Is Mount Vernon, OR Tap Water Safe to Drink?
Graded B+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
83.5/100
waterverge.com Mount Vernon, OR — Water Quality Report
Mount Vernon's drinking water received a grade of B+ (83.5 out of 100), indicating good water quality. The city's 1 water system serves approximately 510 residents using groundwater.
Lead levels were measured at 1.3 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 93 violations on record, including 3 health-based violations. 7 remain unresolved.
What to know about Mount Vernon's water
Mount Vernon ranks #37 out of 213 cities in Oregon for water quality, placing it above average in the state.
Mount Vernon 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, Mount Vernon may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Mount Vernon, OR water safe to drink?
Mount Vernon's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 510 residents using groundwater (wells).
Recent water quality updates for Mount Vernon
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Mount Vernon's water quality assessment. Grade: B+ (83.5/100).
Contaminants: Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-4452). Flood event — may have impacted local water infrastructure.
Contaminants: Public Notice.
1 health-based. Contaminants: Coliform (TCR).
Federal disaster declaration (FEMA DR-3228). Coastal Storm event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Mount Vernon's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Mount Vernon's water system has 93 total violations on record, including 3 health-based violations. 7 remain unresolved. 1 violation was issued in the last 5 years.
Flood & environmental risk
Grant County has experienced 3 federally declared disasters since 1964. 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 Mount Vernon's water come from?
Mount Vernon's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 510 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Mount Vernon residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Mount Vernon'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.
Mount Vernon'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 droughtGrant 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
Grant County has experienced 3 federally declared disasters since 1964. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Mount Vernon's water supply, we recommend the following filter types.
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. | 1.3 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 1.40 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Mount Vernon compares by contaminant
Explore where Mount Vernon ranks among all Oregon cities for specific contaminants.
Water source & infrastructure
Where Mount Vernon's water comes from
Mount Vernon'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 510 people through 1 water system.
Water systems serving Mount Vernon
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MOUNT VERNON, CITY OF | OR4100546 | 510 | GW |
How Mount Vernon compares
Full Oregon rankings →Mount Vernon's score of 83.5/100 is above the average of 42/100 among major Oregon cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Oregon rankings →About Mount Vernon, OR
Wikipedia →Mount Vernon is a city in Grant County, Oregon, United States. Its post office was established in 1877 and named after a black stallion that belonged to settler David W. Jenkins. The stallion's stable, a small stone building, is still standing in a field on the north side of U.S. Highway 26 about 2.2 miles (3.5 km) east of the main intersection in town. In 1915 the ranching community had a population of 60 and a hotel at a hot springs resort approximately 2 miles (3.2 km) north. The population had grown to 451 by the 1950 census. There are a few motels and restaurants in Mount Vernon. As of the 2020 census, Mount Vernon had a population of 548.
Learn more about your water
Guides and resources related to Mount Vernon's water quality findings.
Explore water quality across Grant
Frequently asked questions
Is Mount Vernon, OR tap water safe to drink?
Mount Vernon's water quality earned a grade of B+ (83.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #37 out of 213 cities tested in Oregon.
What contaminants are in Mount Vernon's water?
Lead was measured at 1.3 ppb (90th percentile). 93 violations are on record.
How is Mount Vernon'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 Mount Vernon?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mount Vernon's water come from?
Mount Vernon's water is sourced from Groundwater. The city has 1 water system serving approximately 510 residents.
What health violations has Mount Vernon's water system had?
Mount Vernon has 3 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. 7 violations remain unresolved.
Is Mount Vernon's groundwater at risk of contamination?
Mount Vernon 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 93 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 Mount Vernon's water compare to other cities?
Mount Vernon ranks #37 out of 213 cities in Oregon (better than 83% of state cities) and #6426 out of 15744 cities nationally (59th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Mount Vernon's small water system affect quality?
Mount Vernon's system serves approximately 510 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 93 violations on record.