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SPECIAL REPORT: CLEAR ROADS, CLEAR ISSUES
Journey into World of Winter Road Maintenance Reveals Concerns, Conflicts, Progress—and a Long-Simmering Dispute in One Massachusetts Town
By Stephen Hochbrunn, NEIWPCC

Sodium chloride works. Spread the salt on a snowy, icy road and what was once slippery and perilous provides grip, safety. Traffic rolls. Students get to school, workers to jobs. Our economy keeps churning. But sodium chloride can also divide.

In Boxford, Mass., residents living near the interstate that runs through the eastern edge of the town have complained for decades about road salt contaminating the private wells that supply their drinking water. They are weary of waiting for a solution.

“What I want to know is a time frame,” said Michael Shapiro at a meeting with town officials on December 2. “Analysis is well and good, but what does it do me if I’m dead and gone? I’m not looking for compensation. I’m looking for clean water.”

Shapiro is among the dozens in Boxford who report disturbing increases in the sodium in their water, and who are pursuing their own proposed solution—a hook-up to adjacent public water supplies—while Boxford officials pursue an aggressive legal strategy to permanently shutter the state’s giant salt shed in town. Shapiro and his cohorts want results, not courtroom delays.

“The enemy is not the state,” he said. “The enemy is the salt that’s contaminating our water.”

New Tools, Old Treatment Sophisticated snowfighting technologies and processes have not diminished the nation’s taste for road salt. Sodium chloride continues to be the mainstay in the winter road maintenance arsenal, raising growing concerns about the environmental impact and spawning conflicts over the effect on drinking water. All photographs by Stephen Hochbrunn, NEIWPCC, except where noted

The tense situation in Boxford is one sign of growing attention being paid around the region to the way we clear roads in winter—and the impact of current practices, particularly on water quality and aquatic life. Key research is underway in NEIWPCC’s member states, and the picture that is emerging is helping to clarify problems and potential solutions. State highway and environmental agencies are exploring innovative approaches to reducing the use of sodium chloride, which is cheap compared to the alternatives—but has long-term effects that make its true cost far higher. And amid unrelenting budget shortfalls, states are trying to control the cost of winter road maintenance, while meeting two pressing and sometimes competing goals.

“The safety of the traveling public is our first and foremost concern,” said John Narowski, an environmental services engineer with Vermont’s Agency of Transportation. “But we also need to respect the natural environment. Striking that balance is easier in some cases than others. But typically it’s a very demanding challenge for us.”

Spend enough time with this subject and one thing becomes clear: there is no single works-for-all ideal solution, except perhaps one. We could all just stay home and off the roads when they are slick. Wouldn’t that be nice—if it were realistic. Not everybody can telecommute. We need passable roads in winter, if only for emergency vehicles. The goal then is to clear highways, streets, and parking lots of ice and snow in the most cost-effective, most environmentally benign manner possible. That makes it sound simple. It is not.

Evolution of a Tradition

On a classically crisp October day, the salt piled high at Patrol Shed 528 near Derry, N. H., signaled the sweetness of fall was temporary; winter was on the way, and New Hampshire’s Department of Transportation was prepared. The salt had been purchased, delivered, stockpiled—and now it stood by, ready to work its magic on the lanes of Interstate 93, which wove through the woods behind the shed and roared with the noise of high-speed travel.

Ready for the Storm Frank Qualey (right), foreman of New Hampshire DOT’s shed in Derry, speaks with assistant foreman Pete Pelletier in front of the shed’s stockpile of road salt.

“On days like this, it’s hard to believe it’s ever going to snow,” said Frank Qualey, shed 528’s plain-talking, avuncular foreman. It was an idle remark—perhaps wishful thinking. For if anyone knew what was coming, it was Qualey. Every winter for decades, he’d been behind the wheel of a snowplow, and shifts could be long. In the shed’s central building, which houses Qualey’s work area and a break room, tattered couches lined the walls; soon they would be beds for exhausted drivers. In a vast garage, hulking vehicles equipped with sophisticated road-clearing systems sat poised and ready. The crew at shed 528 performs maintenance year-round on a 19.8 mile stretch of I-93, but it is in winter when the pace really picks up, when seasonal workers and their trucks are hired to help get snow off the highway. The seasonal crews do the plowing. Qualey and his men handle the other big job.

“The state does the salting,” Qualey said. “There are exceptions, but very few.”

At shed 528, crews take considerable care to efficiently use its sodium chloride—the chemical name for common salt, including typical road salt—but that it is used in volume at all is stunning when you consider its history. Before the Industrial Revolution, salt was rare, precious, and coveted. (Look to our language for evidence; “salary” comes from the Latin for money given to Roman soldiers to buy salt.) But with the advent of the modern, mechanized salt mine, what was precious became plentiful. Sodium chloride became ubiquitous as table salt and as a raw material for thousands of tasks, from preserving food to fixing dye.

Early Adopters The practice of spreading salt in winter caught on early in New England, and over the years, equipment slowly became more advanced. Thankfully, the days of relying on crews to push salt through holes in a truck and onto the road are behind us. Photo courtesy of Maine Department of Transportation

Why it began to be used on icy roads is a matter of chemistry: when mixed with ice, salt dissolves and creates a brine with a lower freezing point than water, thereby melting the ice. On a road, this melting breaks the bond between ice and pavement, turning a solid, slippery surface into a malleable, drivable slush. Couple this ability with the industrial output of salt that made it cheap and available, and you had the seemingly perfect material for deicing roads adored by a car-mad country. In 1941, New Hampshire became the first state to adopt a general road salt policy, and other states soon followed. Rapid expansion of America’s highway system after World War II fueled a flight to the suburbs, and a need to keep traffic moving. According to the Salt Institute, a trade group representing U.S. salt producers, highway salt use doubled every five years during the 1950s and 1960s.

But as use soared, crudeness of the equipment made efficient spreading impossible. As Qualey strolled around his shed’s modern snowfighting arsenal, he remembered working in the early 1970s, driving a truck as coworkers in the back shoved salt down holes and onto the road. The arrival of trucks that mechanically dropped salt onto a spinning spreader improved the application process, but it was not foolproof.

“We had to stop the salt coming out every time the truck stopped,” Qualey said, “and sometimes we’d forget. Then you could have the opposite problem, if you forgot to turn the salt back on.”

Qualey’s fleet now boasts ground speed oriented controllers, which vary the amount of salt that is applied based on how fast a truck is traveling. Whatever the speed, the road gets a uniform treatment—and when a truck is stopped, nothing comes out at all. It is a marvelous innovation that dramatically improves efficiency. But this advancement and others like it have done little to dent overall road salt usage.

Salt Institute data show that in 2008, the amount of sodium chloride sold for use on America’s roads exceeded 22 million tons, well beyond any previous annual total and almost 10 percent of the average amount of salt produced each year worldwide. Road salt sales fluctuate with the weather, and heavy snows in 2008 generated extensive salt use that year—but data from other sources, including the U.S. Geological Survey, show the 2008 number was not out of line with other annual totals posted since a spike in salt sales in 1993. Seen from one angle, a growth in use is nothing to fear, since deicing greatly reduces accidents in winter, and in making roads clear, salt mitigates the financial hit delivered by storms that might otherwise cripple economic activity.

Unfortunately, the chemical makeup that makes salt such an effective deicer also makes it a uniquely persistent presence in the environment.

“We’re in the rather unenviable situation of being a polluter,” said Morton Satin, director of technical and regulatory affairs at the Salt Institute. “Salt pollutes the environment.”

Satin made that admission during a phone interview, in which he was affable and helpful. But how much of an admission was it, really? Virtually every industry pollutes. What matters is the amount and severity of the pollution.

 

Upward Trend This graph from the U.S. Geological Survey’s 2009 report “Chloride in Groundwater and Surface Water in Areas Underlain by the Glacial Aquifer System, Northern United States” shows the growth in road salt use since the early 1990s, which has resulted in more salt being used for deicing than for any other purpose.

Soluble to a Fault

In the language of chemistry, sodium chloride is highly water soluble, meaning it dissolves readily into water— very helpful when the goal is deicing. But high solubility also means much of the salt applied to a road does not hang around as a separate entity after its work is done, waiting to be picked up and sent to a landfill. Instead salt hitches a ride with the slush created by its melting action. Plows and passing traffic push and splash the salty mix to the side of the road, where some lands directly on roadside plants or percolates into the soil where roots reside. And it is there—on the narrow strips of land to the side of a road—where the environmental impact of road salt first came to light.

In the 1950s, several states, including New Hampshire, began to report that thousands of trees along salt-treated roadways were not only looking sickly but were dying. It turned out the trees were absorbing salt through their leaves and needles, and pulling it out of the soil with their roots. The salt was wreaking biological havoc, stunting the growth of roots and stems. It was not pretty, and it was not environmentally innocuous. Roadside plants help to retain and process pollutants that run off roads; kill the plants, and you kill a key part of the natural buffer zone that helps keep pollutants at bay.

Regrettably, salt’s threat to plants did not disappear with other 1950s discoveries like the beehive hairdo. Take a drive today on the scenic stretch of road that winds around the Cascade Lakes in New York State’s Adirondack Park, and you see a gorgeous landscape. But you will not see many trees next to the road, which is heavily salted during the area’s harsh winters.

“What we’ve seen over the last two decades is the slow and systematic disappearance of birch trees between the lake and the highway,” said John Sheehan, communications director for the not-for-profit Adirondack Council. “The blame falls squarely on the road salt-contaminated soil.”

 

Heavy Toll The healthy birch trees that in 1993 lined Cascade Pass in New York’s Adirondack Park (left) had virtually disappeared by 2003 (right). Damage to vegetation is a well-known side effect of the use of road salt, which is heavily applied in the area. Photos courtesy of Adirondack Council

If salt’s impact was confined to the immediate zone of impact next to a road, that would be problem enough. But trouble also occurs when salt-laden water travels beyond the roadside, which happens with or without vegetation loss. Again, chemistry explains: sodium chloride is made up of sodium and chloride ions, and as ions, they carry a charge—sodium, positive; chloride, negative. When salt dissolves in water, the ions go their separate ways. Of the two, sodium ions are less likely to travel far once the water runs off the road, since their positive charge makes them attractive to negatively charged particles in soil. But chloride ions pass right through soil, and though it may take a while, every single bit of chloride ultimately makes its way to a nearby lake, river, or stream. A 2006 study found chloride levels in the Cascade Lakes in the Adirondacks surged 250 percent in the preceding five years, and were 100 to 150 times higher than comparable lakes elsewhere in the park. The Cascade Lakes are not an isolated case.

