Contaminants Found in Northern Colorado Water Supplies
Many homeowners think city water is completely clean, but Northern Colorado water can still contain contaminants, treatment byproducts, and hard water minerals that affect your health.
According to EWG Tap Water Database reports, water systems in Fort Collins, Greeley, Windsor, Wellington, Estes Park, Loveland, Longmont, Evans, Johnstown, Ault, and surrounding communities have shown detected contaminants, including some that exceed EWG’s health-based guidelines and caused violations.
While many local water systems meet current federal drinking water standards, “legal” does not always mean the water meets health recommendations. That is why more homeowners are searching for water contamination testing, whole-home water filtration systems, reverse osmosis systems, and water softeners in Northern Colorado.
At Origin Plumbing Heating Cooling Electrical, we help homeowners understand what is in their water and choose the right filtration solution for cleaner, better-tasting water.
Where Does Northern Colorado’s Water Come From?
Many homeowners are surprised to learn that much of the water used in Fort Collins, Greeley, Loveland, Windsor, Wellington, Longmont, Evans, and other Front Range communities doesn’t originate locally.
In fact, about 80% of Colorado’s natural streamflow originates west of the Continental Divide on the Western Slope, while approximately 80% to 90% of Colorado’s population lives east of the Divide along the Front Range. To meet the growing demand for water, Colorado relies on an extensive network of reservoirs, tunnels, canals, and pump stations known as transmountain diversions to move water through and beneath the Rocky Mountains.
Water from the Colorado River Basin and other Western Slope watersheds is transported across the Continental Divide and delivered to communities throughout Northern Colorado. Along the way, water may pass through multiple reservoirs, treatment facilities, pipelines, and distribution systems before it reaches your tap.
While these engineering systems help provide reliable water to millions of Colorado residents, the water can still contain naturally occurring minerals, treatment byproducts, and other contaminants that homeowners may want to address with a water filtration system or water softener.
That’s one reason many homeowners in Fort Collins, Greeley, Windsor, Wellington, Loveland, Longmont, Estes Park, Evans, Johnstown, and Ault choose to have their water tested and install whole-home water filtration systems to improve water quality, taste, and overall peace of mind.
Why This Matters
Because Front Range communities depend on multiple water sources, reservoirs, and treatment processes, water quality can vary significantly from one city to another—and even from one neighborhood to the next. A professional water test is the best way to determine exactly what’s in your home’s water and identify the right filtration solution for your family’s needs.
Common Water Contaminants Found in Northern Colorado
Water quality can vary by city, water source, plumbing age, and treatment method. Across Northern Colorado, water reports commonly identify:
| Water Contaminant | Common Source | Why Homeowners Care |
|---|---|---|
| Total Trihalomethanes (TTHMs) | Water disinfection process | Long-term exposure concerns |
| Haloacetic Acids (HAA5/HAA9) | Chlorination byproducts | Potential health concerns |
| Bromodichloromethane | Disinfection byproduct | Cancer-related concern in health guidelines |
| Chloroform | Disinfection byproduct | Long-term exposure concern |
| Chromium-6 | Natural deposits / industrial runoff | Emerging contaminant concern |
| Nitrates | Agriculture, runoff, natural sources | Drinking water concern |
| Chlorite | Water treatment byproduct | Blood chemistry concerns |
| Hard Water Minerals | Colorado geology | Scale buildup and appliance damage |
| Lead & Copper | Older plumbing systems | Plumbing and health concerns |
| PFAS “Forever Chemicals” | Industrial sources / environmental contamination | Emerging water contamination concern |
Fort Collins Water Contamination Concerns
The EWG Tap Water Database reports that the City of Fort Collins water system serves 179,901 people and uses surface water. EWG lists 23 total contaminants detected, with 10 contaminants exceeding EWG’s health guidelines.
Fort Collins contaminants reported by EWG include disinfection byproducts such as bromodichloromethane, chlorite, haloacetic acids, total trihalomethanes, and other detected contaminants.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0135291
Additional Fort Collins-related water system source:
https://www.ewg.org/tapwater/system.php?pws=CO0235185
Greeley Water Quality Concerns
The City of Greeley water system serves 112,816 people and uses surface water. EWG reports 25 total contaminants detected, with 9 contaminants exceeding EWG’s health guidelines.
Commonly reported Greeley water contaminants include disinfection byproducts, haloacetic acids, total trihalomethanes, nitrate, lithium, manganese, chromium-6, and other trace contaminants.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0162321
Evans Water Contamination Concerns
Evans homeowners may also be concerned about water contamination, hard water buildup, chlorine taste, and treatment byproducts. According to EWG, the City of Evans water system was in compliance with federal health-based drinking water standards for the latest EPA-assessed quarter, but that does not mean every homeowner’s water is free from contaminants or plumbing-related issues.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0162260
Windsor Water Quality Concerns
The Windsor water system uses purchased surface water and serves approximately 23,500 people. EWG reports 17 total contaminants detected, with 9 contaminants exceeding EWG’s health guidelines.
