Mississippi River Water Quality
The Mississippi River is the main source of drinking water for about 18 million Americans in 50 cities throughout the U.S.
That’s a whole lotta agua!
It also means there’s a lot of opportunities for pollution from nasty contaminants.
Exactly how safe (or unsafe) is Mississippi River water quality?
Keep reading to find out…
The mighty Mississippi flows almost the entire width of the country, from Minnesota in the north to the Gulf of Mexico in the south.
It drains into 31 states and touches about 40% of the lower 48’s total surface area.
The river is also a migratory flyway for 40% of all North American waterfowl and shorebirds, and is home to 260 species of fish, 50 species of mammals, and 145 species of amphibians and reptiles.
In other words, if Mississippi River water quality suffers, the country suffers.
It also serves as an important transportation route for commerce and industry.
For example, billions of dollars worth of goods travel down the river every year, along with roughly 60% of the grain exported from the U.S.
Some sections of the Mississippi River have high levels of contaminants like bacteria, mercury, and PCBs.
These pollutants can have damaging effects:
- Bacteria threaten human health and limit recreational use.
- Phosphorus increases the risk of algae blooms.
- Sediment and nitrate affect aquatic life and also increase the risk of algae blooms.
- Chloride runoff from deicing salt on winter roadways
- pose a long-term threat to aquatic life.
- Pesticides can make water undrinkable and harm wildlife.
- Microplastics are an emerging health concern for humans and animals.
- Other contaminants like pharmaceuticals, mercury, PFOS, and triclosan are an ongoing threat.
Let’s take a closer look at the effects these contaminants have on Mississippi River water quality:
Parts of the Mississippi River are contaminated with high levels of bacteria like E. coli.
These pathogens not only make the water unsafe to drink, but they can also make it too dangerous to swim in.
E. coli, or Escherichia coli, usually indicates the presence of other other bacteria as well.
Bacteria comes from human and animal feces.
Some of the main sources of bacterial contamination in the Mississippi River are:
- Septic systems
- Storm and sanitary sewer overflows
- Leaky sewers and septic tanks
- Feedlots
- Grazing livestock
- Manure applied to fields as fertilizer
- Pets and wildlife
In rural areas, agriculture tends to be the main source of contamination, but in urban areas, human sources are usually the cause.
Drinking bacteria-contaminated water can cause symptoms like:
- Nausea
- Vomiting
- Fever
- Headache
- Diarrhea
Fecal bacteria can survive for long periods of time in sediment before spreading to main drinking water sources.
E. coli levels are typically highest near the tributaries that feed into the river.
For example, in Minnesota the sections of the river that are downstream of the Crow River in Dayton tend to have higher bacteria concentrations.
Phosphorus is a common element in the environment that is important for plant growth, and it’s a key ingredient in fertilizers.
Some of the main sources of phosphorus in the Mississippi River include:
- Agriculture
- Steambank erosion
- Wastewater treatment plants
- Atmospheric deposition
- Failing septic systems
- Some road salt alternatives
Phosphorus levels are usually the highest in summer months due to agricultural activities.
Historically, wastewater treatment plants have been one of the biggest sources of phosphorus pollution.
However, in recent years treatment plants have reduced phosphorus production by up to 88% in some areas.
This is great news, because too much phosphorus can make water unsuitable to drink and unsafe to swim in.
Plus, it can harm aquatic life by feeding the growth of algae and increasing the risk of dangerous blue-green algae blooms.
Algae blooms deplete oxygen levels in the water and suffocate fish — they can also be life threatening to pets that swim in the contaminated water.
Side effects of exposure to algae-contaminated water include:
- Stomach ache
- Nausea
- Vomiting
- Diarrhea
- Headache
- Fever
- Skin rash
- Throat irritation
Higher levels of sediment in the water can increase phosphorus concentrations, because phosphorus attaches to soil particles.
What can you do to help protect Mississippi River water quality from phosphorus contamination?
For starters, use lawn chemicals sparingly, and use phosphorus-free dishwashing detergents and soaps.
You can also help by picking up pet waste and keeping grass clippings and leaves out of storm drains.
Sediment pollution is tiny particles of soil and organic matter that are suspended in the river’s water.
Sections of the Mississippi downstream of tributaries tend to have more problems with excess sediment.
This is because these smaller rivers and streams have higher concentrations of loose soil and organic matter.
