The Salty Truth: Revealing The Need For Stricter Road Salt Application And Storage Regulations In The United States
The following Comment was written by Sara Labashosky and you can find a copy of it by clicking here.
Each year during the winter months, salt trucks apply billions of pounds of road salt to icy roads across the United States. For individuals traveling on these roads, road salt is a life-saving, road clearing device that allows for a safer commute. With the wide spread use and perceived necessity of road salt, it is easy to overlook the many negative impacts this chemical compound has on the environment, especially the nation’s water systems. Recent research has revealed just how damaging the use of high quantities of road salt truly is.
Although many view road salt as the most “economical and effective” way to deice roads during the winter, the detrimental re- sults of its use are beginning to appear. Most notably, road salt directly affects the toxicity of rivers and streams as well as the quality of human health, wildlife, soil and vegetation, and infrastructures across the nation. Currently, “[s]even out of [twenty] U.S. rivers- four in Wisconsin, one in Ohio and two in Illinois- have average chloride levels that approach or exceed the Environmental Protection Agency’s (EPA’s) guideline for protecting aquatic life.”
These high chloride levels may cause many water species vulnerable to chloride to become extinct in the near future.
The reason for these extensive consequences is that road salt does not disappear after its application; rather, it remains in rivers and groundwater for years. Because of this characteristic, citizens should be concerned with the continued use of high levels of road salt each year. Researchers have already reported significant negative impacts relating to the use of road salt across the nation, and the repeated annual use of billions of pounds of road salt will only make the situation worse.
Some states have begun to recognize a number of alternatives to using high levels of road salt. Many of these techniques, how- ever, are only in their beginning stages of development, and several of them may prove to be very costly. Still, some communities remain determined to find an appropriate solution to this growing environmental problem. Individuals can also help combat this problem by taking their own small steps toward reducing the damaging effects of road salt.
Section II of this Comment first describes the chemical composition of road salt and why it is so damaging to the environment. Next, Section III explains the country’s current regulatory system (or lack thereof) regarding deicing chemicals. Then, Section IV discusses the pros and cons of new techniques and alternatives to the use of road salt. Further, Section V examines whether road salt can ever cease to exist as a deicing product and discusses what the best approach to the problem may be. Finally, Section VI discusses how lawmakers and state transportation officials should proceed in the future and analyzes potential problems facing those individuals looking to better regulate road salt use.
II. BACKGROUND A. Use and Origin of Road Salt
More than seventy percent of the United States’ roadways are located in “snowy” regions receiving more than an average of five inches of snow per year. Almost seventy percent of the United States’ population lives in these regions. Every year, more than 1,300 people are killed and over 116,800 are injured in automobile collisions on snow-covered or icy roadways. Researchers believe the use of road salt decreases the cost of accidents caused by snow or ice by eighty-eight percent. Maintenance of snowy and icy roads during the winter months makes up approximately twenty percent of state Department of Transportation maintenance funds.
In 1940, Detroit was the first city in the world to use salt to deice its roads. Since then, the amount of road salt used annually has steadily increased, with now over twenty-two million tons of road salt used across the United States every year. Road salt sales represent sixty-five percent of salt sold in the United States, accounting for a national industry worth nearly two billion dollars.
Public works departments across the country usually start the winter season with approximately twenty-five percent more road salt than they estimate they will require for the season. The salt for roads comes from mines located in various regions around the world. In the United States, salt mines exist under Detroit, near Cleveland, and in New York, Louisiana, and Kansas.
Salt is mined “dry” from “underground seams of crystal salt, which formed from the evaporation of ancient seas.” Once mined, the salt is transported to a factory where workers combine it with other chemicals and place it into bags for sale. Trucks then deliver the bags to various retail and hardware stores. If the salt is intended for bulk sale, factories typically store it under tarps or in storage facilities.
Road Salt’s Chemical Composition
The chemical name for road salt is sodium chloride (NaCl). Sodium chloride consists of forty percent sodium ions (Na+) and sixty percent chloride ions (Cl-). Because of its solubility, chloride poses a great danger to both aquatic and land organisms and plants. Furthermore, no natural method exists to remove chloride from the environment. It does not “biodegrade, does not easily precipitate (react with other ions to form a solid), does not volatilize (turn into a gas), is not involved in biological processes, and does not absorb (adhere) significantly on mineral surfaces.”