For years, researchers across the country have detected rising chloride levels in water bodies large and small. A 1987 analysis of data from sources including the National Water Quality Surveillance System found widespread upward trends in chloride levels in streams nationwide. In 2003, the U.S. Geological Survey reported that chloride concentrations in three New England rivers—the Merrimack, Blackstone, and Connecticut—rose steadily in the past century, with significant increases coming after the 1940s, when road salt use began. Chloride increases are also reported in the Great Lakes; federal monitoring shows levels creeping higher slowly but steadily in Lake Michigan.

Sometimes the increases are so striking, they catch scientists’ attention even when their focus is elsewhere. Aquatic biologist Angela Shambaugh said she was not even considering chloride when she began a project shortly after joining Vermont’s Department of Environmental Conservation.

“I was hired by [VT DEC’s] Lake Champlain monitoring program in 2004, and one of my first tasks was to put monitoring data on the lake into a format that was available for the public,” Shambaugh said. “Chloride wasn’t even the point of the monitoring program, phosphorus was. But as I made all these graphs, the chloride changes just popped out.”

Shambaugh’s report on her findings came out in 2008. In 13 of the 18 major tributaries monitored in the lake’s basin since 1990, chloride concentrations had increased significantly. Marked increases were also seen in two-thirds of the open water stations in Lake Champlain monitored from 1992 to 2007.

“Over the course of the monitoring, the concentration in the lake increased three to four milligrams per liter,” Shambaugh said. “In something that is that deep and has that kind of volume—some 25 trillion liters just in the main part of the lake—that is a huge amount of chloride now in the lake that was not there 15 years ago.”

Shambaugh’s report includes summaries of other studies on chloride levels in Vermont and western New York waters, and the researchers consistently found chloride rising and fingered road salt as the culprit. Salt sneaks into the environment via other pathways; research has shown high chloride levels in groundwater beneath landfills, due to leaching of salt in food waste and products such as rubber. Water softeners are another source; a single residential system discharges roughly a pound of salt per day. Even all of us as individuals contribute: if we consume the recommended daily amount of salt, we relieve ourselves of nearly three pounds of chloride every year. But in study after study, deicing gets blamed for driving up chloride levels, which are naturally at a minute level in most waters.

“I knew there was a lot of salt being put on the roads,” Shambaugh said. “But it wasn’t until I started looking at the numbers that I realized it could have such an effect.”

Shambaugh’s statement echoes what has been said for years by Gene Likens, founder of the Cary Institute for Ecosystem Studies in Millbrook, N.Y., and recipient of the 2001 National Medal of Science, the nation’s highest science honor. For more than 45 years, Likens has been looking into the effects of human-induced ecological change in the Hubbard Brook Experimental Forest in the White Mountain National Forest, N.H. Likens and his colleagues at Hubbard Brook were the first scientists to discover acid rain, and his work has earned him enormous respect. In the scientific community, his words matter. And in an article that appeared in September 2005 in the Proceedings of the National Academy of Sciences, those words could not have been more direct.

In the article, Likens summarized analysis that he and a team of researchers conducted using data from streams in Baltimore County, Md.; the Hudson River Valley, N.Y.; and the White Mountains. The findings: “Chloride concentrations are increasing at a rate that threatens the availability of fresh water in the northeastern United States… Our analysis shows that if salinity were to continue to increase at its present rate due to changes in impervious surface coverage and current management practices, many surface waters in the northeastern U.S. would not be potable for human consumption and would become toxic to freshwater life within the next century.”

Coming from a lesser source, such a bold statement might have been seen as alarmist. In this case, it got plenty of notice, as Likens humbly admitted in a phone conversation in October.

Speaking From Experience Gene Likens, a renowned ecologist who has been studying the environmental impacts of road salt for decades, warns of dire consequences if chloride concentrations continue to rise in surface waters. Likens is seen here in a NEIWPCC photo taken during a visit in 2004 to Hubbard Brook Experimental Forest, N.H., where Likens has conducted research for more than 45 years. Photo by Rebecca Weidman, NEIWPCC

“Yes, that picked up a lot of attention,” he said.

In the article, Likens makes it clear that the management practice most responsible for chloride buildups is deicing, and that chlorides from salt use already pose an environmental threat that we ignore at our peril. While the article generated publicity, those who know Likens had heard the warning before, particularly if the subject was Mirror Lake, a small, pristine lake located where Interstate 93 enters the White Mountain National Forest. With help from colleagues, Likens has been studying Mirror Lake since the mid-1960s, collecting chemical samples from the lake and its tributaries.

In a paper published in April 2009 by the journal Water, Air, & Soil Pollution, Likens and Donald Buso, a Cary Institute colleague, described the disturbing trends revealed by their Mirror Lake research. Chloride inputs to the lake from all tributaries climbed from just under 600 kilograms a year in the 1968-1970 period to nearly 2,900 kilograms annually in 2003-2005. Part of the rise is explained by an increase in salt applied to I-93 near Mirror Lake, but New Hampshire’s Department of Transportation muted this impact by spending more than $500,000 on structures to divert salty runoff away from the lake. Likens’s research revealed that most of the chloride now entering Mirror Lake is coming from the salt used on a small town road.

But why should we care about what happens to this tiny lake few will ever see?

“I think most everybody wants to know that,” Likens said. “Well, in 1969, they pushed I-93 right through the drainage basin for Mirror Lake. I fought it and of course lost. So my approach as a scientist was to make the best of the situation and learn what I could. And because we started working on Mirror Lake so long ago, we have a long-term record of information on the lake, its hydrology, its chemistry, its biology. Arguably this little lake is one of the most studied lakes in the world. It was a great place to do a case study on the effects of road salt.”

While runoff from salt-covered roads has tainted Mirror Lake, its water quality remains acceptable. “[The salinization] is not at the point where it’s going to kill all the organisms in the lake or kill people drinking water out of the lake, or anything of that sort,” Likens said. “It’s far below that. We don’t know where it’s going to go in the future, that question is unknown. But that’s not the point. The point is we can carefully study and document how this system becomes salinized and then use that as a model for other areas that may have gone far beyond that level of salinization. That’s what makes it so valuable.”

Undeniable Impact

In their 2009 article, Likens and Buso predicted chloride concentrations in Mirror Lake will rise over the next ten years to more than 6 milligrams per liter (mg/L), more than seven times the level seen in less affected lakes in the area but still, as Likens points out, well below the numerical level that federal and state officials consider to be toxic to aquatic life. In 1988, U.S. EPA issued an analysis stating freshwater aquatic organisms should not be “affected unacceptably if the four-day average concentration of dissolved chloride, when associated with sodium, does not exceed 230 mg/L more than once every three years on the average and if the one-hour average concentration does not exceed 860 mg/L more than once every three years on the average.” In other words, aquatic creatures should be safe as long as their water does not suffer from chronically high chloride levels (indicated by the 230 mg/L measurement) or rare but high acute spikes (the 860 mg/L figure). More than 20 years later, EPA has not budged from those recommendations, which have been adopted by most states, including four of NEIWPCC’s seven member states.

Given these figures and Likens’s prediction for Mirror Lake’s chloride level, talk of a threat to aquatic ecosystems from chloride may seem exaggerated. But look at levels in streams that take a direct hit from salty runoff, and the threat becomes real. Concentrations in a tributary of Mirror Lake have gone as high as 130 mg/L, and surges far higher than that have been reported by researchers elsewhere in the country. A particularly telling sign of the threat came in a USGS report released in late 2009. Using data collected from 1991 to 2004 for USGS’s National Water-Quality Assessment Program, the study examined chloride concentrations in streams and wells in 19 northern states. In more than 40 percent of urban streams tested, researchers found chloride levels above EPA’s recommended criteria to protect aquatic life. By contrast, when they looked at agricultural areas, where road salt use is limited, chloride exceed criteria only 4 percent of the time.

 

Consider too that very minor increases in chloride levels well below EPA’s criteria have been shown to negatively affect the microscopic life at the bottom of the aquatic food chain, allowing salt-tolerant invertebrates to exert dominance and potentially disrupt a fragile food chain. On the other hand, research has revealed that some fish are capable of taking a chloride bath. The Salt Institute cites a study showing that species such as the adult rainbow trout and yellow perch survived well at test conditions involving a concentration of 10,000 mg/L of sodium chloride for 24 hours. The wide range of biological tolerance helps explain why EPA’s criteria have lingered for so many years—how can anyone say at what precise point a chloride level poses a biological problem? Things get more complicated when you realize salt has more than a biological impact in water.

When runoff from road salt use repeatedly reaches a pond or lake, the increased density in the water body may lead to stratification—that is, the salt-heavy water can form a distinct bottom layer that resists mingling with less dense water above. Vermont DEC’s Angela Shambaugh pointed out that some stratification is natural; dive into a lake in summer and you feel it—the water is warm on the surface, but go deeper and you hit water that is colder, heavier, denser. As summer wanes, and the water on top cools, the density difference shrinks, allowing critical mixing to occur.

“You actually will circulate water from the top of the lake to the bottom,” Shambaugh said, “which is really important in a deep lake because it brings nutrients to the surface where they’re needed. If you get a chemical situation set up where that density gradient doesn’t change, you can’t do that mixing.”

A lake that is permanently not mixing is said to be suffering from meromixis—a malevolent-sounding term for a serious problem. Meromictic lakes exist all over the world, and deicing is not the only cause. But it has been a factor, most notably in Irondequoit Bay near Rochester, N.Y., where effects of road salt use led to extreme stratification that only declined after a dramatic cutback in salt applications.

On the malevolence sound gauge, however, meromixis is dwarfed by another term associated with salt use—cyanide. To prevent stored road salt from clumping and becoming difficult to spread, anti-caking agents containing ferrocyanide can be added to prevent salt crystals from combining into unwieldy chunks. The amount added is small, and the aquatic threat less than the name implies; while the cyanide in the agents can interfere with a fish’s breathing mechanism, dilution and rapid dissipation diminish the danger posed by cyanide ions—which is not to say the danger should be ignored. In 2003, EPA formally classified ferric ferrocyanide, a road salt additive otherwise known as Prussian Blue, as one of the cyanides on the Toxic Pollutant List regulated under the Clean Water Act. EPA said that, while it was highly unlikely, the precise conditions could exist to break down Prussian Blue and release highly toxic free cyanide into the environment.

As worrisome as some of these findings are, the truth is the effects of salt-based deicing on the environment go largely unnoticed by non-scientists—though one is hard to miss. Roadsides throughout the northern states have taken on a purplish hue in recent years, as the common reed Phragmites Australis has moved into wetlands and formed dense colonies. It is no coincidence that this invasion has occurred where road salt is used.