This is bad news, because sediment can trap and carry contaminants.
The excess sediment also makes water murky, which blocks sunlight and damages aquatic plants.
Nitrate, like phosphorus, is another common ingredient in fertilizers.
Overall, nitrate’s effects on Mississippi water quality has increased significantly over the last few decades.
The main factors of nitrate contamination are:
- Agricultural production
- Fertilizer application
- Farm drainage systems
- Wastewater management
- Higher overall river flows
Nitrate contamination in drinking water can cause health effects like:
- Increased heart rate
- Nausea
- Headaches
- Abdominal cramps
- Increased risk of gastric cancer
However, the most dangerous health concern is a life-threatening condition called methemoglobinemia, also known as blue baby syndrome.
Blue baby syndrome occurs when babies drink formula made with nitrate-contaminated water.
Nitrate inhibits the blood's ability to carry oxygen, turning the skin a bluish color.
Infants under six months are most at risk.
Excess nitrate also threatens aquatic life…
For example, nitrate is a primary contributor to the “dead zone” in the Gulf of Mexico, where nitrate concentrations have increased by 44% since 1976.
Like phosphorus, nitrate feeds massive algae blooms each year.
When the algae die and sink, they starve the bottom water of oxygen and suffocate marine life.
Chloride is the main ingredient in road deicing salts and water softeners.
Worst of all, some deicing salts contain iron-cyanide compounds to prevent caking.
These compounds can break down when exposed to sunlight and form free cyanide, which is one of the most toxic substances to human and aquatic life.
Other sources include fertilizers, dust suppressants and landfill leachate.
Just one teaspoon of chloride salt is enough to pollute five gallons of water!
Most of the Mississippi River meets regulatory levels for chloride, but levels are higher in metro areas where road deicers are more widely used.
At high concentrations, chloride can be toxic to aquatic wildlife.
Plus, it also affects groundwater and drinking water supplies.
Worst of all, chloride is a permanent pollutant and does not degrade over time, so once it’s in surface water like the Mississippi River, it’s there to stay.
However, you can remove it from drinking water by installing a filter in your home, but more on that later…
Many sections of the Mississippi River have ongoing issues with contamination from pesticides and herbicides.
Pesticides and herbicides are chemicals used to control unwanted insects, weeds and other pests.
At elevated levels, they can cause dangerous health effects and harm wildlife.
Acute symptoms of consuming pesticides in drinking water include:
- Headache
- Nausea
- Dizziness
- Sweating
- Salivation
- Twitching
- Weakness
- Vomiting
- Abdominal cramps
- Diarrhea
Long-term consumption of pesticides can also increase the risk of cancer.
Some of the most common pesticides and herbicides are atrazine, acetochlor, chlorpyrifos, and metolachlor.
Atrazine hit the market in 1954 for weed control in corn production.
Since then, it has possible links to prostate cancer and other cancers in humans, as well as damaging effects on fetal growth in pregnant mothers.
Acetochlor is another probable human carcinogen, and all pesticides have toxic effects to birds, fish, and insects, including bees.
Microplastics are tiny pieces of plastic that break down in the environment from water bottles and other consumer products.
Over time, they wash down storm drains and into local drinking water sources, including the Mississippi River.
Microbeads are another major source of microplastics.
You might know them from being added to facial washes, toothpastes, and other products.
Researchers began discovering them in the Mississippi River in the mid-2000s.
These toxins are called “forever chemicals” because once they’re in the environment they’re almost impossible to remove.
Microplastics are found in water bodies and sediment around the world, including ocean sediment up to three miles below the surface!
Microplastics are a risk to wildlife and human health because they contain several toxic chemicals, including BPAs that block hormone receptors and cause hormone imbalances in humans.
They’re also hard to remove from your body once you ingest them.
Studies show that consuming microplastics can lead to intestinal inflammation, damage the gut flora and weaken immunity.
Ingesting plastic particles smaller than 0.15 millimeters can travel into the lymph and circulatory systems, and extremely small particles can even pass through placental tissue to the growing fetus.
Microplastics can also have devastating effects on wildlife…
Exposure to microplastics can decrease growth rates, inhibit egg hatching, and increase death rates from predators in fish.
Oysters exposed to microplastics also may produce fewer and less healthy offspring.
Birds and other animals can also experience damage to their digestive and circulatory system, as well as liver damage and tumor growth.
