Is Wiley, CO Tap Water Safe to Drink?
Graded D+, with 11 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
52/100
waterverge.com Wiley, CO — Water Quality Report
Wiley's drinking water received a grade of D+ (52 out of 100), indicating poor water quality. The city's 2 water systems serve approximately 1,905 residents using groundwater.
Lead levels were measured at 2.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 627 violations on record, including 376 health-based violations. 11 remain unresolved.
What to know about Wiley's water
Wiley ranks #157 out of 246 cities in Colorado for water quality, placing it below average in the state.
Wiley relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Wiley may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 216 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Wiley, CO water safe to drink?
Wiley's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (52/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,905 residents using groundwater (wells).
Recent water quality updates for Wiley
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Wiley's water quality assessment. Grade: D+ (52/100).
9 health-based. Contaminants: Gross Alpha, Excl. Radon and U, Combined Radium (-226 and -228).
9 health-based. Contaminants: Gross Alpha, Excl. Radon and U, Combined Radium (-226 and -228).
10 health-based. Contaminants: Gross Alpha, Excl. Radon and U, Combined Radium (-226 and -228).
Federal disaster declaration (FEMA DR-4731). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3224). Coastal Storm event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Wiley's water supply.
Well within EPA limits.
Violation history
Wiley's water system has 627 total violations on record, including 376 health-based violations. 11 remain unresolved. 216 violations were issued in the last 5 years.
Flood & environmental risk
Prowers County has experienced 3 federally declared disasters since 1997. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Arkansas River.
Where does Wiley's water come from?
Wiley's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,905 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Arkansas River (river).
What Wiley residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Wiley's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Wiley's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Wiley
Industrial polluters nearby
Reported releases to surface water by facilities near Wiley, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
CF MAIER COMPOSITES INC. LAMAR, CO81052 | — | — | 6.9 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Drought conditions
D3 — extreme droughtProwers County is currently in D3 (extreme drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Prowers County has experienced 3 federally declared disasters since 1997. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 2.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Wiley compares by contaminant
Explore where Wiley ranks among all Colorado cities for specific contaminants.
Water source & infrastructure
Where Wiley's water comes from
Wiley's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by private ownership and serves approximately 1,905 people through 2 water systems.
Water bodies near Wiley
Wiley is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Wiley
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MAY VALLEY WA | CO0150800 | 1,500 | GW |
| WILEY TOWN OF | CO0150900 | 405 | GW |
How Wiley compares
Full Colorado rankings →Wiley's score of 52/100 is above the average of 45/100 among major Colorado cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Colorado rankings →About Wiley, CO
Wikipedia →Wiley is a statutory town in Prowers County, Colorado, United States. The population was 437 at the 2020 Census.
Learn more about your water
Guides and resources related to Wiley's water quality findings.
Explore water quality across Prowers
Frequently asked questions
Is Wiley, CO tap water safe to drink?
Wiley's water quality earned a grade of D+ (52/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #157 out of 246 cities tested in Colorado.
What contaminants are in Wiley's water?
Lead was measured at 2.0 ppb (90th percentile). 627 violations are on record.
How is Wiley's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Wiley?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Wiley's water come from?
Wiley's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,905 residents.
What health violations has Wiley's water system had?
Wiley has 376 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 11 violations remain unresolved.
Is Wiley's groundwater at risk of contamination?
Wiley uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 627 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Wiley's water compare to other cities?
Wiley ranks #157 out of 246 cities in Colorado (better than 36% of state cities) and #12812 out of 15744 cities nationally (19th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.