“Phragmites is more salt-tolerant than a lot of freshwater species,” said Tom Maguire, regional coordinator of the Massachusetts Department of Environmental Protection’s wetlands program. “As soil becomes very saline, Phragmites is able to take more of a toehold. So in a lot of areas that have been impacted more by road salt, we are seeing Phragmites move in and outcompete native plants. That changes the type of wildlife habitat that is available.”

A change that can be seen is far more tangible to the average person than data about road salt’s impact below ground and in water. But more purple flowers in roadside wetlands are no more likely than rising chloride levels in streams to get the driving public to take more than a passing interest in road salt use. When the remnants of salt use appear to be coming out of the tap, it is a different story.

Center of the Debate

In Massachusetts, conflicts over road salt and its impact on drinking water supplies have arisen periodically for many years, most notably in Cambridge, the densely populated city near Boston that is home to Harvard and M.I.T. Cambridge gets its water from two reservoirs, both located next to heavily traveled Route 128 and both susceptible to salt contamination. A steady drum of complaints from Cambridge about salt’s impact has led to multiple efforts over many years to reduce the salt load to the reservoirs. The problem has not gone away.

“Every time it snows or there’s an ice storm, and they have to apply deicing agents to the roadway surface,” MassDEP’s Maguire said, “there is still loading, though it’s at a reduced rate.”

Another ongoing issue exists in affluent Andover, Mass., where town officials are pushing to get a road salt storage shed moved out of the town’s watershed district. But in Massachusetts, the place where the conflict over salt use is seen most clearly—and where the battle is being waged most contentiously—is unquestionably Boxford.

Conflict's Epicenter Tensions over alleged road salt contamination of private wells have disturbed some of the peace in the quiet town of Boxford, Mass., where officials are enmeshed in a high-profile legal confrontation with the state.

Located 26 miles north of Boston, Boxford appears quaintly rural—no stoplights, the occasional horse or cow—until the profusion of grandiose homes reveals the town’s foremost identity: a haven for the well-off who want open space and an acceptable drive to Boston. With Interstate 95 slicing vertically through eastern Boxford, commuters have easy access to a route into the city where traffic moves swiftly, whatever the season. But keeping the roughly four-mile stretch of I-95 in Boxford clear in winter has come with a steep cost, according to many town residents who live near the highway.

“It has been a nightmare,” said Karin Rando, speaking in the kitchen of her small, simple home, from which she can look out at her horses grazing on land that backs right up to an on-ramp to I-95. “Moving here was supposed to be heaven. I bought a farm finally. Instead, it’s been a living hell.”

Rando claims her water has been seriously tainted by sodium from road salt, and that she has been the victim of a less-than-sincere effort by authorities to solve the problem. Rando is not alone in her feelings. In Boxford, many people have been feeling the same way for a long time.

“You’ve got state politicians against local politicians, and nobody has the residents’ best interests in mind,” said Bob Eisenberg, who lives a few miles north of Rando and, like her, just west of the highway. “And that’s been the problem since 1974.”

Like most state-owned highways in Massachusetts, the stretch of I-95 in Boxford is maintained by the state’s highway agency, previously called MassHighway but now, after a recent restructuring, known as the Massachusetts Department of Transportation’s Highway Division. (MassHighway is used in this article when referring to the old agency, and Highway Division when referring to the new.) Traditionally, the sodium chloride used to treat I-95 in Boxford and vicinity has come from a salt storage shed just off exit 52 in Boxford. In hindsight, the state might have been better off putting the shed somewhere else. But if you are going to salt roads, you have to store the salt somewhere, and it is hard to deny the lure of putting the shed in Boxford.

In this case, hydrology helps to explain. While sodium is less mobile in the environment than chloride, some sodium ions in highway runoff invariably pass through soil, with the amount depending on the chemical makeup of the soil and the moisture in it. Where the sodium and chloride ions end up depends on many factors, including groundwater gradients and surface topography. But if sodium infiltrates a public water supply—as was the case in Cambridge—it seldom gets a warm reception from the community. (Chloride is not embraced either, but unlike sodium, chloride is not reputed to be a health threat; chloride affects the taste of water and can corrode metal pipes, but most people can consume large amounts of it without harm.)

Since salt sheds have been found to be sources of salty runoff, placing sheds far from lakes and rivers that provide drinking water makes sense. While Boxford is in the watershed of the Ipswich River, from which 13 communities directly withdraw their water, the river itself is a distant presence, just skirting the far southern edge of the town. The closest surface water supply to the shed location is actually a reservoir a full three miles away in the neighboring town of Topsfield. In Boxford, virtually every household gets water from its own private well, so it could have been presumed the wells were deep enough to steer clear of sodium ions. If that was the presumption, it appears to have been very wrong.

Eisenberg said his concerns about road salt use on I-95 stem back to the 1970s, when he saw highway trucks dumping large chunks of leftover salt on the sides of local roads. But for most of his fellow highway abutters, the concerns about water in their wells did not seriously mount until 2004, when a resident desperate for some explanation for severe, recurring headaches got his well water tested—and discovered inordinately high levels of sodium and chloride. The news prompted tests by other homeowners, including Rando.

“My sodium levels have been a bit all over the place, but 2004 was the worst,” she said. “Right now they’re running about 100 [milligrams per liter], but they’ve been as high as 190. And my chloride was up to 490.”

The test results obtained by Rando and her neighbors, many of whom had even higher sodium and chloride levels, got the attention of MassHighway. It offers a salt remediation program through which complaints from well owners are investigated when someone in the home is on a severely salt-restricted diet and the sodium level tops 20 mg/L, or when the chloride concentration exceeds 250 mg/L. Both levels conform precisely with federal and state guidelines, which in chloride’s case are driven by aesthetic concerns, such as taste, odor, or color.

Seeking a Solution Bob Eisenberg and Karin Rando, seen here on Rando’s property in Boxford, have pressed for years for a remedy that brings clean water back to Boxford homes that rely on well water allegedly contaminated by road salt. Interstate 95 lies just beyond the barn in the background.

In short order, a number of Boxford homes were “in the program,” to use Rando’s words, and MassHighway began its carefully defined process for well investigations. Step one: water samples taken monthly for roughly a year to determine the true extent of the contamination and MassHighway’s culpability. That determination governs whether the agency moves on to step two: implementation of measures to remediate a problem. At some Boxford homes, remediation was deemed a necessity.

“Since 2004, MassHighway has put eight holes on my property, from eight feet deep to 400 feet deep,” said Michael Shapiro, who lives on the same street as Rando. Digging a new well that hopefully brings up cleaner water is one of the highway agency’s listed potential remedies—and the one pursued most vehemently in Boxford. But at Shapiro’s home and elsewhere in the town, the search for water with less sodium and chloride often came up empty.

“I’m still using my original well because nothing cleaner has been found,” Shapiro said.

Making matters worse was that the digging on lots at lower elevations apparently drew a salt-contaminated groundwater plume in the direction of the new holes. Shapiro said a MassHighway official admitted this. Eisenberg said a hydrologist confirmed the theory.

“It’s like when you have a bucket of water, and you punch a hole in the bottom,” Eisenberg said. “It accelerated the movement of the plume.”

In Boxford, MassHighway also tried another remedial action—the installation and operation of scavenger wells. Such wells have one purpose: to pull contaminated groundwater out of an aquifer so cleaner water can move in. In its 2006 Snow and Ice Control Generic Environmental Impact Report, MassHighway wrote that in Yarmouth, Mass., a scavenger well pulling up water at 150 gallons per minute around the clock succeeded in removing enough salt in less than a year that sodium concentrations in a public water supply well dropped to normal levels. From what the public could tell in Boxford, however, the scavenger wells met with less success. Newspaper accounts said one well, which was dug on the property of the headache-stricken resident, pulled up 500 tons of salt. That is a big number, but Rando said the impact on well-water sodium levels was small and short-term.

When she spoke, anger about the situation tinged Rando’s remarks. Sadness crept in too. She said a beloved horse had died because of toxic sodium and chloride levels. And she seemed tired of the battle.

“I love my home,” she said. “I love my town. But I want to come home and be able to drink my water, to take a shower and not worry about what it’s doing to my skin.”

Intensification of the Conflict

After years of listening to complaints from well owners and periodically communicating with MassHighway about potential solutions, Boxford officials aggressively stepped into the fray in late 2008. In a letter to MassHighway’s commissioner, Luisa Paiewonsky, the chair of Boxford’s Board of Health wrote that the delivery, loading, and unloading of road salt at the Boxford shed threatened public health because it released salt into the environment. The letter gave MassHighway seven days to shut down the shed or the Board of Health would take “appropriate action.” Eleven days later, a lawyer for the state replied with a letter stating Boxford had no legal right to issue such orders, since MassHighway was created by the state legislature and provided an essential government function, and thereby had sovereign immunity from attempts by municipalities to regulate its actions.

Two days later, on December 3, 2008, Boxford proved it was not bluffing. The Board of Health condemned the salt shed as a health hazard and blocked the entryway. Simultaneously, the town filed a lawsuit in Essex County Superior Court against MassHighway and the Massachusetts Department of Environmental Protection. The suit asked the court to issue an order demanding that MassHighway close the shed, take actions to reduce the health threat posed by salt contamination, and start applying for town permits before digging new wells on residents’ land. As for MassDEP, the suit asked the court to force the environmental agency to institute an enforcement action against MassHighway for storing sodium chloride in a manner and place that could result in groundwater contamination. In response, MassHighway argued that closing the salt shed in Boxford was the more dangerous action, because the forced shutdown prevented I-95 from being safely deiced during storms. And the state’s attorney general (and recently vanquished U.S. Senate candidate) Martha Coakley repeatedly reiterated the sovereign immunity argument and argued for the suit’s dismissal.

Power Play In December 2008 (left), the Board of Health in Boxford, Mass., condemned MassHighway’s salt shed in the town as a threat to public health, and filed a lawsuit against MassHighway and Mass DEP. The shed stood largely empty this winter (right) while the case plays out in court. Photos courtesy of Tri-Town Transcript

Ultimately, the court decided to let MassHighway operate from the salt shed last winter, but the suit still stands, and in June, the court shuttered the shed as Boxford requested. As this issue of IWR went to press, the shed remained off-limits as a site for storing and loading salt—the court evidently not convinced by the Highway Division’s late plea to use the shed for salting operations this winter as well. At the meeting in Boxford of town officials and residents on December 2, 2009, Board of Health chair Dick Taylor said progress had been made.

“In six months, we have essentially stopped the salt shed from operating,” Taylor said. “So in six months, we have achieved more than we did in six years of meeting with MassHighway and writing letters.”

Eisenberg, who was in the crowd, expressed less satisfaction.