Mercury is a toxic heavy metal that can damage the nervous system in animals and humans, especially children.
Most of the mercury contamination affecting Mississippi River water quality comes from coal combustion and mining activity.
Mercury pollution in the river peaked in the 1960s, but fortunately accumulation rates decreased significantly over the last few decades.
Side effects of consuming mercury in drinking water include:
- Tremors
- Insomnia
- Mood swings
- Irritability
- Nervousness
- Muscle weakness
- Headaches
- Poor coordination
- “Pins and needles” sensation in the hands and feet
- Impairment of speech and hearing
You can also get mercury poisoning by eating contaminated fish, so be careful to avoid fish from high-mercury waters.
PFOS, or perfluorooctane sulfonate, is part of a group of toxic chemicals called PFCs (perfluorochemicals).
They were created by the company 3M in the 1950s to make products more resistant to stains, heat and fire.
PFOS is common in nonstick cookware, stain-resistant fabric, food packaging, and fire-fighting foam.
Unfortunately, 3M’s headquarters aren’t far from the head of the Mississippi in Minnesota, so PFCs have a long history of contaminating the river.
When ingested, PFOS can cause side effects like:
- Hepatotoxicity
- Neurotoxicity
- Reproductive toxicity
- Immunotoxicity
- Thyroid disruption
- Cardiovascular toxicity
Several pharmaceuticals, including antidepressants and antibiotics, are found in surface water throughout the country, including the Mississippi River.
Pharmaceuticals make their way into the water from human waste and improper disposal.
Never flush your unused medications down the drain!
Unfortunately, most wastewater treatment systems are not designed to remove pharmaceuticals, so many are discharged back into surface waters.
This can have devastating effects on fish and other aquatic wildlife.
Some drugs reduce the fertility of aquatic organisms, alter hormones, and interfere with other reproductive functions.
Triclosan is an antimicrobial compound used in liquid soaps, cosmetics, toothpastes and sportswear.
It’s found in 58% of all U.S. rivers and streams, including the Mississippi River.
Triclosan enters the river mainly through wastewater treatment systems.
When exposed to chlorine and sunlight, triclosan breaks down and forms potentially dangerous dioxins and other substances known to cause cancer.
Ironically, there’s no evidence to suggest that washing your hands with triclosan antibacterial soap is more effective than regular soaps, so the U.S. Food & Drug Administration recommends washing with regular soap instead.
In general, you should avoid swimming anywhere in the Mississippi River within 48 hours of a rainstorm.
This is because the stormwater runoff flushes high concentrations of contaminants into the river.
You should also be extra cautious downstream of storm drain outlets regardless of recent rainfall, and alway rinse off thoroughly after swimming.
Be on the lookout for algae blooms, especially in the late summer and early fall and do not let your dog swim in the river.
As an extra precaution, contact your local water authority for the latest updates on Mississippi River water quality in your area.
The Great Lakes Network of scientists, the Environmental Protection Agency, the National Park Service Water Resources Division, and six other NPS Inventory Monitoring Networks have ongoing research projects to monitor the water quality in the Mississippi River.
Since 2006, they’ve been monitoring a number of pollutants in the ecosystem.
They check for pollutant levels in the blood and feathers of bald eagles because they’re at the top of the food chain.
They also collect water samples at five locations along the river and test for over 260 different pollutants, including:
- Pesticides
- Pharmaceuticals
- Personal care products
- Wastewater indicators
So you get your tap water from the Mississippi River, huh?
With so many pollutants floating around, including pharmaceuticals that water treatment plants can’t remove, you might want to take matters into your own hands…
Fortunately, high quality reverse osmosis (RO) filtration systems can remove up to 99.9% of harmful contaminants.
RO is a special process that eliminates even the hardest-to-remove contaminants by forcing pressurized water through a very fine, semipermeable membrane.
RO systems also combine several other stages of filtration, including:
- Sediment filters to remove dirt, rust, dust and debris
- Activated charcoal filters to remove chlorine, disinfection byproducts, and improve the taste of your water
- Ion exchange resins to remove excess hard minerals
- Polishing filters to remove any remaining contaminants
- Remineralization to add a healthy ratio of minerals back into the water
Cloud Water Filters even use built-in software to track and monitor your water quality 24/7 through an app on your phone.
Are you ready to tell Mississippi water contaminants to take a hike?