Although not as mobile as chloride, sodium can substantially affect the quality of drinking water for both humans and wildlife. In an EPA-mandated study, researchers recognized sodium concentrations from road salt as a potential “problem for drinking water systems” and a developing environmental concern. It is much easier for soil particles to absorb sodium, so it is less likely that sodium will reach as much ground water and surface water as chloride; if absorption does not occur, however, sodium will gradually enter the water systems.
How Road Salt Works
Road salt decreases the freezing temperature of water, which helps prevent ice and snow from sticking to the roads. It is an “endothermic” chemical, meaning that it needs to absorb heat from its surroundings in order to dissolve. Road crews deposit road salt on snow-covered roads in amounts that allow it to reach the pavement, breaking the connection between the snow or ice and the pavement, thus making it easier for plows to clear the roads. Road salt, however, does not effectively work at every temperature. At higher temperatures, less road salt is needed to melt a large quantity of snow or ice. At lower temperatures, though, a large amount of salt is needed to melt just a small amount of snow or ice. Further, road salt alone is only efficient at temperatures ranging from thirty-two to about fifteen degrees Fahrenheit.
In temperatures below fifteen degrees Fahrenheit, road maintenance crews add or substitute other chemicals such as magnesium chloride (MgCl2) and/or calcium chloride (CaCl2) to increase the effectiveness of road salt. These chemicals perform much better in temperatures below zero degrees Fahrenheit. Both of these chemicals are “exothermic,” meaning that instead of requiring heat from their surroundings in order to dissolve, they emit heat as they dissolve. These chemicals, however, are not any less corrosive or environmentally damaging than standard road salt.
The Problem
Deicing chemicals such as sodium chloride enter the roadside environment in a number of different ways. Following its applica-tion to the roadways, road salt may dry and moving vehicles may blow it off the road. It may also remain on the road until a rain- fall occurs, combine with the water, and splash off the road when vehicles pass by. The largest quantity of deicer, though, enters the outside environment through runoff. Most often, snowplows push the chemicals off the road, or the deicer forms a solution and trickles off the roadways. The chemical concentration contained in the deicer is greatest in the runoff after the first rainfall. This “roadway runoff” can then accumulate in ditches, drainage pipes, or any other permeable area and enter the nation’s lakes, rivers, streams, and soil.
Presently, many streams in the northeastern part of the United States are in danger of becoming toxic to “sensitive freshwater life” within the next 100 years due to high levels of chloride. Much of the chloride contamination in the waterways is because of the use of road salt in these areas. According to Sujay Kashual, a researcher at the University of Maryland’s Center for Environmental Science’s Appalachian Library, and several other researchers, “Salt contamination is ‘one of the most significant threats to the integrity of freshwater ecosystems in the northeastern United States.’” Kashual and a team of researchers studied thirty years of data from rural streams in Baltimore County, Maryland, the Hudson River Valley, New York, and the White Mountains, New Hampshire, as well as five years of data from streams in the urban regions of Baltimore, Maryland. The results of the study showed an increase in chloride levels in rural streams over the past twenty years, with levels doubling in areas of New York and New Hampshire, and quadrupling in Baltimore County. In addition, urban areas of Baltimore contained many streams with chloride levels over the 0.25 gram/liter limit, which are levels dangerous to freshwater organisms.
In Pennsylvania, researchers have discovered that sodium levels in the Delaware River have almost tripled over the past sixty years, and chloride levels have increased by five times. Hongbing Sun, a professor of geological and environmental sciences at Rider University, concluded that road salt is primarily responsible for the increasing levels of sodium and chloride in the Delaware River. Furthermore, the Schuylkill River has experienced increases in its salt content as well. In fact, Chris Crockett, the director of planning and research at the Philadelphia Water Department, estimates that “‘[I]n my lifetime, we’ll see the Schuylkill hit its carrying capacity.’”
