Is Holly, CO Tap Water Safe to Drink?
Graded D+, with 36 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
50/100
waterverge.com Holly, CO — Water Quality Report
Holly's drinking water received a grade of D+ (50 out of 100), indicating poor water quality. The city's 3 water systems serve approximately 1,226 residents using groundwater.
Lead levels were measured at 1.0 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 244 violations on record, including 60 health-based violations. 36 remain unresolved.
What to know about Holly's water
Holly ranks #164 out of 246 cities in Colorado for water quality, placing it below average in the state.
Holly 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, Holly may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 62 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Holly, CO water safe to drink?
Holly's drinking water has significant quality concerns based on EPA testing data. With a grade of D+ (50/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 1,226 residents using groundwater (wells).
Recent water quality updates for Holly
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Holly's water quality assessment. Grade: D+ (50/100).
Contaminants: Revised Total Coliform Rule.
2 health-based. Contaminants: Public Notice, Combined Radium (-226 and -228), Chlorine.
2 health-based. Contaminants: Consumer Confidence Rule, 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 Holly's water supply.
Well within EPA limits.
Violation history
Holly's water system has 244 total violations on record, including 60 health-based violations. 36 remain unresolved. 62 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 Wild Horse Creek Above Holly, Arkansas River, Frontier Ditch Nr Coolidge, Arkansas R Nr Coolidge.
Where does Holly's water come from?
Holly's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 1,226 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Wild Horse Creek Above Holly (river), Arkansas River (river), Frontier Ditch Nr Coolidge (stream), Arkansas R Nr Coolidge (river).
What Holly residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Holly'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.
Holly'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
Drought conditions
D2 — severe droughtCheyenne County is currently in D2 (severe 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. | 1.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Holly compares by contaminant
Explore where Holly ranks among all Colorado cities for specific contaminants.
Water source & infrastructure
Where Holly's water comes from
Holly'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 local government ownership and serves approximately 1,226 people through 3 water systems.
Water bodies near Holly
Holly is located near 4 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Holly
| System Name | PWSID | Population | Source |
|---|---|---|---|
| HOLLY TOWN OF | CO0150600 | 800 | GW |
| KIT CARSON TOWN OF | CO0109011 | 326 | GW |
| A AND B WA INC | CO0150100 | 100 | GW |
How Holly compares
Full Colorado rankings →Holly's score of 50/100 is on par with the average of 45/100 among major Colorado cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Colorado rankings →About Holly, CO
Wikipedia →Holly is a statutory town in Prowers County in southeastern Colorado, United States. The town is located 4.3 miles (6.9 km) west of the Kansas border at an elevation of 3,393 feet (1,034 m). Despite having the lowest elevation of any Colorado municipality, Holly is higher than the high points of 19 states and the District of Columbia. The town population was 837 at the 2020 United States census.
Learn more about your water
Guides and resources related to Holly's water quality findings.
Explore water quality across Prowers
Frequently asked questions
Is Holly, CO tap water safe to drink?
Holly's water quality earned a grade of D+ (50/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #164 out of 246 cities tested in Colorado.
What contaminants are in Holly's water?
Lead was measured at 1.0 ppb (90th percentile). 244 violations are on record.
How is Holly'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 Holly?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Holly's water come from?
Holly's water is sourced from Groundwater. The city has 3 water systems serving approximately 1,226 residents.
What health violations has Holly's water system had?
Holly has 60 health-based violations on record. The most recent violation was recorded in November 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 36 violations remain unresolved.
Is Holly's groundwater at risk of contamination?
Holly 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 244 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 Holly's water compare to other cities?
Holly ranks #164 out of 246 cities in Colorado (better than 33% of state cities) and #13155 out of 15744 cities nationally (16th percentile). The grade of D+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.