“It would be a shame to spend money on a lawsuit just to get the shed closed,” he told the officials. “The salt that’s placed on the highway and percolates into the aquifer is the problem. We’re suggesting a permanent remedy be put into the lawsuit.”

Eisenberg, along with Rando and Shapiro, are among the founding members of the Boxford Watershed Association, which seeks the creation of a separate instrumentality of the state, much like the Massachusetts Water Resources Authority, to deliver a sodium-free public water supply to houses along the salt-affected corridor next to I-95. Working with the area’s state representatives, the association has put the idea into draft legislation that may be placed before the voters of Boxford at a town meeting this spring. Just where the water would come from has yet to be worked out. One idea is to get it from adjacent towns, all of which have public water supplies but may not have much to spare; water restrictions in summer are common in the area, since most towns draw from the frequently flow-challenged Ipswich River.

Another town resident is proposing a different solution. Joseph Pugia wants reverse osmosis water treatment systems installed at each of the three exits off I-95 in Boxford, and in late 2009, he sent a detailed description of his proposal to the Highway Division. He got a reply too, a letter from the division’s chief engineer saying he was open to discussing the idea. But the letter also contained the statement that with regard to Boxford homes with elevated levels of sodium and chloride in their well water, “only a few unresolved cases remain,” hardly a fair assessment and one that raises doubt about the sincerity of the response.

At the December meeting, town officials did not dismiss either proposal, but they said they have no choice but to let the legal process play out, and only then will they focus on a permanent solution. They said more hydrological analysis is needed, but that costs money, and there was no obvious source. When Shapiro asked for a time frame during which a solution might be considered, nobody had a good answer. But based on comments at the meeting by Boxford’s attorney, Mark Reich, more patience will be required. Reich described the discovery process—the exchange of case-relevant documents between the plaintiff and defendants—as frustrating and slow.

“We have yet to have a hearing on the merits of the case,” Reich said. “But we have established that this is a serious public health issue.”

Annual Report In December 2009, one year after the barricading of the salt shed, Boxford attorney Mark Reich (at table, fourth from left) updates town officials and concerned residents on the status of the legal proceedings.

Different Opinions

When Reich made that statement, heads nodded in assent. Not every audience would have been so accepting. Ever since the 1940s, when studies first began revealing the potential health benefits of limiting salt consumption, there have been those who have questioned the connection between sodium and disease. The Salt Institute is outspoken on this point, arguing that recent research shows no increase in heart attacks based on salt intake, and scoffing at the so-called ecologic studies of the 1960s and 1970s, in which researchers linked low levels of cardiovascular disease of indigenous populations such as the Yanomami Indians of Brazil to their largely salt-free diets; in its literature, the Salt Institute points out correctly that a study conducted in 1997 on a tribe in Panama found tribal members who significantly increased their sodium intake showed no signs of higher blood pressure.

But it is not hard to find research supporting the view that when it comes to consuming salt, less is more. That was the finding of the most recent highly publicized study on this issue, published on January 20, 2010, in the New England Journal of Medicine. Researchers found that lowering salt intake would dramatically reduce heart attacks, strokes, and new cases of heart disease in the United States, and would prevent about 100,000 deaths a year.

In the community of environmental regulators, the tendency is understandably to err on the side of caution in situations where consensus on a health or environmental risk is lacking. Analyze all available research, contradictory or not, and ideally make a decision independent of outside influences. In 1976, researchers at EPA took an in-depth look at the health implications of sodium when it appeared in one specific guise, road salt. If readers were expecting a bland, conciliatory document, they were in for a surprise. In the report, “An Economic Analysis of the Environmental Impact of Highway Deicing,” the researchers were unequivocal in their verdict.

“Without a doubt the most serious problem is our water supplies. While the cost of damage to bridge decks and vehicles is high, but reversible, the damage to health may not be reversed. We can no longer afford to ignore the fact that we are depositing large quantities of salt into the water that nature provides us and upon which we are dependent every moment of our lives . . . Disregard for the quality of drinking water in this and any instance is extreme negligence and we must face the issue squarely . . . salt use for winter maintenance must be reduced in many areas.”

One tool at EPA’s disposal to follow this advice and indirectly reduce road salt use was to regulate sodium levels in drinking water supplies. More than two decades after the 1976 report, the agency took a step in that direction. In 1998, EPA included sodium on its first Contaminant Candidate List, which identified unregulated contaminants that could adversely affect human health and were already in public water systems or would likely be moving in soon. Inclusion on the CCL initiated an intensive multi-year review by EPA of studies and data on sodium’s health effects, with the goal of determining if sodium in drinking water should be subject to a legally enforceable limit known as a Maximum Contaminant Level or MCL. In 2003, EPA released a report on its findings.

“After reviewing the best available public health and occurrence information, EPA has made a determination not to regulate sodium,” the report said. “This determination is based on the finding that regulation of sodium may not present a meaningful opportunity for health risk reduction for persons served by public water systems.”

EPA explicitly did not say that drinking sodium-rich water was risk-free; on the contrary, the agency said water with sodium above 120 mg/L could further raise the blood pressure of people with hypertension—that is, people who have high blood pressure to begin with. That sounds ominous, given some 43 million Americans are hypertensive, and the higher the blood pressure, the greater the risk of heart disease and stroke. But EPA downplayed the risk, saying only 8 percent of the U.S. public water system population is exposed to sodium concentrations above 120 mg/L in water, and that people instinctively steer clear of water which tastes salty, something the agency said would occur at sodium concentrations well below the 120 mg/L level.

EPA added that sodium is only one factor among many contributing to high blood pressure, and that furthermore, its presence in water makes up only a small percentage of the sodium a typical person consumes in a day. Taking the regulatory route to reduce water-borne salt, therefore, would likely not do much to reduce hypertension in the population. Far better, EPA said, to encourage exercise and a well-balanced, nutritionally sound diet.

This stance is perfectly reasonable unless you happen already to be at high risk for hypertension, perhaps because of a genetic predisposition. Could not drinking water with an abnormally high level of sodium be the final factor in pushing you over the threshold from healthy to hypertensive? Researchers have long expressed this concern about at-risk individuals, and EPA is not immune to it. While the agency decided not to formally regulate sodium in drinking water, EPA does require public water systems to monitor for sodium and notify local and state public health officials if the level exceeds 20 mg/L. It is hard to imagine officials getting too alarmed by the occasional exceedance, since EPA stresses the level was only set so low due to concerns for people restricted to 500 mg of sodium a day. The average amount of sodium consumed each day by an American male is more than 4,000 milligrams.

Agency Under Scrutiny

In Boxford, Karin Rando said she is among those who must play it very safe with sodium.

“My family history is high in diabetes and high blood pressure,” she said, “so I don’t add salt to anything. I can taste any amount. I’m very cautious.”

Rando is not, however, inclined to caution in conversation. When the subject was the Massachusetts Highway Division, she did not hold back.

“There’s no one policing them,” she said. “They’re policing themselves, which is unbelievably dangerous, the whole absolute power. And we’re the people who suffer for it.”

Rando and others in the Boxford Watershed Association shared numerous stories of MassHighway contractors acting irresponsibly when salting or digging replacement wells, but ascertaining the truth of the stories and the merits of the charge of abuse of authority is a task for the courts or at least an organization with far more investigative resources than NEIWPCC. And even if everything the association members say is true, there is hope oversight is improved after the restructuring in late 2009 that moved MassHighway and other state transportation agencies under one umbrella, the state’s new Department of Transportation.

It was during the busy time leading up to this major organizational shift that IWR made efforts to get MassHighway’s take on road salting issues. In the community of journalists, the agency is known to be considerably less than accessible, but perhaps because NEIWPCC is not a media organization, it took only moderate persistence to be granted an in-person interview with Henry Barbaro, the Highway Division’s wetlands unit supervisor and one of the architects behind MassHighway’s 2006 Snow and Ice Control Generic Environmental Impact Report or GEIR.

Barbaro works in the agency’s downtown Boston offices, a drab sea of cubicles where decorations were limited largely to a few plaques and a lonely Christmas ornament hanging from a ceiling vent. On the morning of September 28, 2009, the place seemed entirely devoid of energy. Barbaro was anything but. He appeared robust, athletic—and invigorated by his work. For a half-hour, he monopolized the conversation, pontificating about environmental stories he felt the press was overlooking, such as the downside of population growth in both developing and developed nations.

“The unsustainable mining of resources is what is leading to problems,” Barbaro said.

The topic of stormwater came up too, not surprising given the issue’s prominence for any highway agency. When rain falls or snow melts, the ensuing flow of water across land is known as stormwater runoff. And in areas where impervious surfaces prevent percolation into the ground, the stormwater and any pollutants it picks up on its way (including deicing chemicals) flow directly into a water body or into a storm sewer system that discharges into one. Federal water quality regulations require highway agencies to obtain stormwater permits for operations in urban areas.

Barbaro suggested story angles to explore in covering stormwater policy, but understandably steered clear of mentioning his employer’s legal troubles over the issue. The Conservation Law Foundation and other environmental groups sued MassHighway over its approach to stormwater, and in May 2008, a federal court judge responded by ordering the agency to commit to a two-year schedule for adopting a revised stormwater pollution cleanup plan. In December 2009, the Highway Division submitted a revised plan to the court, but the plaintiffs argued the plan is insufficient and should be rejected. The matter remains before the court, with a decision expected in the spring.

As for the Boxford case, if Barbaro had any opinions, he kept them to himself; all employees of both the Highway Division and MassDEP are understandably prohibited from discussing a situation in which their employers are defendants. Barbaro did speak in general about winter road maintenance, and he said sodium chloride, for all its faults, is still the best choice.

“Most alternatives have chlorides in them anyway,” Barbaro said. “There just aren’t good options out there that are as cost-effective and that provide the performance of road salt.”

And the impact on wetlands, his specialty?

“There’s not a discernable impact on them,” he said. “I think what you see being burned up are salt-intolerant street plantings.”

Barbaro was even less effusive on the subject of the 2006 GEIR, in which MassHighway provided a detailed description of its snow and ice control procedures and their impact on environmental resources. In commenting on the report, MassDEP and other environmental organizations criticized a number of practices, none more so than MassHighway’s rate of salt application. The GEIR included a chart based on a 2001 survey, conducted by a consultant, of the snow and ice programs of state transportation agencies in the region. The chart showed MassHighway salting roads at an annual rate of nearly 24 tons per lane mile. (A lane mile is one traffic lane, 12 feet wide, extending for one mile along a road.) According to the chart, MassHighway’s rate was more than five tons above the next highest rate, posted by New Hampshire, and roughly three times the rate in Connecticut.