Pollution from road salt can cause a host of problems for animal and plant species living near roadway areas and in contami- nated waterways. Studies have shown that chloride contained in road salt has the potential to “negatively impact the survival rates of crustaceans, amphibians such as salamanders and frogs, fish, plants, and other organisms.” High amounts of chloride are dangerous to these organisms because chloride affects the organisms’ ability to control their salt intake.
Additionally, “highly concentrated road salt” may bring about the dehydration and death of nearby plants and trees because it inhibits their ability to absorb water. One study even found that chloride from road salt can cause “invasions of non-native plant species” that are much more tolerant of salt than the plants presently located by the roadsides. Taken together, all of these existing and potential problems are now prompting individuals and communities around the nation to ask what they can do to help slow the contamination process.
III. PRESENT STATE OF REGULATIONS A. Federal Regulations
The Federal Water Pollution Control Act of 1948 was the first key federal law concerning water pollution. In 1972, due to in- creasing knowledge and apprehension surrounding water pollution, Congress amended the statute to include a number of additional regulations. This new law became known as the Clean Water Act (CWA).
The CWA includes provisions which “maintain[ ] existing requirements to set water quality standards for all contaminants in surface waters” and “ma[ke] it unlawful for any person to discharge any pollutant from a point source into navigable waters, unless a permit was obtained under its provisions.” Under the CWA, the term “point source” refers to any identifiable source, such as a pipe or drain. The term “navigable waters” is defined as the “waters of the United States.”
The CWA requires states to separate waterways according to their “intended use” and to create a State Implementation Plan (SIP) to make certain the quality of the water meets the CWA’s standards. The amount of pollution in each separate waterway must be low enough that the water is able to support its “designated use.” The CWA mandates that states must update their water quality standards every three years.
Although environmental groups in Pennsylvania concerned about chloride’s effects have brought their concerns to the Penn- sylvania Department of Environmental Protection (PA DEP), chloride is still not a regulated substance in Pennsylvania. In Pennsylvania and in many other states, chloride level regulations remain absent from the water quality standard updates. Additionally, many states treat road salt as non-point source pollution, because trucks apply it to roads where water then washes it away. States, therefore, do not need to obtain a permit for its application or discharge.
B. State Regulations
Road salt storage is a regulated activity in many, but not all, states. In states like Ohio where road salt storage is not presently regulated, reports have emerged describing road salt’s pollution of the water systems. An article from Columbus, Ohio, reported that the Ohio EPA found five instances of polluted wells due to salt contamination.
In response to findings like those in Ohio, states have begun to take road salt contamination more seriously and are now looking at how to improve road salt storage and application. Following the recent discovery of contaminated waters in Ohio, the Ohio Water Resources Council formed a committee to determine how other states have handled salt storage and what Ohio should do going forward. The committee examined regulations in sixteen states across the United States, including the mid-Atlantic states of Pennsylvania, New Jersey, and New York. Specifically, it analyzed which regulations existed regarding storm water programs, water supply protection, and groundwater protection.
Many states consider the mixture of water and salt formed when rain or melted snow travels down salt piles to be contami- nated storm water, thus falling under storm water permitting requirements. Seven of the sixteen states employ a “basic approach” to road salt storage. This “basic approach” involves using the state’s storm water program in some capacity to regulate storage of road salt. These storm water programs usually include the following: “(1) [a] municipal separate storm sewer permit (MS4); (2) [an] industrial multi-sector general storm water permit; (3) discretionary authority; and (4) [a] characterization and abatement of unpermitted discharge.”101 The remaining nine states use either a modified “basic approach” or a wide-ranging regulatory system that does not require storm water regulations.
Pennsylvania restricts its regulatory coverage of salt storage to storm water programs and responses to unauthorized discharges. In Pennsylvania, the PA DEP is responsible for promulgating regulations regarding salt storage. The authority for the PA DEP’s requirements comes from its National Pollutant Discharge Elimination System (NPDES) permit. Under the PA DEP’s regulations, salt piles weighing less than 3,000 tons must be regulated according to the Salt Institute’s Salt Storage Handbook. At the very minimum, a “permanent structure” must cover these piles, and the piles must be located on an “impermeable base.” For piles weighing over 3,000 tons, regulations must follow the Salt Institute’s guidelines in its Voluntary Salt Storage Guidelines for Distribution Stockpiles. At a minimum, “these piles should be covered with canvas, polyethylene, or other synthetic material, except when receiving salt, building the stockpile, or loading out to customers.” Like the lighter piles, these piles must also have an “impermeable base.”