Windsor water testing data includes contaminants such as bromodichloromethane, haloacetic acids, total trihalomethanes, and other disinfection byproducts.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0162843
Wellington Water Quality Concerns
The Town of Wellington water system serves 13,884 people and uses groundwater. EWG reports 27 total contaminants detected, with 12 contaminants exceeding EWG’s health guidelines.
The Town of Wellington has 2 violations. Because violations and compliance status can change, homeowners in Wellington should pay close attention to current water quality reports and consider a water test if they are concerned about contamination.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0135838
Estes Park Water Quality Concerns
The Town of Estes Park water system serves 16,722 people and uses surface water. EWG reports 18 total contaminants detected, with 9 contaminants exceeding EWG’s health guidelines.
Reported contaminants include bromodichloromethane, haloacetic acids, disinfection byproducts, and other detected water contaminants.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0135257
Loveland Water Quality Concerns
The City of Loveland water system serves 76,378 people and uses surface water. EWG reports 23 total contaminants detected, with 10 contaminants exceeding EWG’s health guidelines.
Loveland water testing data includes haloacetic acids, total trihalomethanes, bromodichloromethane, and other treatment-related byproducts.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0135485
Longmont Water Quality Concerns
The City of Longmont water system serves 101,754 people and uses surface water. EWG reports 14 total contaminants detected, with 8 contaminants exceeding EWG’s health guidelines.
Longmont water reports include disinfection byproducts such as haloacetic acids and total trihalomethanes, along with other detected contaminants.
Source:
https://www.ewg.org/tapwater/system.php?pws=CO0107485
Johnstown & Ault Water Quality Concerns
Johnstown and Ault homeowners may also experience water quality issues such as hard water, chlorine taste, sediment, and plumbing-related contamination. EWG lists separate water systems for both communities.
Johnstown source:
https://www.ewg.org/tapwater/system.php?pws=CO0162418
Ault source:
https://www.ewg.org/tapwater/system.php?pws=CO0162125
Why Northern Colorado Homes Have Hard Water Problems
Hard water is one of the most common water quality complaints in Fort Collins, Greeley, Loveland, Windsor, Wellington, Evans, Longmont, Johnstown, Ault, and Estes Park.
Hard water contains minerals like calcium and magnesium that can build up inside plumbing systems and appliances.
Common signs of hard water include:
- White buildup on faucets and showerheads
- Water spots on dishes and glassware
- Dry skin and hair after showering
- Scale buildup inside water heaters
- Reduced appliance efficiency
- Cloudy or poor-tasting water
- Stiff laundry
- Shorter lifespan for fixtures and appliances
A water softener can help reduce hard water minerals and protect your plumbing system.
Signs Your Home May Need a Water Filtration System
You may need a whole-home water filtration system or reverse osmosis system if you notice:
- Chlorine in your tap water
- Bad tasting drinking water
- Cloudy water
- White residue on fixtures
- Sediment in your water
- Rust-colored water
- Dry skin after showering
- Water spots on dishes
- Scale buildup on appliances
- Concerns about PFAS, nitrates, chromium-6, or disinfection byproducts
A professional water test can help identify what is actually in your home’s water.
Best Water Filtration Systems for Northern Colorado Homes
Different homes need different water treatment solutions depending on the local water supply and the plumbing inside the home.
Whole-Home Water Filtration Systems
Whole-home filtration systems treat water as it enters your home, helping improve water quality at every faucet, shower, and appliance.
Reverse Osmosis Drinking Water Systems
Reverse osmosis systems are a popular option for drinking water because they help reduce many contaminants and improve taste.
Water Softeners
Water softeners help reduce hard water minerals that cause scale buildup, appliance damage, and dry skin.
Carbon Filtration Systems
Carbon filters can help reduce chlorine taste, odors, and many common chemical contaminants.
Sediment Filters
Sediment filters help capture dirt, rust, sand, and debris before they move through your plumbing system.
Get a Free Chlorine Water Test in Northern Colorado
Concerned about what is in your water? Schedule a free chlorine water test with Origin Plumbing Heating Cooling Electrical and find out what contaminants, minerals, and water quality issues may be affecting your home.
We proudly provide water filtration, water softener, and water treatment solutions in:
- Fort Collins
- Greeley
- Evans
- Windsor
- Wellington
- Estes Park
- Loveland
- Longmont
- Johnstown
- Ault
- Eaton
- Surrounding Northern Colorado communities
Whether you are worried about hard water, chlorine, PFAS, nitrates, sediment, chromium-6, or general water contamination, Origin Plumbing Heating Cooling Electrical can help you choose the right water filtration system for your home.
Cleaner water starts with knowing what is in it, schedule your free test today.