“That was like comparing apples to oranges to bananas,” Barbaro said, and he had a point. For example, Connecticut at the time used little road salt since it relied primarily on sand as an abrasive to improve traction. In MassHighway’s work plan for its 2012 Snow and Ice Control Environmental Status and Planning Report (ESPR), which the state is now requiring in lieu of the sharply criticized GEIR process, the agency also claimed the numbers in the GEIR chart were skewed by the different ways state agencies track and report salt use. MassHighway said it planned to do a new survey of state salt use that would allow for a more direct, reliable comparison.

The conversation ended with Barbaro’s recommendation that IWR contact other MassHighway officials for their thoughts, and in particular Tom Loughlin, director of statewide operations. It was a good suggestion. While Loughlin requested questions be sent to him in advance, and provided his answers via e-mail, the exchange proved illuminating. In response to a question suggesting that perhaps some of the salt use reflected in the GEIR chart might be explained by MassHighway’s stronger commitment to providing drivers with clear dry roads at all times in winter, Loughlin wrote, “I’m not convinced that MassHighway does use more salt than other New England states. I have no documentation that supports that statement.”

Loughlin wrote that the agency would, as in previous years, be applying salt this winter at a rate of 240 pounds per lane mile. (This is the rate of the salt coming out of a truck’s spreader, not the annual rate cited above.) The Highway Division’s rate puts it within the range of states with a similar climate—New York State’s Department of Transportation, for example, applies at 225 lbs/lane mile—and well below levels seen in some rural, mountainous areas. In the Adirondack Council’s 2009 report Low Sodium Diet, the council said Essex County in Adirondack Park spreads at a rate as high as 1,200 lbs/lane mile. Small wonder birch trees are disappearing.

Loughlin also responded to questions about Massachusetts’s reduced salt zones, which MassHighway established in areas around drinking water supplies and some agricultural lands, such as cranberry bogs. More than 50 such zones exist in the state—the stretch of I-95 in Boxford is one of them—and maintaining them is expensive. In the 2006 GEIR, MassHighway estimated the reduced salt zone program cost $2 million a year in 1995 dollars, primarily due to extra costs for materials. In most of the zones, trucks spray liquid calcium chloride on sodium chloride before it is spread; this practice, known as pre-wetting, helps keep salt from bouncing and scattering once it hits the road. In a zone where the goal is to reduce salt use, pre-wetting is smart strategy. If salt stays in place, less needs to be applied on a second pass.

Extra Attention In Massachusetts, the Highway Division maintains more than 50 zones where salt is applied at a lower rate to minimize the impact of sodium and chloride on water supplies. The list of reduced salt zones includes the stretch of Interstate 95 in Boxford.

Trucks working a reduced salt zone in Massachusetts also pre-treat roads by applying liquid calcium chloride directly to the surface ahead of a storm; this is called anti-icing, and by helping to prevent snow and ice from bonding to pavement, it too means less need for salt. In most reduced salt zones, the Highway Division also mixes road salt with an equal amount of sand, despite research showing salt-sand mixes reduce fewer accidents than straight salt. Think about it: the salt melts the ice, the sand dissolves into the slush, and plows come along and push everything to the side.

So, what good is the sand doing, especially when studies show that even if it stays on the road, sand does little to improve traction at speeds over 30 miles an hour?

“The majority of cities and towns require that we use sand [in reduced salt zones],” Tom Loughlin replied. “They do this as a way to reduce the amount of salt applied. Newer equipment allows us to reduce the application rate, but old habits are hard to break. We would rather use no sand at all.”

It would behoove the cities and towns to heed Loughlin’s desire. Sand has a reputation as a natural way to improve winter driving conditions, and it is even cheaper than salt. But not only is it virtually useless at high speeds, sand is easily blown off roads, and its environmental impact rivals sodium chloride’s: when runoff carries sand into a water body, the sand clouds up the water, and the increased turbidity hurts fish, bottomdwelling invertebrates, and even aquatic plants, which get less sunlight. For a highway agency looking to keep a cap on costs, sand creates another problem. The annual sand cleanup in the spring is a long, costly pain in the neck. For these reasons, sand has largely fallen out of favor as a highway treatment, and even Connecticut’s Department of Transportation, which up until 2006 spread a 7:2 sand/salt mix, has now moved completely away from sand in its winter operations.

In the reduced salt zone in Boxford, the Highway Division avoids sand and instead pre-wets and pretreats with liquid magnesium chloride.

“We have used it to test its effectiveness,” Loughlin wrote, “and we believe it has worked well.”

But magnesium chloride, and liquid calcium chloride as well, can be tricky. Apply them to a road that is warmer than the recommended temperature range for the chemicals, and the surface can get slick, slippery, and unsafe in a hurry.

In an e-mail interview with another Highway Division official, Paul Brown, director of snow and ice operations, he wrote that magnesium chloride and calcium chloride have been used consistently in Massachusetts with no issues. The secret: not overapplying the chemicals and not applying them at the wrong time.

“First, all of our key personnel who are making decisions on applications have pavement temperature sensors,” Brown wrote. “Second, all of the materials spreaders are calibrated and are frequently checked for accuracy . . . Third, our weather forecast is customized for our five districts and 15 sub-districts.”

It sounded impressive, but Boxford’s Rando appeared to be unmoved by the implementation of the reduced salt zone in Boxford or the use of magnesium chloride.

“I don’t know what happens when you mix all the chemicals,” she said.

Hired Hands

If you pressed Rando and the Highway Division’s other critics in Boxford, they might concede one thing: highway agencies have a tough job to do, especially now, with a recession-driven slowdown in tax revenues taking a big bite out of state budgets and the money available for clearing snow and ice. In any industry, a budget pinch can make outsourcing, with its potential to cut costs, look appealing.

Maine’s Department of Transportation has traditionally contracted out just a tiny percentage of its winter maintenance to private companies, preferring to rely almost entirely on state employees and equipment. That is changing.

“We still have a low private contracting percentage for snow and ice control services,” wrote Brian Burne, a MaineDOT highway maintenance engineer, in an email. “However, we have been eliminating numerous positions in recent years, so [contracting] will certainly increase over time.”

Private Matter Independent contractors already do the bulk of snowplowing and salt-spreading on Massachusetts highways, and budget shortfalls are increasing outsourcing’s appeal in other New England states.

But outsourcing, as any student of business will tell you, has its cons, chief among them a loss of control to some degree over operations taken out-of-house. That concern made one disclosure in MassHighway’s 2006 GEIR leap out: the agency predominantly uses privately owned equipment and privately contracted operators in winter. The state provides only 10 percent of the plows and spreaders and loaders, and roughly the same percentage of operators.

This extensive reliance on hired help raises immediate concerns about accountability, supervision, training— and the larger question of whether Massachusetts is sacrificing too much to reduce costs. A conversation with Matt Frazier, president of the Massachusetts Snow and Ice Contractors Association, put some worries to rest.

“There are some snowplow contractors who have been working for MassHighway winter after winter for upwards of 50 years,” Frazier said. “So MassHighway is able to enjoy and reap the benefits of contractors that have been doing this for many, many, many years, and providing the state with equipment that is top-notch. Spreader controls are computerized and automated now; that’s mandatory. And safety is of the utmost concern. We all have safety equipment when we’re loading liquid deicing products.

“To say we’re ill-trained—that’s just totally unfounded. There are training sessions in both the fall and spring, held by MassHighway in all five districts, solely for snow and ice contractors.”

At the training sessions, instructors cover the expected—effective chemical use, the benefits of strategies such as anti-icing, etc. But instructors also remind drivers of their environmental impact and carefully go over the Highway Division’s evolving equipment requirements. For the 2010-2011 winter, for example, all material spreaders must be equipped with liquid prewetting systems. The Highway Division pays a bonus to contractors who install required equipment ahead of deadlines, which helps defray some but not all of the investment.

“It costs about $4,000 for a set of plastic tanks [for liquids] and a separate control station for the cab,” Frazier said.

That is a major expenditure in a business where fickle weather plays a powerful role.

“The winter before last,” Frazier said, “I had a truck that had 19 hours on it all season long. That’s a big investment to have just sitting there. Some of the hired plows that winter got out only four hours.”

For a contractor, a tame winter is bad for the bottom line. Not so for the state, which pays private plowers and spreaders only for the time they are working.

“Every taxpayer reaps the benefits,” Frazier said. “There’s no retirement system. There’s no paid sick time. There’s no paid vacation time. We are on call, 24 hours a day, seven days a week, from November 15 to April 15, with no compensation unless the wheels turn on our trucks.”

Environmental Examination

Listening to Frazier, who spoke with a disarming candor and gruffness, it was hard not to feel Massachusetts roads and its drivers are in good hands when the snow starts flying. In some respects too, the accusation that MassHighway was some kind of renegade outfit, beholden-to-nobody, did not ring true. For one thing, the very system of checks and balances that in theory keeps the three branches of government in line in Washington also applies to state government. While it may seem counterintuitive to imagine one state agency taking a tough, even combative stance with a fellow state division, it does happen.

In an interview with Iris Davis, who works in risk reduction and enforcement at the Massachusetts Department of Environmental Protection, she disputed the notion that the environmental agency avoids going after the Highway Division.

“That’s not true,” Davis said. “We’ve fined them for doing things.”

And criticized them. MassDEP’s comments on MassHighway’s 2006 GEIR were incisive. In one comment, the agency questioned MassHighway’s claim of a weak correlation between sodium levels and distance from a highway; MassDEP said additional analysis was needed. This pointed prodding of MassHighway might lead you to think MassDEP could have been a big help to the residents in Boxford. But the primary drinking water concern of any state’s environmental apparatus is in protecting public supplies, not the private kind.

“We have no authority over private wells,” said Kathy Romero, a regional planner with MassDEP’s drinking water program. “We do offer assistance when someone calls in and says ‘I think there’s a problem,’ but mostly we tell them what they should test for, and refer them to certified laboratories.

”State departments of public health can also be a resource for well owners who suspect contamination, but for the most part, wells are a local issue.

“In Massachusetts, the state drinking water regulations give municipalities the authority to implement land-use controls through local by-laws,” Romero said. “And that’s the case around drinking water supplies.”

The trouble is most local health officials have day jobs too. They may lack time and expertise to adequately deal with well issues; motivation can be lacking too if, when compared to other pressing health matters, the threat to wells seems minor.

In Boxford, the Board of Health took heat over the years from residents in the salt-affected corridor who found the board’s response lacking—but the law-suit has helped change that view somewhat. And as it turns out, the town is not entirely on its own in this matter. Another player recently got involved, one that wields undeniable power—the U.S. Environmental Protection Agency.