New Jersey, like Pennsylvania, does not have a specific program in place for the regulation of salt storage. New Jersey follows a MS4 system in which crews must store certain piles in a permanent storage building. As of February 2013, the State was negotiating with the salt industry to create permit requirements for five commercial piles that had escaped regulations.
In contrast, New York enacted a program separate from its storm water program to regulate salt storage in the state. Under this approach, regulations exist pertaining to certain point and non-point sources in limited municipal water supply watersheds. These regulations only provide that piles located in those areas “may” require some type of covering, not that a covering is mandatory.
IV. NEW DEICING TECHNIQUES
In light of the many problems caused by the substantial use of road salt, communities have attempted to develop and implement more environmentally friendly deicing methods. In order to decrease their reliance on road salt, various agencies are using what is known as “anti-icing” or “pre-wetting” techniques. These methods involve pre-treating the roads with “salt brines” before a winter storm arrives. Wetting the salt before use helps more of it stay on the roads, instead of running off into the wayside. This method is also more cost-effective because it begins to work immediately, thus helping to prevent ice from forming and lessening the amount of salt needed. Sand is also a common material used in combination with road salt, especially at very low temperatures. Sand increases automobile traction and allows for better travel when roads become very icy.
Another increasingly popular technique is the use of beet juice on the roads. Recently, the Pennsylvania Department of Trans- portation (PennDOT) announced that it was experimenting with beet juice as a way to melt ice and snow when temperatures dip close to zero degrees. Bob Skrak, a PennDOT spokesperson, stated that mixing beet juice with road salt could greatly increase the effectiveness of road salt at temperatures even “‘. . .well below zero— maybe 15, 20 below.’” In addition to Pennsylvania, about 175 municipalities in the Midwest have begun to use a product called “Beet Heet” to help fight the large amounts of snow and ice received this past winter.
A number of communities have turned to even more bizarre alternatives to using road salt. In some parts of Wisconsin, re- sidents have used cheese brine mixed with salt as a deicer. Representatives from Polk County, Wisconsin, reported a savings of $40,000 in its first year of use and have stated that this method “saves 30% of salt by eliminating the bounce factor.” Other towns have been experimenting with molasses, mixing it with a salt brine solution to help salt stick to roads. Molasses also helps to decrease the “corrosive qualities” of chloride. Even more interestingly, a town in Iowa used a mixture of garlic and table salt to deice its roads. Additionally, a company in Canada has developed a product called “EcoTraction,” which is made from non-toxic volcanic rock. The granules of this product implant themselves into snow and ice, producing a “solid, non-slip surface.”
Some communities have also experimented with or considered the use of much more expensive techniques to deal with the detrimental environmental effects of road salt. For example, the state of Indiana has developed computers for its plowing trucks that tell operators the exact amount of salt they should apply under specific weather conditions. The State reported that this new technology saved it 228,000 tons of salt and thirteen million dollars in salt and overtime costs in just one winter. One town in Minnesota is currently experimenting with a “pervious pavement surface” that would allow for melting snow and ice to sink right through the roads instead of running off into the roadside. Further, some researchers have suggested developing newer and more efficient plow blades as well as creating heat-tubing systems under roads to melt snow and ice more effectively.
Lastly, engineers and scientists have considered the idea of developing roads equipped with solar panels that would assist in melting the snow and ice, making it easier for crews to clear the roads. Solar Roadways, an Idaho company, is using a $750,000 research contract from the Federal Highway Administration to help develop this solar powered pavement technology. Researchers estimate that this technology could be available within the next three to five years and would be primarily used in large spaces like parking lots.
