Chloride Crisis: My Journey of Learning

Marialuna Schreiner Cintrón
Missouri River - credit Travel Montana

The Salt Watcher of the Month for February 2023 is Marialuna Schreiner Cintrón! Marialuna is a high school senior in Kansas. She first started road salt research and advocacy her sophomore year, and ever since has been researching road salt online; talking with city officials and scientists about obstacles and solutions to chloride toxicity in Kansas City, MO's waterways; and taking chloride samples with Salt Watch's chloride test strips. An avid Salt Watcher, Marialuna looks forward to working with the environment as a career. This is what she had to say about her journey with Salt Watch.

In 10th grade, I had a small midlife crisis. I learned about road salt, which reduces car crashes and keeps us safe in the winter — but that’s not all that it does. When my mom told me that road salt poisons creeks and waterways, I couldn’t stop thinking: “Who will do something?”

With the enthusiasm of “We are the next generation!” and a small petition (gaining 138 signatures), I wholeheartedly believed that I could single-handedly make Kansas City, Missouri (KCMO) use less road salt and switch to more eco-friendly salt alternatives so that less chloride is leached.

When I started doing serious research, my pride deflated with the complexity of the road salt issue. There are many environmental groups concerned about road salt in northern states, but hardly anyone seemed worried in the Midwest. I also noticed that there were no resources directed to salt reduction in Kansas City, and much more attention seemed to be given to road salt in northern states.

As I’ve learned, it is next to impossible to remove road salt once it is in soil or water. Additionally, EPA does not regulate chloride levels in non-drinking water. To make matters even worse, eco-friendly alternatives are much more expensive than regular road salt. Dr. Jing Tao, Senior Environmental Officer at KC Water, said that they have budget constraints, and while they’re trying to explore alternatives to road salt (like beet juice), they have not found anything that will work as effectively as traditional road salt at the same price.

That is around 270,000,000 pounds of road salt used on Kansas City-area roadways per year, year after year. How could that amount of salt not affect waterways?

Later, another environmental officer from KC Water said that based on their data, “the Missouri River/select streams have not gotten saltier in the past six years, and aquatic life in select streams have not declined.” But this felt odd. The Public Works Director had told me previously that in the 2020-2021 winter, KCMO used 27,000 tons (54,000,000 pounds) of road salt. Extrapolating to the entire KC metro area and assuming this figure was typical, that is around 270,000,000 pounds of road salt used on roadways per year, year after year. How could that amount of salt not affect waterways?

I did some digging into KCMO’s Stormwater Management Plans to find out if chloride is somehow being removed or prevented from entering the waterways. What I found: lots of guidelines, 18 bioswales (each of which filter a tiny fraction of runoff in a city of 300 square miles), and no other chloride data or prevention projects.

So, I started measuring chloride levels with test strips from the Izaak Walton League’s Salt Watch program. My readings averaged 112 parts per million (ppm), well below EPA’s drinking water standard of 250 ppm. This seemed to suggest that chloride might not be a concern after all.

But I still wasn’t done. Widening my search, I found the United States Geological Survey (USGS). Lo and behold, Steven Corsi, a Wisconsin research hydrologist, had tried to answer my exact question. I asked Corsi, “KC uses tons of salt and does little prevention. When I do my own tests, chloride levels seem ‘normal.’ Am I missing something?”

Corsi responded, “Many agencies that collect water quality data do not sample during the winter, or if they do, they are not sampling during road salting (deicing) or runoff events. It is critical that samples are collected during these events. Sampling even a few days later will miss the highest concentrations.”

I tried Corsi’s suggestion and tested for chloride the very same day salt was put on the roads. The results were shocking. The first test resulted in 341 ppm of chloride. The second test, a couple hundred feet from the first location, was 637+ ppm. These were 1.4 and 2.5 times higher than EPA’s drinking-water standard, respectively.

I tried a hydrologist’s suggestion and tested for chloride the very same day salt was put on the roads. The results were shocking.

Based on this, it is sensible to assume that streams and rivers have peak chloride concentrations, further emphasizing the need to test during road salt runoff and throughout the year. Furthermore, knowing that peak concentrations do exist, and knowing how often they happen, could push organizations — like KC Water — to take action based on better evidence, instead of based on chloride tests taken at the wrong time. Knowing this might motivate KC Water to increase their efforts, think outside the box, and find a creative solution to reduce road salt.

Through my salt journey, I’ve learned that government workers are saturated in various tasks, incentives, and budgets that keep them stuck. They aren’t the bad guys; they are simply swamped.

What is the next step in my road salt journey? I am continuing to test for chloride with the help of Salt Watch, as well as keep in touch with city officials and scientists to keep an open dialogue. This has been a wonderful learning journey. Sometimes having a small midlife crisis is good!

Get started with Salt Watch

Top photo: The upper Missouri River at Gates of the Mountains, western Montana, north of Helena. Credit: Travel Montana.

Newsletter Sign Up