“The town contacted us and asked for advice on what to do,” said Doug Heath, a hydrologist at EPA’s New England office for 25 years. “So we went out and took a number of readings, and got to know the area better.”

What the EPA team discovered on its visit to Boxford in February 2009 was enough to convince the agency that MassHighway’s salt storage shed might be in violation of the Clean Water Act. In September 2009, EPA sent a letter to MassHighway requesting information to determine if a violation had indeed occurred. EPA expressed concern about runoff from the paved area surrounding the shed and also singled out the scavenger wells, which EPA wrote had been “reportedly” used by MassHighway to discharge untreated groundwater to nearby surface waters without the required federal permit.

Section 308 of the Clean Water Act authorizes EPA to make such a request for information; the section also requires the recipient to respond. On January 4, 2010, the Highway Division submitted its response, a nearly one-inch stack of documents replete with maps, sampling data, and detailed responses to EPA’s questions. Through a Freedom of Information Act request, IWR received a copy of EPA’s letter and the Highway Division’s voluminous reply. To meet the deadline for publishing this article, only a limited examination of the copious information could be performed—but even this yielded insights.

MassHighway’s sampling in 2006 and 2007 showed very high sodium and chloride concentrations in streams just off I-95, followed by much lower concentrations in the tributaries into which the streams fed. Data from more recent sampling show high sodium and chloride in brooks adjacent to the salt shed, and rapid dilution as the water moves away. As for scavenger wells, a map shows two of them, on either side of I-95. Sampling of water pulled up by the well on the west side, near Rando’s home, shows sodium at 314 mg/L and chloride at 607 mg/L in March 2006; those high levels taper off but remain elevated on May 2007, the last date for which data are provided. On the matter of whether a federal permit may have been needed for any MassHighway activities in Boxford, the Highway Division rejected the idea with a blunt explanation: “The Boxford salt shed is not located in the watershed of a public drinking water supply.”

Neil Handler, senior enforcement coordinator with EPA New England’s drinking water program, said the response is being “evaluated.” In the meantime, in Boxford, the wait for a resolution continues, with some residents beginning to think the potential effect of sodium on their health is less likely to inspire a solution than concerns about chloride’s impact on aquatic life.

“I think that’s what gets more attention than the human factor,” Rando said. “It’s truly sad because we can suffer, but the people who react first are the ones who care about some type of funky bug getting killed.”

Rando’s resentment was a bit misplaced, since the interconnectedness of an ecosystem means what happens to funky bugs ultimately affects all living things in an environment, including humans. Chloride concentrations matter to people and to water bodies. And in recent years, the work on chloride has gone beyond research to active efforts to reduce chloride’s presence through a plan known as a Total Maximum Daily Load or TMDL. The Clean Water Act requires that states develop TMDLs, which specify the maximum amount of a pollutant a water body can receive and still meet its water quality standards, for all impaired waters. The first step in this process therefore is to identify a water body as impaired for a contaminant—chloride, in this case. That is just a matter of looking in the right place, according to Susy King, a NEIWPCC environmental analyst and coordinator of our TMDL Workgroup.

“Some states may not have many waters listed with chloride impairments, but this isn’t necessarily because the problem doesn’t exist, but rather the fact that the impairments haven’t yet been identified,” King said. “The experience in New Hampshire shows that if you look for chloride impairments, you will find them.”

Plan For Action

What started New Hampshire on the road toward extensive chloride research and ultimately a chloride TMDL was not concern about funky bugs but rather traffic jams. The stretch of Interstate 93 between Salem and Manchester is notoriously congested, so to free up the gridlock, the state announced plans to widen the highway by two lanes in either direction. That triggered the need for an Environmental Impact Statement or EIS. In September 2002, New Hampshire’s Department of Transportation released a draft EIS claiming the highway expansion would have no clear impact on streams, wetlands, or drinking water resources along the I-93 corridor. One scientist who did not buy that assertion was EPA’s Doug Heath, the same Doug Heath who did the testing in Boxford.

Rebuilding I-93 New Hampshire’s push to widen the congested highway between Salem and Manchester led to a closer look at the impact of road salt on watersheds in the area.

“[NH DOT] argued that chloride levels before construction in one of the streams, Policy Brook in Salem, would not exceed I think about 6 ½ mg/L of chloride, and I thought that was rather low,” Heath said. “There was no data to back that up. They also made the claim that even with the addition of extra lanes that the concentration would not exceed about 13 mg/L. I knew from past experience doing a lot of measurements around New England that we rarely found levels that low except in pristine headwater areas far from any road networks. So I challenged their claims.”

Heath’s challenge led to a meeting between EPA and NH DOT, and ultimately an agreement between the two parties and New Hampshire’s Department of Environmental Services to jointly collect water quality samples in several streams near the highway. Heath pulled on his waders and went to work.

“I was out there about five winters,” Heath said, “tramping through deep snow, breaking through ice, retrieving data loggers that take readings every 15 minutes of specific conductance [a surrogate for chloride] and temperature.”

By the time Heath stopped monitoring, he had data showing numerous cases where chloride exceeded the chronic and acute criteria identified by EPA in 1988 and adopted by New Hampshire. The evidence put the TMDL process into motion. In 2006, NH DES listed four streams—Beaver Brook, Dinsmore Brook, the northern tributary to Canobie Lake, and Porcupine- Policy Brook—as impaired for chloride. That sparked even more intensive water quality monitoring as NH DES worked to develop TMDLs for each of the streams and their watersheds. To keep the process inclusive and get input from all corners, the state created a salt reduction workgroup, which periodically brought together federal and state environmental and transportation staff (including EPA’s Heath), municipal public works officials, and environmental experts from academia.

The work proceeded collaboratively and rapidly, in part because New Hampshire had a model to follow; while the state was the first in New England to work on a chloride TMDL, Minnesota had already developed one for a watershed in Minneapolis. In 2008, NH DES completed the four TMDLs and submitted them to EPA, which granted its approval in January 2009. But the work has not stopped there. With the TMDLs in hand, now has come the hard part—implementation.

Although each TMDL differed slightly in its findings, one conclusion was consistent: road salt is contributing the bulk of the chloride, as much as 98 percent in two of the streams. To get the chloride down to the allowable level established in the TMDLs, each of the sources of road salt in the streams is going to have to cut back.

“It’s a question now of how do we split up the [chloride] budget,” said Steve Silva, chief of EPA New England’s water quality branch. “How do we split up the loads, and how do we work together—all the chloride users in the watershed—to come up with approaches that will provide for public safety but limit the adverse impact on the environment.”

Close Contact One of four streams in New Hampshire found to be impaired for chloride, Beaver Brook passes directly under Interstate 93 not far from NH DOT’s Patrol Shed 528.

In the TMDL studies, NH DES suggested that to bring down chloride levels, annual use of road salt on each of the major sources—parking lots, state roads, municipal roads, and private roads—should be reduced by an equal percentage. NH DOT has a different take. In May 2009, the transportation department published its implementation plan for meeting the chloride TMDLs, and made clear that in its view the heavier traffic volume on state roads—and hence the less salt being used per vehicle—needs to be considered. To not do so, NH DOT argued, would be to reward municipal and private salt spreaders that have been “less efficient or prudent” with road salt use than the state. The transportation department proposed a different vehicle-based allocation in which NH DOT would be allowed to use considerably more road salt than NH DES suggested.

Reading NH DOT’s plan, it sounded like the stage was set for intrastate warfare. Not so, said NH DES’s Eric Williams, a member of NEIWPCC’s Nonpoint Source Pollution Workgroup and a key member of the team working on implementing the TMDLs.

“I didn’t see anyone jumping up and down, saying ‘Gee, DOT, the vehicle-based allocation is a great idea,’” Williams said. “At the same time, I didn’t see municipalities saying ‘No way, we’re not going to allow them to do that.’ The TMDL documents say [NH DES’s suggested allocation] is a starting point for the salt reduction workgroup to use to develop final sector allocations.

“One of the things we would like to see is if one sector is proposing to use more than their suggested share of road salt, then we would like to see them take a leadership role in working with the other sectors to make additional reductions happen. We’ve laid that out to DOT, but I don’t know if they’re willing to do that.”

However the allocation debate is resolved, one thing is clear: significant reductions in salt use by private contractors must be achieved to meet the TMDLs’ chloride targets, and that will not be easy. Unlike in Massachusetts, where private appliers can be contacted through Matt Frazier’s contractors association, the drivers who use their own equipment to plow and salt private roads and parking lots in New Hampshire are not accessible through an organized body.

“We don’t even know who they are,” said Barbara McMillan, NH DES’s watershed outreach coordinator.

That means NH DES may be doing some very personal outreach.

“In Derry, they said if you stood at the transfer station in the summer as landscaping trucks brought their brush for disposal, and looked at which ones had plow rigs on the front, you probably could make a pretty good list of who’s doing [winter road] work in Derry,” Williams said. “We realize we have to do things like that.”

Locating contractors is just the first challenge. An even tougher task will be convincing them to use less salt. In a report published in 2006 by the city of Madison, Wisconsin, the authors reported private trucks were pouring sodium chloride onto parking lots at well over twice the rate of application used on the city’s streets. Other studies report similar findings—and there is no mystery why. When a driver signs a contract to salt a parking lot, he or she assumes liability for anything that might happen—an accident or even a fall—if the lot is not deiced to a level of safety. Highway agencies face liability as well, as seen by lawsuits they periodically face from families who blame a loved one’s death on a failure to clear snow and ice. But for contractors, operating as they do with a slim profit margin under constant assault from rising fuel and insurance costs, the need to avoid liability for an accident is acute. The solution: hit parking lots with salt, and hit them hard.

In New Hampshire, efforts are underway to reduce this temptation. Legislation has been introduced that would provide limited liability relief for private salt spreaders as long as they are following recommended treatment guidelines; the bill also calls for establishing a training and certification program for road salt applicators. If the program is adopted, it could have a major impact, judging by the experience in Minnesota. Through a grant from that state’s pollution control agency, a consultant developed and conducted training programs for contractors on best management practices for applying road salt. At the end of each program, all qualified attendees received a certificate documenting their knowledge of BMPs and commitment to implementing them. The pollution control agency called the results “astounding,” citing the case of a shopping center parking lot where the training led to a reduction in salt use of 80 percent.

But for now, a training and certification program in New Hampshire is nothing more than a possibility. On the other hand, achieving the goals set in the TMDL is imperative. Well, almost. A provision in the Clean Water Act allows states to not meet the standards in a TMDL, but it is rarely invoked. A state would have to go through the onerous process of proving that any one of six factors, including substantial and widespread economic impact, overrides the need to meet the TMDL targets. Not only is the process complex and time-consuming, it is also a politically perilous and unpopular path to take in environmentally conscious New England. So the pressure is on.

