Discover The Montana Town With The State’s Worst Air Quality

Written by Justin Zipprich
Updated: May 25, 2023
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Every year, people around the country become more concerned with environmental issues like climate change and global warming, and they want to know that they are living their best possible lives. Part of that concern is the air quality where they live. Every state has a city with the worst air quality, and today, we will be talking about the state of Montana. We’ll tell you about the Montana town with the state’s worst air quality. Plus, we’ll let you know what constitutes bad air, how it affects the people and animals that live there, and share other important facts.

The Montana Town With The State’s Worst Air Quality Is Heron

When it comes to cities in Montana, Heron is famous for all of the wrong reasons. Among them is the fact that it is ranked by as the Montana town with the state’s worst air quality. With a score of 45.5, it is just above the second and third-place finishers of Troy, Montana, and Noxon, Montana.

Heron is a small town of just 245 people at the time of this writing. Although it seems small, this population number is actually a 64.43% increase since 2000. However, keep in mind that many cities and towns in Montana are smaller in population density since most of the state is unpopulated. Altogether, Heron has just over five square miles of land area. 

A couple of other interesting facts about Heron, Montana is that the average household income is just above $42,000, the median home value is about $173,000, and the public school quality is just a notch below the state’s average. More about that later.

What Makes Heron The Montana Town With The State’s Worst Air Quality?

A beautiful landscape of the Hyalite reservoir in Montana

Lead, carbon monoxide, and other harmful pollutants can fill the air and cause a lot of harm.

©Wirestock Creators/

The findings about the air quality in Heron come from the Air Quality Index (AQI). Essentially, the AQI are numbers created and used by the government to determine the air quality for a given location. The higher the number, the more likely it is that the people in that town will experience health issues due to the environment. There are many factors that make up the AQI of a particular town. 

Specifics About The AQI In Heron, Montana

Below are the factors that go into determining the air quality of each city and the numbers that we see in the town of Heron, Montana:

Description and Specifics

  • Average Air Quality By Years (How the air quality in Heron compares to the other cities in Montana and to the national average).
    • From the years of 2000 until 2007, the air quality in Heron was much worse than in the rest of the country and the other towns in Montana. The quality has improved in recent years, and it is currently right around the U.S. average.
  • Total Suspended Particulate (The total harmful particles in the environment)
    • There have been ups and downs as far as the suspended particulate over the years. Recently, as of 2009, the particles have increased and are far above the U.S. average.
  • Lead in the Environment (The measurement of lead found in the atmosphere)
    • Lead findings have reduced greatly as of 2001. Currently, lead numbers are equal to the Montana and U.S. averages.
  • Carbon Monoxide Findings (The measurement of carbon monoxide found in the environment)
    • The good news is that carbon monoxide has decreased over the years. However, it is still above the average numbers of the state and the country.
  • Sulfur Dioxide (SO2 found in the air)
    • As of 2006, the sulfur dioxide in the air has decreased to be below the state and U.S. averages.
  • Nitrogen Dioxide (NO2 found in the air)
    • The Nitrogen Dioxide numbers have decreased over the years. As of 2009, the numbers are right in the middle of the state and U.S. averages.
  • Ozone (Gas exposure in the air)
    • Ozone numbers have gone up and down over the years. As of 2009, the averages in Heron are below both the state and U.S. averages.
  • Particulate Matter (Harmful particles found in the air)
    • This measurement looks at particles of 10 micrometers or less and 2.5 micrometers or less. In both cases, the numbers in Heron are above both the state and U.S. averages.

Keep Numbers in Perspective

Keep in mind that these numbers change over time. Just because the air quality in Heron is the worst in the state, it doesn’t mean it is completely inhabitable. Remember, every state has to have a city with the worst air quality.

Where Is Heron, Montana Located On A Map?

Heron, located in Sanders County, is in the western region of the state. It is between the Cabinet and Bitterroot Mountains, which border Idaho. The closest city is Noxon. Montana is located in the Mountain West region in the northwest of the United States. It shares a border with Idaho to the west, Wyoming to the south, North Dakota and South Dakota to the east, and the following Canadian provinces to the North: Alberta, British Columbia, and Saskatchewan.

Other Cities To Consider

While Heron is on the top of the list as far as poor air quality, there are other Montana cities that are almost as bad. The other five towns that makeup numbers 2-5 as far as poor air quality are:

2. Troy, MT

3. Noxon, MT

4. Dillon, MT

5. Hebgen Lake Estates, MT 

Meanwhile, there are several towns that are at the bottom of the list, meaning that they have great air quality compared to Heron and other similar towns. When you visit these areas, you can notice a fresh difference when compared to Heron and Troy. Some of the Montana towns with the best air quality include those listed below. They are all tied at #428 on the list.

