Water in Colorado.
Colorado utilities draw heavily from Front Range snowmelt watersheds. PFAS contamination from firefighting foam at Air Force bases and Colorado Springs is a major regional concern. Disinfection byproducts are widespread on river-fed systems.
Colorado Springs and Fountain saw some of the earliest documented PFAS exposure from military firefighting foam.
How Colorado regulates drinking water.
Federal SDWA primacy. State PFAS Action Plan launched 2020; CDPHE has its own PFAS testing program. No state MCLs stricter than federal.
Colorado Department of Public Health and Environment — Water Quality Control Division
Colorado's water history, in order.
The contamination events, regulatory shifts, and major settlements that define how this state thinks about drinking water today.
- 2016
PFAS contamination from Peterson AFB firefighting foam confirmed in Fountain/Widefield/Security.
- 2018
Colorado Springs sues 3M and Tyco over PFAS contamination.
- 2020
Colorado PFAS Action Plan launched with statewide sampling.
- 2024
Federal PFAS rule formally regulates six PFAS compounds.
The actual water you drink.
The physical rivers, aquifers, lakes, and reservoirs that feed Colorado's public water systems. Source quality is the foundation of tap quality — and where the long-term protection fights happen.
- riverColorado River (West Slope)
Major raw-water source for Front Range via transbasin diversions.
- riverSouth Platte River
Denver metro.
- riverArkansas River
Colorado Springs / Pueblo.
- riverCache la Poudre
Fort Collins / Greeley.
- aquiferDenver Basin Aquifer System
Front Range groundwater (heavily managed).
Source-water mix
~70% snowmelt surface water, ~30% groundwater
Major cities served
Denver · Colorado Springs · Aurora · Fort Collins · Boulder
Who actually serves the water.
The largest public water systems in Colorado by population served. Click your ZIP after to see the full live EWG report for your specific utility.
- Denver WaterDenver metro1,500Kserved
- Aurora WaterAurora400Kserved
- Colorado Springs UtilitiesColorado Springs480Kserved
- Fort Collins UtilitiesFort Collins175Kserved
Where the contamination comes from.
Every state has a different industrial fingerprint. The industries below are the dominant historical and active contamination sources in Colorado's drinking water systems.
Peterson Space Force Base and other military bases drove PFAS contamination in the El Paso County corridor (Fountain, Widefield, Security). Oil and gas operations on the Front Range produce produced-water and air-quality concerns. Legacy mining (Leadville, Idaho Springs) drives ongoing heavy-metal Superfund work.
What state data flags most consistently.
Drawn from EPA SDWIS sampling records, EWG state summaries, and regional regulatory action over the past five years. Read the full deep dive on each.
PFAS (Forever Chemicals)
A class of ~15,000 synthetic chemicals that don't break down. Now regulated for the first time.
Trihalomethanes (TTHMs)
Byproducts of chlorinating water. Linked to bladder cancer at chronic exposure.
Chromium-6 (Hexavalent Chromium)
The Erin Brockovich chemical. A known carcinogen with no federal-specific limit yet.
Lead
A neurotoxic metal that leaches from old pipes and solder. No safe level for children.
Risk isn't evenly distributed.
Residents in El Paso County (Colorado Springs / Fountain / Widefield / Security) face the most-documented PFAS exposure from military firefighting foam.
~10% of households on private wells, mostly mountain and Eastern Plains.
What's coming for Colorado's water.
Snowpack decline reshapes Front Range supply; Colorado River basin shortage cascades downstream. Wildfire burn-scar sediment events damaged Cameron Peak / East Troublesome watersheds. Earlier spring runoff stresses reservoir management.
Limited program
CDPHE provides voluntary technical and lab assistance. No statewide mandate. Several Front Range districts have voluntarily tested.
Five questions for your next Consumer Confidence Report.
Your utility is required to send you a Consumer Confidence Report annually. Most are dense and procedural. These are the questions worth following up on for Colorado specifically.
- 1
Does my system source any water through the Colorado-Big Thompson or Fryingpan-Arkansas projects?
- 2
If I live in El Paso County, is my system part of the PFAS-contaminated zone?
- 3
What is my utility's lead and copper rule compliance status?
- 4
Are there any active oil/gas pad concerns near my source water?
Most state regulators allow public records requests for the underlying lab reports behind your CCR — your utility should be able to provide them on request.
What's changed in Colorado water law.
Drinking water regulation moves at the state level as much as the federal level. Below are notable recent bills and regulatory actions specific to Colorado.
- 2022
HB22-1345 — Restrictions on PFAS in consumer products (firefighting foam, cosmetics, food packaging).
- 2020
Colorado PFAS Action Plan launched.
For PFAS removal, NSF/ANSI P473 carbon or reverse osmosis. Pitcher filters labeled "PFOA reduction" using activated carbon work for many compounds.
We don't recommend brands — the NSF/ANSI certification number matters more than the name on the box.
This is the state. Your address is the answer.
State-level patterns don't tell you about your specific tap. Run your ZIP for the live EWG contaminant report on your utility — or build a personalized Water File for your household.
Source-water mix, utility counts, lead-service-line estimates, and private-well shares are approximate, drawn from EPA SDWIS public data and state primacy-agency summaries. Contaminant rankings reflect EWG state-level monitoring data and regional regulatory action — they are not exhaustive. Timeline events are publicly documented. See methodology for the full sourcing. Search EPA SDWIS for Colorado