“Getting agreement on the allocations of road salt is probably the biggest hurdle at this point,” Williams said. “If we don’t get anywhere, I think the default is [NH DES’s suggested allocation] in the TMDL. If that’s the case, and DOT doesn’t meet the TMDL, they can’t build and operate a fourth new lane on either side of the highway, according to their permit documents. We think that’s a pretty urgent concern.”

German Engineering The high-end equipment in use at New Hampshire’s Patrol Shed 528 includes several material spreaders made by Schmidt, a German manufacturer. The Stratos model is said to provide extremely precise dosage and distribution.

In its implementation plan, NH DOT pointed out that it has already implemented a costly series of best management practices at Patrol Shed 528, which is in the TMDL watershed of Beaver Brook. During IWR’s visit to the shed, supervisor Frank Qualey pointed out evidence of the BMPs and progressive equipment in place at 528—the expensive Schmidt spreaders from Germany said to generate better road conditions than traditional spreaders and do so with less salt; the roughhewn shed where crews generate their own liquid brine for pre-wetting and anti-icing; the three trucks with underbelly plows, which are extremely effective at scraping snow off a road, meaning less salt needs to be applied. Incorporating these measures into the other five sheds in the TMDL watersheds would cost $6 million, according to NH DOT, and even then, the department said the result would be no more than a 20 percent reduction in salt use.

There is another tantalizing option—a full conversion to using a non-chloride based deicing alternative. In its plan, NH DOT wrote that a switch would reduce salt use by as much as 63 percent—impressive but impractical, in the transportation department’s view. Given what we have learned over the years about alternatives to sodium chloride, most winter road maintenance experts would probably agree with DOT’s assessment.

Weighing The Alternatives

In a 1992 study that is widely cited even today, Donald Vitaliano, a professor of economics at Rensselaer Polytechnic Institute in Troy, N.Y., examined whether it would be “socially efficient” for highway agencies to switch from using road salt to an expensive but more environmentally benign, far less rust-inducing alternative, calcium magnesium acetate or CMA. Vitaliano took into account all of salt’s known side effects—chloride’s costly corrosion of reinforcing steel in bridges, the rust on cars and trucks, the damage to trees—and befitting an economist, he quantified everything by ascribing to each factor a dollar amount. That was relatively simple in the case of bridge corrosion, since alarming estimates of the insidious damage wrought by chloride on the nation’s transportation infrastructure were already being widely circulated at the time. Vitaliano worked harder to put a number on the aesthetic damage caused by salt’s effect on trees, but through a largely inscrutable method of calculation, he came up with a social cost of $75 per ton in environmentally sensitive areas. In the end, Vitaliano concluded a switch to CMA made sense, because while its selling price was some $600 per ton higher than sodium chloride’s, the other costs associated with salt use drove its actual price above CMA’s.

Vitaliano’s report came out just a year after an even more highly publicized study comparing salt and CMA by the federal Transportation Research Board. That study reached the opposite conclusion—that a wholesale switch to CMA was unwarranted, primarily because of its high cost. Who was right? Judging by the failure of CMA to make much of a penetration into the market for deicers, the TRB appears to have made the right call. More likely, Vitaliano’s assessment never had a chance. The upfront cost of CMA was and still is just too high for most public and private deicing operations, regardless of the savings its use might reap in the long run.

Still, almost 20 years after the TRB report, makers of CMA and other non-chloride based deicers have not given up the fight. Sometimes they sound an awful lot like Vitaliano.

“What we’re unable to do in our society is look at the lifecycle cost,” said Keith Johnson, president and CEO of Cryotech, a leading maker of CMA and other alternative deicers. “If you’re putting salt on a bridge, and you have to replace the bridge deck every 15 or 20 years because of chloride, you know, the price difference between salt and CMA is not quite so much. As a matter of fact, I think you would find out it’s probably your best economic choice to not put any chlorides on a structure at all.”

That argument still has resonance. Johnson said Cryotech is doing big business with airports where the additional investment for a less corrosive alternative to salt can easily be justified; nobody likes a corroded airplane. And there remain isolated instances where road authorities are willing to spend extra money to use something other than salt. The city of Olympia, Washington, used CMA exclusively and happily for years (though Olympia did switch this winter to a cheaper organic liquid brine that includes molasses). And on one of New England’s most heavily traveled bridges, the span of Interstate 89 that crosses over the Connecticut River between New Hampshire and Vermont, much of the clearing of ice and snow on the southbound span has been done in recent years by a fixed automated spray technology or FAST system, which squirts a sister chemical to CMA, potassium acetate, through 60 nozzles built into the bridge deck. Sensors in the deck automatically trigger the spraying if conditions warrant.

Bridge Work A system installed on the southbound span of the I-89 bridge between New Hampshire and Vermont automatically sprays the deicer potassium acetate through nozzles in the pavement. Maintenance and repairs are done at night to minimize traffic impacts on the busy bridge. Photos courtesy of New Hampshire Department of Transportation

Vermont and New Hampshire put in the FAST system to see if the results would justify installations elsewhere. Alan Hanscom, who oversees the system as NH DOT’s district engineer for the area, did not sound awed.

“It certainly sprays at least as much as we think is necessary and then some,” Hanscom said in early January. “It’s really most helpful when nobody is out and around. If there are freezing fog conditions at 2:00 in the morning and nobody knows about it and the deck freezes over, this would address that, whereas we would have to wait for someone to call us after a crash.”

Hanscom said the system was down for maintenance, and he did not sound like he missed it—or the potassium acetate.

“For the cost, it certainly didn’t work 30 times better than salt,” he said. “The freeze point is so low, in the minus-70°F degrees range, that there’s always some residue out there. In a cold storm where the snow normally blows right off, the snow instead sticks to the deck, then the snow wets up and more snow gathers, it gets slippery, the system sprays, and the cycle continues. It creates its own problems sometimes.”

Despite being biodegradable, acetate-based deicers are not completely harmless in the environment either. Research shows acetates can cause an increase in biochemical oxygen demand or BOD in receiving waters, creating an environment with less of the oxygen that fish and other aquatic life need to survive. BOD issues are also a problem for benign-sounding organic deicers such as GeoMelt, which are based on agricultural byproducts from the processing of sugar beets or corn.

Even ever-natural urea—yes, the very substance found in the urine of all of us mammals (though it is synthetically produced for use in industry)—poses environmental concerns. Urea effectively melts snow and ice, and is minimally corrosive. But it is high in nitrogen, which can be carried by runoff into waterways and cause dangerous algal blooms. Urea has been the deicer of choice at many airports, but in August 2009, EPA announced plans to restrict its use on runways.

The other deicers in the chloride family have their faults as well, in addition to being more expensive than sodium chloride, a bargain by comparison. A survey of U.S. and Canadian transportation officials conducted in 2007 for the National Cooperative Highway Research Program found magnesium chloride, which is being used in Boxford, to be the second most popular snow and ice control chemical after common road salt. That is understandable; magnesium chloride dissolves more easily and acts more quickly than sodium chloride, and is less toxic to plants. But it is highly corrosive, a knock against it that calcium chloride and potassium chloride share. Furthermore, all three chloride alternatives typically are applied as liquids, and the costly equipment upgrades necessary to move into liquid treatments can be an unwelcome stretch on a budget.

The one problem every alternative shares—chloride-based or otherwise—is their relatively short history of use, which cloaks our awareness of potential longterm adverse effects. Stories like the one that came out of Colorado illustrate the legitimacy of this concern. Three electric cooperatives reported an increase in outages and pole-top fires, which they blamed on liquid magnesium chloride being applied on roads in the area. As the coops described it, traffic was churning the magnesium chloride into a mist that rose and coated insulators on utility poles, leading to hazardous electric arcing.

“Introduction of any agent must be done with caution due to unintended consequences within complex systems,” wrote Lori Siegel, an environmental engineering consultant and writer of a report on road salt’s impacts used in New Hampshire’s TMDL development process, in an e-mail interview. To some, the more you look at the alternatives, the better good old-fashioned salt looks.

“There are no real cost-effective alternatives to sodium chloride,” wrote Paul Brown of the Massachusetts Highway Division. “The alternative chemicals are used to enhance the salt, not replace.”

Less Brawn, More Brains

According to the Salt Institute, the key to achieving safe roads with minimal side effects can be summed up in two words—sensible salting. That is the name for the program the institute initiated in 1992, and through which it claims to have trained more than 100,000 American and Canadian snowfighters. Sensible salting emphasizes properly covering salt supplies, correctly maintaining all equipment, calibrating spreaders accurately, applying salt appropriately, and being concerned about the environment as well as public safety. All that does make sense, except it is being promoted by an organization representing salt producers, who you think would prefer their trade group push practices that result in more salt used, not less.

“Sensible salting in a sense is out of our favor,” the Salt Institute’s Mort Satin said. “But the industry is in this thing for the long run. They don’t want to be labeled as bad guys. They feel there’s nothing else they can do except minimize the impact, because if they don’t, the negative environmental effects are going to hasten the demise of the use of salt on roads.”

Satin said the institute had just finished a large study with the University of Waterloo in Canada that verified with hard data the benefits of sensible salting. Although Satin sounded trustworthy, a call was placed to the University of Waterloo’s Mike Stone, who headed up the study. Stone confirmed Satin’s analysis.

“We drilled a number of holes and looked at groundwater concentrations and chloride loadings in soils adjacent to various road types,” Stone said, “and what we found was that if you reduce the loading by 25 to 40 percent in salt vulnerable areas, you’ll get a 25 to 40 percent reduction in chloride transfer in the adjacent soils and therefore into the water table. This is one clear example of how the impact of road salt can be mitigated to a certain extent.”

While road salt may be old school, techniques for reducing its use now include technological innovations of impressive range. Many of the new systems are being evaluated through Clear Roads, a research project supported by funds pooled from state highway agencies. Paul Brown of the Massachusetts Highway Division serves as chair of Clear Roads’ technical advisory committee, and even in an e-mail interview, his enthusiasm for the work came through.

Responding to a question about research into snowplows with multiple blades, Brown wrote, “The concept is radical and a significant move into the future. This is a huge undertaking for any agency, and people do not immediately embrace change. It will take some time for agencies to embrace but once people see the cost savings it will be apparent that [the multi-blade concept] should be part of a snowfighter’s tool box.”

Clear Roads is also looking closely at zero-velocity spreaders, which release salt at the same speed but in the opposite direction that a truck is traveling. With the two speeds cancelling each other out, the effect is like a stationary truck placing the salt on the road—no bounce, no scatter.

