirondack Park may be tainted by salt runoff from the paved roads.

The task force suggests some pilot programs be studied and more undertaken but also suggests training of public works departments about alternatives and best practices to end frequent and heavy use of salt.

“The goals should be to instill a shared understanding of the need for an effective winter maintenance program, the impacts of excessive road salt applications, bolstering support for road salt reduction measures and alternative removal approaches from a wide set of targeted public audiences, fostering a willingness among the public to support salt management, and garnering support from elected officials to facilitate implementation of best practices, while also considering public safety,” the report states.

The task force recommends that agencies induce road crews to adapt by proving that chloride-free deicing strategies can meet or exceed salt use for safety and performance.

State DOT Commissioner Marie Therese Dominguez and DEC Commissioner Basil Seggos said they look forward to finding a balance between public safety and environmental stewardship. “We are currently evaluating new areas within the Adirondack Park to conduct salt reduction pilot programs this coming winter,” Dominguez said.

The task force suggests that some vegetation management and seasonal speed safety warnings be attempted to go along with alternatives to salt use.

Roadway grading, ditching, brush cutting and tree clearing may allow for snow storage off the paved surface, rerouting drainage of surface runoff and letting in sunlight to increase pavement surface temperatures. These steps alone could reduce reliance on road salt. 

Another idea is for road departments to improve material inventory tracking to understand how much salt and sand is being used, measuring areas for application to understand how much is reasonably needed for a specific roadway and to calibrate equipment accordingly.

The task force said a professional certification program may be wise as a way to deliver training, particularly for  private-sector applicators who may not benefit from training given to public-sector crews. “Offering limited liability protection to trained and certified practitioners who follow prescribed reduced salt best practices could be one tool to incentivize participation,” the report says. 

Task force member Daniel Kelting, Paul Smith College’s interim president, was the only scientist on the panel.

He said he was heartened that much of the science of salt use made it into the report.

The college’s Adirondack Watershed Institute “was first to publish and report the widespread pollution of our invaluable surface and groundwater resources,” he said. “Working with our partners and elected officials we used the science to inform the need to evaluate our use of road salt and to recommend changes in policies and practices to protect our environment and human health.

“Now the hard and necessary work of implementing the many excellent recommendations must begin, we owe it to the waters of the Adirondacks and to future generations who need clean water.”

Sudbury news: City could stop using salt on 73 km of city roads | CTV News

A new report headed to the operations committee next week says new standards and a review of traffic counts means the city can stop using salt to maintain 73.38 kilometres of city roads.

While only a fraction of the 3,620 lane kilometres the city maintains in the winter, it would reduce the amount of salt dumped on local roads by 1,600 metric tonnes a year.

The city uses a combination of sand, brine and salt to maintain streets in the winter. How each road is maintained is determined by what’s known as ‘minimum maintenance standards.’

Those standards are based on how many vehicles travel on the road each day and the posted speed limit. Roads with the highest speed limits and heaviest traffic counts are Class 1, 2 and 3 and are maintained with salt.

Roads Class 4, 5 and 6 are usually only plowed and sanded, with the goal of maintaining them in a “snow packed state,” said a staff report on the plan.

The province issued new maintenance standards in 2018, but before they could be implemented, updated traffic counts for the affected roads in Sudbury had to be completed.

The results of that process mean “several road segments can be converted from salt to sand routes,” the report said.

“For instance, Loachs Road, between Regent Street and Latimer Crescent, that was previously treated with salt … can now be treated with sand,” the report said.

“Reduction in salt use is expected to reduce its impacts on the environment and sources of drinking water.”

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The committee will review the report Aug. 14. The next step after that will be informing the public about the changes and the reasons behind them.

Read the full report here. A list of affected streets can be found here.

Road salt pollution in many US lakes could stabilize at or below thresholds set by the EPA: Lakes have been growing increasingly salty due to road de-icing, but a new analysis suggests with careful action, concentrations may stabilize -- ScienceDaily

Since de-icing with road salt began in the 1930s, the salinity of lakes across much of the US has been steadily increasing, posing a potential threat to aquatic life and drinking water supplies. However, a cautiously optimistic new study in Limnology and Oceanography Letters concludes that if we can hold steady or decrease road salt use, levels in many lakes could stabilize below thresholds set by the US Environmental Protection Agency (EPA).

"For the majority of US lakes, road salt pollution could be a solvable problem, if we put our minds to it," said lead author Chris Solomon, who studies lake ecology at Cary Institute of Ecosystem Studies. However, he cautions that more research is needed to better understand what actually is a safe level of salt in a freshwater ecosystem.