These environmentally conscious techniques, however, are not without their faults. In communities experimenting with beet juice, for instance, residents have complained that the juice stains their tires and roads and smells like “rotting vegetables.” Bacteria that decompose the beet juice also use up oxygen, which contributes to the already low oxygen levels in many urban areas. Furthermore, substituting beet juice for cheaper materials like salt brine may cost communities nearly ten times more.
Cities that use sand have found that it requires specific conditions to work properly. Specifically, crews can only apply sand to areas of low traffic because high volumes of traffic will cause sand to fly off the roads. In addition, sand may cause damage to automobiles by cracking their windshields and deteriorating rusty metal. Crews using sand also need to remember that it only improves vehicle traction; it cannot contribute to the actual deicing of the roadways.
V. THE REAL QUESTION: WHAT IS THE BEST APPROACH?
The reality of the situation is plainly that salt is just the least expensive and effective solution available. With the high demand for clear roads and expectations of a quick deicing process, salt has proven to be the most appropriate material for the job. It is unlikely that salt will ever completely vanish from the United States’ winter deicing scheme. Municipalities and researchers, therefore, must focus on ways to decrease its use, without attempt- ing to entirely eliminate salt use from the nation’s winter deicing routine.
A 2011 study concluded that a “‘reduction in usage appears to be the only effective road-salt-runoff management strategy.’” Many of the aforementioned methods of deicing fulfill this need, but they are only in the early stages of development. Thus, re- searchers and engineers need to continue to study these new practices in order to improve their effectiveness and practicality.
Another way to possibly decrease the amount of salt applied to the roads is through training programs for salt crews. During this training process, supervisors should advise their crews of the dangers of over-applying road salt when they are uncertain about how much to use. Steven Lund, maintenance engineer at the Minnesota Department of Transportation, stated that the state has seen its “biggest return on efforts to protect the environment” from its preparation of salt crews. Similarly, Roger Bannerman, water resources management specialist at the Wisconsin Department of Natural Resources, agrees that the only way to decrease road salt use is to, “‘educate, educate, educate.’”
VI. FUTURE IMPACT
Despite the overwhelming evidence that salt contamination is a very real and current problem, not everyone is willing to recognize it as such. In fact, the PA DEP has stated that salt is “not really” a problem in the quantities crews apply it to the roads. The PA DEP asserts that winter water levels are high enough to dilute the salt content. It seems likely that similar attitudes toward salt contamination have contributed to the non-existent or sparse chloride and salt storage regulations across the country. Lawmakers need to better monitor each state’s use of road salt and recognize the need for more specific regulations.
In addition, lawmakers should remember that private operators also apply road salt to various other types of properties, such as private parking lots, streets, and walkways. Private operators contribute significantly to the amount of road salt used in the country each year. In fact, officials in the city of Madison, Wisconsin, found that private operators apply about twice the amount of road salt than the city applies annually. Not only should training and regulatory programs include public road crews, but they should incorporate these private operators as well.
Problems may arise, however, in the implementation of future road salt regulatory policies. One possible major policy debate in the coming years is whether states should mandate that road crews and private operators use more environmentally friendly al- ternatives to road salt. This decision will most likely involve a thorough cost-benefit analysis, weighing the cost of continued use of standard deicers like road salt against the perceived benefit of using more eco-friendly materials. It is clear that road salt has already begun to substantially impact the nation’s ecosystems, so the question remains as to how much environmental damage citizens and lawmakers are willing to tolerate in the future. As of 2004, environmental damage from road salt and other deicing chemicals reached estimates as high as five billion dollars; this number has likely only increased since then.
A further problem may arise if some states do decide to mandate the use of alternative deicing strategies, while others choose not to implement an alternative program. Inconsistency among states can cause traffic problems and concern among drivers who hold differing expectations about how snowy and icy roads should be cleared. To help prevent this problem, lawmakers and state transportation officials must come together to discuss their own alternative deicing successes and attempt to standardize future regulations among states. Although many individuals and officials have begun to recognize the necessity of taking action to remedy the damage created by road salt use, many questions still exist about the true extent of damage and how to best implement a management program. It is likely that future regulatory processes regarding standard deicers such as road salt will depend heavily upon new research and the development of new alternatives.
-Sara Labashosky, Villanova University School of Law