“The research will go a long way toward establishing the value this type of spreader has in a fleet,” Brown wrote. “I am sorry to say [the Highway Division doesn’t] have any zero velocity spreaders. I wish we did. They may be the most effective tool for applying deicing materials to high speed roads.”

Not all technology employed in the field is new and hot out of the testing facility. Road weather information systems have been around for more than two decades, but they remain a tremendous asset. In an RWIS, a weather station set next to the highway works in conjunction with a pavement sensor to provide real-time, location-specific information about conditions in the air and on the ground, allowing transportation officials to make smart decisions about when and where to apply salt. Many states rely on them extensively, including Maine, which now has nine RWIS sites. According to MaineDOT’s Brian Burne, the state spent $270,000 installing the systems and is spending $14,000 annually to calibrate and maintain them.

Roadside Assistance Small, unmanned weather stations are increasingly popping up on the sides of highways as transportation agencies invest further in road weather information systems or RWIS. Data from the stations and associated pavement sensors help determine how and when to treat specific sections of road. Photo courtesy of Adirondack Council

“We have found them to be a good tool,” Burne wrote, “especially for remote or problematic locations.”

States now are also routinely doing pre-wetting and anti-icing, although a recent incident in Vermont points to the potential for newer snow and ice practices to be misinterpreted by a public accustomed to traditional road salt use. On January 4, 2010, Vermont experienced a storm that turned into a nightmare for crews trying to clear the roads. First it snowed, then it rained, then more snow fell, heavier and harder. In the evening, temperatures plunged to the low single digits and stayed there for two days.

“Think of it as a baseball game with Mother Nature pitching,” wrote Gil Newbury, a district administrator with Vermont’s Agency of Transportation, in an e-mail. “The roads are wet and all the salt is washed off—strike one. Dump lots of wet, heavy snow on the road right at commuting time and let the traffic pack it onto the road until it turns to ice—strike two. Then drop the temperatures so low that salt and salt brine do not work—strike three.”

The brine VTrans used in some areas during the storm was a blend of salt and water, mixed with a small amount of Ice-B-Gone, a popular liquid magnesium chloride product. The brine has an oatmeal consistency, which helps it stick to roads. But to drivers, it looks different. And when multiple cars began sliding off roads, particularly on one stretch of road where brine had been applied extensively, fingers were pointed—at the brine and at VTrans. A rumor went around that the brine had been mixed incorrectly, leading to the driving conditions. Newbury denied a bad mix was the problem.

“The brine sure didn’t cause the problem,” Newbury wrote, “but we were a little short on being able to fix the problem as quickly with the brine as we would have liked. That’s an infrastructure challenge we are working to correct as I write.

“The bottom line is that there are times where Mother Nature is going to win despite all efforts, technology and expectations. The best hitters in baseball fail 70 percent of the time, and so will we at times. None of us were happy about that particular storm, but we did learn some good lessons and are already correcting our weaknesses for the next time.”

Behavior Matters

With all the talk about new technologies and treatments, it is easy to overlook what would be the least expensive, most effective way to improve safety on winter roads while reducing impacts from chemical applications—slow down. States have undertaken outreach campaigns to get this message out, but the message gets mixed when drivers see multiple salt-spreading trucks teaming up in a choreographed attack on a highway.

“If you’re maintaining the roads for high-speed traffic,” NH DES’s Williams said, “and at the same time asking people to drive slower, it doesn’t add up.”

To send a coordinated message, therefore, would require that highway agencies ease off on the deicing pedal, no easy feat.

“As little as 50 years ago, deicing materials weren’t used, and when it snowed people expected to drive in snowy conditions on snow-packed roads,” VTrans’s John Narowski said. “Obviously things have changed over the years, and our culture’s expectations are a lot more demanding. That’s a hard one to counter.”

Those expectations are everywhere, even in Canada, where the nation’s environmental agency has taken a highly publicized stance, labeling chloride salts as toxic and warning of their effect on the environment and biological diversity. At the request of Ontario’s environmental ministry, the University of Waterloo’s Mike Stone evaluated the effectiveness of Canada’s voluntary road salt management programs. He discovered during a workshop with winter maintenance managers that the push to cut back on salt was being imperiled by driver demands.

“People expect in the middle of February to get in their car, jump on the 401, the major highway here, and drive to Toronto at 120, 150 kilometers an hour [75, 93 mph], even if it’s snowing and they’re in a blizzard,” Stone said. “So people are putting a lot of pressure on the road authorities. In the workshop, they were saying, ‘Well, wait a minute, we don’t want to be liable, and we don’t want to have people phoning us all the time, so we put more salt on than is appropriate.’ So not only do we have to train private contractors, and continue to train and upgrade municipal individuals and provide them with better technology, we need to educate the public so they better understand the demands placed on road authorities and the potential implications of road salting.”

The Dry Look Expectations from today’s drivers for clear roads in even the worst winter weather put pressure on road authorities to treat roads to a degree beyond what is necessary for basic safe travel. Measures such as mandatory snow tires and lower speed limits in bad weather would reduce the need for treatment, but are difficult to impose.

During the salt reduction workgroup meetings in New Hampshire leading up to the development of the TMDLs, participants discussed a wide range of ways to use less road salt and achieve chloride reductions, including lower speed limits during storms, a greater willingness from school districts to declare snow days, and even passing a law requiring all drivers to take a winter weather driving course. All interesting ideas, but they never made it beyond the discussion stage. The idea of making snow tires mandatory also came up, and were that to happen, New Hampshire would not be the first. In Quebec, snow tires already are required, as they are in Sweden. The problem with a snow tire rule is the same as with a requirement telling everyone to stay home when it snows. Just as not everybody can telecommute, not everyone can afford a new set of snow tires.

Considering 75 percent of Americans drive to work, and most expect to drive fast regardless of conditions, it is hard to imagine environmental arguments about the risks of road salt having much impact on driver behavior. But drivers may be more open to the green pitch than expected. During the New Hampshire TMDL process, Plymouth State University conducted focus group discussions with drivers in Windham and Concord; the university reported the single most dominant message emerging from the focus group talks was that the driving public is willing to receive information from the state regarding the environmental impacts of road salt, and using that information, may be willing to change driving habits.

The Cary Institute’s Gene Likens also found evidence that environmental messages carry surprising weight during his studies at Mirror Lake. When a small road serving a housing development near the lake was paved in 2005, Likens anticipated an increase in sand and salt application. Figuring it was worth a shot, Likens talked to the road manager about the impacts of salt inputs to the lake. If the manager had been planning to use more salt and sand, the talk with Likens changed his mind. The anticipated increases never happened.

“I think we definitely underestimate the potential to respond to environmental messages,” Likens said. “Communication can go a long way, you know. Rather than yelling at somebody, talk to them.”

Looking Ahead

To outside observers of the work on winter road maintenance in recent years, it can appear that despite all the effort, we are no closer to a solution that satisfies all parties than we ever were. But appearances can be deceiving. Progress is happening. It is just not happening all at once, nor necessarily should it be.

“The knee-jerk reaction on a lot of this stuff is to say the problem is too big, it’s too expensive, we don’t know how to tackle it, so let’s do nothing,” EPA’s Silva said. “We’ve seen a lot of things come down the road in environmental protection over the last 35 years since the Clean Water Act was passed that all looked impossible at the outset. Then we’ve figured out how to address them by phasing things in, doing one piece of the pie at a time.”

The lessons learned from the TMDL process in New Hampshire are already proving to be helpful to other states as they move toward possibly developing their own chloride TMDLs. In Massachusetts, EPA’s Doug Heath is out in the field again, sampling for salt impacts to six streams and two water supplies in the area of proposed lane additions to Interstate 93. In Vermont, transportation officials are awaiting a final draft of a U.S. Geological Survey salt impact study triggered by plans to finally complete the Chittenden County Circumferential Highway. And in Connecticut, where a major expansion of Interstate 95 has been proposed, USGS is monitoring four stream locations for sodium and chloride counts to establish a baseline for comparison to the loads expected from the widened highway.

Head to Pelham, N.H., and you find another example of promising activity. This past December, the town became home to New Hampshire’s first porous asphalt road, thanks to a partnership of the University of New Hampshire Stormwater Center, developers, contractors, and Pelham officials. Porous asphalt, which lets stormwater drain through the road rather than pooling on the surface, now covers 900 feet of a road as well as driveways and sidewalks in a new Pelham condominium complex. Research at the UNH Stormwater Center has shown the permeability of porous pavements means 75 percent less salt than normal needs to be applied to a snowy surface to provide the grip drivers need. The porous structure provides a different route for sodium and chloride to pass through to groundwater, so such installations are unlikely near water supply wells. And widespread adoption on highways is doubtful given the expense of replacing existing surfaces. But on parking lots, where so much sodium chloride is applied, porous pavements provide one way to cut back on salt use. That is the kind of progress the stormwater center has been advocating for years.

Easy on the Salt An adult community in Pelham, N.H., now boasts the state’s first porous asphalt road. Research conducted by the University of New Hampshire Stormwater Center shows porous pavements require less salt for winter deicing than do typical road surfaces. Photo by Robert Roseen, UNH Stormwater Center

“We’re not saying ‘no more development’,” said Tom Ballestero, the UNH Stormwater Center’s principal investigator and lead scientist, and a NEIWPCC Commissioner. “What we’re saying is that it would be nice if we could make whatever we do be hydrologically transparent. That is, the water we send to our receiving streams is no different, in quantity and quality, than if we had never done development. That’s the Holy Grail. That’s what we are after. One way of achieving that with salt is by trying to use less of it.”

Whether all the focus on ways to use less road salt and minimize its impact on the environment is part of a trend that will end in the abandonment of sodium chloride as a deicer is remote. Among practitioners of winter road maintenance, salt remains the treatment of choice by a wide margin, and the factors that propelled it to that position remain in place. For more than 60 years, road salt has been poured on snowy roads and parking lots. Will it still be in use 60 years from now? On that question, Massachusetts Highway Division’s Tom Loughlin felt no need to elaborate.

“Yes,” was Loughlin’s unvarnished reply.

Except for those well outside the current of the environmental mainstream, nobody is really pushing for a total termination of salt use anyway. Not even the folks in Boxford.

“I don’t want to get into an argument with people about whether public safety on the highway is more important than drinking water,” Eisenberg said. “That is a no-win argument. What I say is leave the salt barn there, and put in a public water supply for the houses that are adjacent to the highway, and we can coexist together.”

The edge in Eisenberg’s voice ebbed slightly before he spoke again.

“But you know,” he said, “these are not easy issues both for the town or the state.”

Few would dispute him on that point.