The US applies an estimated 24.5 million tons of road salt on its roads every winter -- mostly in the form of sodium chloride. Rain and melting snow carry this salt into local waterways and aquifers, where it can cause freshwater salinization syndrome. Not only is this salt harmful to many organisms, but it can leach toxic metals and radioactive materials from soil and water pipes.

Solomon saw the upward-trending lines of salt concentrations in US lakes and wanted to find out where they were headed. Would road salt levels continue to rise, or would they stabilize? With colleagues, he developed a model to explore controls on road salt concentration in lakes to reveal the concentration at which they might level off.

The model looked at road density in lake watersheds, the amount of road salt applied per road mile, and precipitation. Hydrologic fluxes were taken into account to predict how salt pollution flows into and out of lakes. The model calculated the levels at which road salt would be expected to stabilize if salt application was held at amounts reported in 2010-2015, for all of the 461,000 lakes and reservoirs larger than 2.5 acres in the contiguous US.

For lakes in areas with light to moderate road density, the authors found that holding road salt application rates steady could help lakes stabilize below 230 mg/l of chloride per liter of water, the threshold designated by the EPA to protect aquatic life. Reducing application could yield additional environmental and economic benefits without threatening road safety.

The authors note that more research is needed to determine if the EPA's 230 mg/l chloride threshold is too high. Solomon explains, "The EPA's chronic toxicity thresholds for chloride were developed with limited data, and there is growing evidence that negative impacts can occur at concentrations well below 230 mg/l." Even less is known about how salt mixtures from multiple sources affect aquatic life.

Some places have set much lower chloride guidelines, including 150 mg/L in Michigan and 120 mg/L in Canada. The model predicts that chloride concentrations will eventually exceed the 120 mg/L threshold in more than 9,000 US lakes, even if road density and salt application rates stay at current levels.

Unsurprisingly, lakes with predicted salt concentrations in excess of EPA's 230 mg/l thresholds were most common in the Northeast and Midwest. Most vulnerable were lakes with high road density and high road salt application in their watersheds. They included some 9-10% of lakes in Illinois and Ohio, as well as a smaller percentage of lakes (<0.1 to 1%) in Indiana, Iowa, Kansas, Michigan, Minnesota, New York, Pennsylvania, and Wisconsin.

Achieving safe salt levels in these lakes will require reductions in salt use. This can be done safely by adopting best management practices and new technologies.

As a test of the model's accuracy, predictions were compared to measurements taken at Mirror Lake in New Hampshire, a site that has been monitored since 1967 by Cary Institute founder Gene E. Likens. After plugging in the local data, the model predicted maximum and minimum salt levels, and the real-world measurements fell within the predicted range. "This gives us confidence that we're in the right ballpark," said Solomon.

"We don't think the model is perfect. It's a simple model that's meant as a tool for thinking through the problem," Solomon says. Among other things, the model ignores salt inputs from natural rock weathering and from human activities like agriculture and industry, and does not consider temporary seasonal spikes in chloride. "We hope others will elaborate on the approach and make better predictions. But in the meantime our results suggest that efforts to control salt application can make a big difference, and may help to prioritize those efforts," Solomon concludes.

Next steps include comparing the model's predictions to observed data in other places where salt application and lake chloride levels have been documented for many years, and using the model to explore how other forms of global change -- such as land use or climate change -- alter both precipitation and the need for road salt application.

US Lakes' Road Salt Pollution May Meet EPA Thresholds | Mirage News

Since de-icing with road salt began in the 1930s, the salinity of lakes across much of the US has been steadily increasing, posing a potential threat to aquatic life and drinking water supplies. However, a cautiously optimistic new study in Limnology and Oceanography Letters concludes that if we can hold steady or decrease road salt use, levels in many lakes could stabilize below thresholds set by the US Environmental Protection Agency (EPA).

"For the majority of US lakes, road salt pollution could be a solvable problem, if we put our minds to it," said lead author Chris Solomon, who studies lake ecology at Cary Institute of Ecosystem Studies. However, he cautions that more research is needed to better understand what actually is a safe level of salt in a freshwater ecosystem.

The US applies an estimated 24.5 million tons of road salt on its roads every winter — mostly in the form of sodium chloride. Rain and melting snow carry this salt into local waterways and aquifers, where it can cause freshwater salinization syndrome. Not only is this salt harmful to many organisms, but it can leach toxic metals and radioactive materials from soil and water pipes.

Solomon saw the upward-trending lines of salt concentrations in US lakes and wanted to find out where they were headed. Would road salt levels continue to rise, or would they stabilize? With colleagues, he developed a model to explore controls on road salt concentration in lakes to reveal the concentration at which they might level off.

