Is Otis, CO Tap Water Safe to Drink?
Graded C+, with 23 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
69.9/100
waterverge.com Otis, CO — Water Quality Report
Otis's drinking water received a grade of C+ (69.9 out of 100), indicating fair water quality. The city's 1 water system serves approximately 600 residents using groundwater.
Lead levels were measured at 0.0 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 180 violations on record, including 2 health-based violations. 23 remain unresolved.
What to know about Otis's water
Otis ranks #122 out of 246 cities in Colorado for water quality, placing it mid-range in the state.
Otis 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, Otis may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 13 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Otis, CO water safe to drink?
Otis's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (69.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 600 residents using groundwater (wells).
Recent water quality updates for Otis
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Otis's water quality assessment. Grade: C+ (69.9/100).
Contaminants: LEAD AND COPPER RULE REVISIONS.
Contaminants: Lead and Copper Rule.
Federal disaster declaration (FEMA DR-4731). Flood event — may have impacted local water infrastructure.
Contaminants: Public Notice.
Federal disaster declaration (FEMA DR-4229). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Otis's water supply.
Well within EPA limits.
Violation history
Otis's water system has 180 total violations on record, including 2 health-based violations. 23 remain unresolved. 13 violations were issued in the last 5 years.
Flood & environmental risk
Washington County has experienced 7 federally declared disasters since 1969. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.
Where does Otis's water come from?
Otis's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 600 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Otis residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Otis'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.
Otis'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
D3 — extreme droughtWashington 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
Washington County has experienced 7 federally declared disasters since 1969. 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. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Otis compares by contaminant
Explore where Otis ranks among all Colorado cities for specific contaminants.
Water source & infrastructure
Where Otis's water comes from
Otis'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 600 people through 1 water system.
Water systems serving Otis
| System Name | PWSID | Population | Source |
|---|---|---|---|
| OTIS TOWN OF | CO0161010 | 600 | GW |
How Otis compares
Full Colorado rankings →Otis's score of 69.9/100 is above the average of 45/100 among major Colorado cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Colorado rankings →About Otis, CO
Wikipedia →Otis is a Statutory Town in Washington County, Colorado, United States. The population was 511 at the 2020 census.
Learn more about your water
Guides and resources related to Otis's water quality findings.
Explore water quality across Washington
Frequently asked questions
Is Otis, CO tap water safe to drink?
Otis's water quality earned a grade of C+ (69.9/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #122 out of 246 cities tested in Colorado.
What contaminants are in Otis's water?
Lead was measured at 0.0 ppb (90th percentile). 180 violations are on record.
How is Otis'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 Otis?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Otis's water come from?
Otis's water is sourced from Groundwater. The city has 1 water system serving approximately 600 residents.
What health violations has Otis's water system had?
Otis has 2 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 23 violations remain unresolved.
Is Otis's groundwater at risk of contamination?
Otis 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 180 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 Otis's water compare to other cities?
Otis ranks #122 out of 246 cities in Colorado (better than 50% of state cities) and #10841 out of 15744 cities nationally (31th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Otis's small water system affect quality?
Otis's system serves approximately 600 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 180 violations on record.