  • Floweree, MT
  • Valier, MT
  • Ledger, MT
  • Pendroy, MT
  • Black Eagle, MT
  • Rollins, MT
  • Dayton, MT
  • Niarada, MT
  • Gildford, MT
  • Bynum, MT
  • Carter, MT

How Poor Air Quality Affects The People Of Heron

The fact that Heron is the Montana town with the state’s worst air quality means that the people there need to understand their situation and learn how to protect themselves from environmental harm. At the time of this writing, there are 245 people in the town of Heron, but the fact that there are fewer people doesn’t mean they aren’t in jeopardy. 

Air quality is so poor because there are tiny particles of lead, carbon monoxide, and the other harmful materials listed above. The articles are so small that we inhale them without even knowing, and that can cause initial issues, like shortness of breath, wheezing, coughing, chest pain, and fatigue.

If the people there already suffer from some of those minor conditions, they can get worse and lead to serious ailments, including asthma, COPD, and cardiovascular and heart disease. Constant exposure to poor air quality over several years can cause ongoing health issues, like itchy eyes and eventual lung disease, cancer, or even death.

While everyone can be affected, certain groups may be more susceptible to the dangers of poor air quality, including infants, young children, adults over 65, people who regularly smoke, and folks who live in poverty. 

The poverty issue is a major factor for several reasons. One is that if you don’t make a lot of money, then you may not be able to afford health insurance or properly take care of your existing issues, and so exposure to harmful chemicals can only make things worse. There’s also the fact that individuals who are homeless or need to work longer hours outside can also be more exposed. It can be a bad situation, so caution is always necessary.

Poor Air Quality Also Affects The Animals

Animal, Animal Themes, Animal Wildlife, Animals In The Wild, Bear

Harmful pollutants in Heron, Montana can affect wildlife, including bears and bison.


It isn’t only humans that get hurt by the fact that Heron is the Montana town with the state’s worst air quality. It also affects the animals. Fish, mammals, birds, and insects will all be negatively hurt by this issue. Montana is known for its many wide-open spaces that are filled with animals, so this is a major cause for concern.

Land Species

There are many land mammals and species that are commonly found in the state of Montana. A sampling of them includes:

The animals that walk the land in Montana are also subject to the same issues associated with bad air quality as humans. They can also breathe in bad air and have internal organ issues. Also, when the chemicals in the air are digested by animals within a larger preditor’s food chain, then they can also get the illness that the other animal had. 

Water Species

There are also many fish and water creatures that are commonly found in Montana. The list is vast, but a small list includes:

  • Catfish
  • Goldeyes
  • Killfish
  • Pikes
  • Salmon
  • Trout-perch
  • Sunfish
  • Sculpins
  • Gars
  • Sculptures

When the bad air particles get into the water, they can also harm the fish. Pollutants are bad for all living things, including those in rivers and oceans. Plus, if other animals eat these fish, they will also be poisoned. Also, poor air quality creates an increased chance of acid rain, which causes pH levels to fluctuate, and that can also cause respiratory issues for fish and amphibians. This is why it’s important that our air is clean for the good of every living thing on the planet.


The many domestic pets in Montana are also affected by poor air quality. Once the pollution gets into homes, it tends to stay there. Since dogs, cats, birds, and hamsters are indoors a lot of the time, they are constantly exposed to pollutants. Because of that, many pets can be susceptible to nose and throat elements, including bronchitis and asthma. To protect their health, pet owners should have a humidifier running in the home, especially if they live in a town with poor air quality, like Heron. 


When birds fly in the air, they allow these pollutants into their air passages. As it is, birds have a higher breathing rate than humans, so the conditions are made worse. Also, when the birds are negatively affected, they tend to have lower egg production and reduced body size, so it is nearly impossible for them to repopulate, which can kill off many species.


Flowers, crops, and plants, in general, are also affected by poor air quality. Ground-level ozone can damage leaves and cause them to turn yellow and lack proper chlorophyll production. Pollution and smog can also hinder flowering and damage the roots, which stops the plant from growing. Many animals eat these plants to survive, and if they are infected, then so can the animals.


Now you know that Heron is the Montana town with the state’s worst air quality, and you also know why it’s so important to have a part in the discussion about climate change. While the air quality in Heron won’t cause immediate death, it is a cause for concern for humans and animals alike, so we must pay attention. Make it a point to reduce pollution in your life, and you can make a difference for people around the world.

The photo featured at the top of this post is © Leo_nik/

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About the Author

Justin Zipprich is a writer at A-Z Animals, where his primary focus is travel, state facts, pets, and mammals. Justin has been writing and editing animal content for over 7 years, though he holds a Bachelor’s Degree in Instructional Technology from Western Illinois University, which he earned in 2005. As a resident of Texas, he loves discovering local animals and spending time with his wife and two kids.

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