The model looked at road density in lake watersheds, the amount of road salt applied per road mile, and precipitation. Hydrologic fluxes were taken into account to predict how salt pollution flows into and out of lakes. The model calculated the levels at which road salt would be expected to stabilize if salt application was held at amounts reported in 2010-2015, for all of the 461,000 lakes and reservoirs larger than 2.5 acres in the contiguous US.

For lakes in areas with light to moderate road density, the authors found that holding road salt application rates steady could help lakes stabilize below 230 mg/l of chloride per liter of water, the threshold designated by the EPA to protect aquatic life. Reducing application could yield additional environmental and economic benefits without threatening road safety.

The authors note that more research is needed to determine if the EPA's 230 mg/l chloride threshold is too high. Solomon explains, "The EPA's chronic toxicity thresholds for chloride were developed with limited data, and there is growing evidence that negative impacts can occur at concentrations well below 230 mg/l." Even less is known about how salt mixtures from multiple sources affect aquatic life.

Some places have set much lower chloride guidelines, including 150 mg/L in Michigan and 120 mg/L in Canada. The model predicts that chloride concentrations will eventually exceed the 120 mg/L threshold in more than 9,000 US lakes, even if road density and salt application rates stay at current levels.

Unsurprisingly, lakes with predicted salt concentrations in excess of EPA's 230 mg/l thresholds were most common in the Northeast and Midwest. Most vulnerable were lakes with high road density and high road salt application in their watersheds. They included some 9-10% of lakes in Illinois and Ohio, as well as a smaller percentage of lakes (

Achieving safe salt levels in these lakes will require reductions in salt use. This can be done safely by adopting best management practices and new technologies.

As a test of the model's accuracy, predictions were compared to measurements taken at Mirror Lake in New Hampshire, a site that has been monitored since 1967 by Cary Institute founder Gene E. Likens. After plugging in the local data, the model predicted maximum and minimum salt levels, and the real-world measurements fell within the predicted range. "This gives us confidence that we're in the right ballpark," said Solomon.

"We don't think the model is perfect. It's a simple model that's meant as a tool for thinking through the problem," Solomon says. Among other things, the model ignores salt inputs from natural rock weathering and from human activities like agriculture and industry, and does not consider temporary seasonal spikes in chloride. "We hope others will elaborate on the approach and make better predictions. But in the meantime our results suggest that efforts to control salt application can make a big difference, and may help to prioritize those efforts," Solomon concludes.

Next steps include comparing the model's predictions to observed data in other places where salt application and lake chloride levels have been documented for many years, and using the model to explore how other forms of global change — such as land use or climate change — alter both precipitation and the need for road salt application.

Citation

Solomon, C.T., Dugan, H.A., Hintz, W.D., Jones, S.E. (2023). Upper limits for road salt pollution in lakes. Limnology and Oceanography Letters.

Investigators

Christopher T. Solomon - Cary Institute of Ecosystem Studies

Hilary A. Dugan - University of Wisconsin–Madison

William D. Hintz - The University of Toledo

Stuart E. Jones - University of Notre Dame

This research is based on work supported in part by the National Science Foundation.

Cary Institute of Ecosystem Studies is an independent nonprofit center for environmental research. Since 1983, our scientists have been investigating the complex interactions that govern the natural world and the impacts of climate change on these systems. Our findings lead to more effective resource management, policy actions, and environmental literacy. Staff are global experts in the ecology of: cities, disease, forests, and freshwater.

Gravenhurst Council acknowledges the dangers of road salt to lake eco systems - The Bay 88.7FM #WeAreMuskoka (muskokaradio.com)

Gravenhurst Council approved the proposal to acknowledge the impact of road salt on lake eco systems, in the July 18, 2023, meeting.

Joanne Smith, representative of the Gull and Silver Lakes Associations, presented the proposal, in collaboration with the Muskoka Watershed Council (MWC), that Council, “pass a resolution acknowledging the impact of road salt on fresh water eco systems, direct staff to produce an annual report with the quantity of road salt used each winter, have a volunteer program for private road salt operators, and become an example of the issue.”

Smith indicated that road salt is an issue because it’s considered toxic according to the Environmental Protection Act due to the damage it causes the environment.

Dr. Norm Yan, member of the MWC, added that sodium chloride levels have increased in Lake Muskoka, according to reports by the Ministry of Environment, Ministry of Natural Resources, and the District over the past 40 years. He said, “There’s 13,000 tons of road salt sitting in the lake.” He compared it to dump trucks backing up and filling it with salt.

Yan advised that the dangerous levels of salt in many of the lakes in Muskoka has a negative impact on the plants, animals, invertebrates, and fish. He indicated that the lakes with the highest salt levels are the ones near winter-maintained roads.

Mayor, Heidi Lorenz, advised that Council needs more time to consider the request further.

Councillor, Penny Varney, expressed shock about the salt levels going into the watershed. She suggested that Council pass the resolution in an effort to acknowledge the impact and to “commit the Town to reduce as much as possible.”

Councillor, Sandy Cairns, a volunteer with the watershed group and who takes water samples, said “it’s astonishing” regarding the salt levels, going into Gull Lake. She added, “The amount of salt coming from five outlets into Gull Lake is atrocious. I’m very concerned about Jevins Lake too.”

Cairns expressed the importance of road safety as a priority, however, emphasized the importance of either replacing or reducing the use of salt. “We have a lot to learn,” she said, suggesting that people are using too much salt on residences too, such as on driveways.

Smith advised that only a tablespoon of salt is needed per square meter, “the size of an umbrella,” and that only a cup is needed for 20 square meters.

Cairns added, “A lot of us think more is better and it’s not.” She referenced sidewalks, with “grains of salt every centimetre, and sliding on grains of salt is a hazard of itself.”

Lorenz requested that Council defer the proposal so that staff can review it and decide. She said, “The District is responsible for less than 10% in the community. I don’t want to make a declaration for something we can’t do… We’re not going to be spreading salt within a few months.”

Varney advised that the resolution “acknowledges the impact on the eco system is all they’re asking right now.” She added, “It’s just education.”

Cairns indicated that even the government acknowledges the toxicity of salt in the waters as “truth.”

Councillor, Peter Johnston, suggested they can still get information from staff, such as the quantity of salt being used. He said, “What we can do is being done,” and indicated the resolution “doesn’t ask for anything except commitment. One reason why we’re where we are today is because good-intended government delay things.”

Johnston added, “We’re in trouble. We’re making great progress… Passing the resolution just shows our commitment.” He suggested the importance of letting the public know they are listening.

Councillor, Randy Jorgensen, suggested that looking at the use of other options for the roads can also lead to lower costs. He added, “The plan is how to do better. We already are committed to doing it. So, there’s potential for a financial benefit.”

Lorenz advised, “If the proposal fails it can’t be brought back for 6 months.”

Smith said, “We’re just asking to reduce salt as mush as possible.”

Majority of Council members voted in favour of the proposal, acknowledging the toxic threats and environmental damage of salt and less use where feasible.

Report warned road salt more environmentally harmful than fracking | News | westernstandard.news

The Environment Minister Steven Guilbeault’s department said they do not know how much harm road salt, a contaminant used in Canada, has caused the environment. 

Even though it is considered a more significant threat to the environment than fracking, the exact extent of the damage caused by large amounts of road salt used yearly, especially in Ontario and Quebec, is still unknown.

“Salt application for de-icing purposes has been recognized as a major source of contamination,” said a department report. 

“There is still room for improvement.”

According to Blacklock’s Reporter, the department in 1995 placed road salt on a “priority substance list” but stopped short of listing it as toxic. Federal research in 2001 concluded salt posed a risk to “plants, animals, birds, fish and lake stream ecosystems and groundwater.”

“Canada is the largest consumer of salt in the world mainly due to the demand for road salt for de-icing roads in winter conditions,” said the new report Review of Progress: Code of Practice for the Environmental Management of Road Salts. 

“Approximately 90% to 95% of Canada’s salt consumption is for de-icing and chemical production.”

At least 4.9 million tonnes of road salt were dumped annually, almost all of it in Ontario. The department complained it was “difficult to evaluate the quantity” since Québec does not report figures. The last data from Québec in 2017 put usage in the province at 1.5 million tonnes a year.

According to the report, it is known that salt can harm lakes, rivers, and groundwater, but we are unsure of how widespread the contamination is.

“There are no comprehensive studies on chloride concentrations across Canada,” said Road Salts. 

“Many recent studies investigating long-term trends in chloride concentrations in certain North American freshwater ecosystems have shown increasing chloride concentrations.”

Researchers wrote that municipalities used too much road salt without considering public safety or harm to the environment.

“There is a societal expectation of bare pavement and sidewalks throughout winter,” said Road Salts. 

“Decisions around the application of salt, including how much to apply, are often driven by the perception of risk and liability and may lead to oversalting.”

A 2013 Access to Information report from the department of Natural Resources found that road salt, farm fertilizers, and other common chemicals pose a higher environmental risk than shale gas fracking.

“In Canada, surface activities have been identified as posing the largest risks to groundwater, for example municipal landfills, industrial waste disposal sites, leaking gasoline storage tanks, leaking septic tanks, accidental spills, runoff from road salt, fertilizer, pesticides, livestock wastes etcetera,” said the report.

“Hydraulic fracturing using the technologies employed in Canada and governed by Canadian regulatory requirements has not resulted in significant negative environmental impacts,” said the report Shale Gas Development in Canada: An NRCan Perspective.