Is Tarkio, MO Tap Water Safe to Drink?
Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
92.8/100
waterverge.com Tarkio, MO — Water Quality Report
Tarkio's drinking water received a grade of A (92.8 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,494 residents using purchased ground water.
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 29 violations on record, including 5 health-based violations. 2 remain unresolved.
What to know about Tarkio's water
Tarkio ranks #40 out of 509 cities in Missouri for water quality, placing it one of the best in the state.
Tarkio purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
As a small community water system, Tarkio may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Tarkio, MO water safe to drink?
Tarkio's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (92.8/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 1,494 residents using groundwater (wells).
Recent water quality updates for Tarkio
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Tarkio's water quality assessment. Grade: A (92.8/100).
Federal disaster declaration (FEMA DR-4435). Flood event — may have impacted local water infrastructure.
1 health-based. Contaminants: TTHM.
1 health-based. Contaminants: TTHM.
Contaminants: Public Notice.
Federal disaster declaration (FEMA DR-4012). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Tarkio's water supply.
Well within EPA limits.
Violation history
Tarkio's water system has 29 total violations on record, including 5 health-based violations. 2 remain unresolved.
Flood & environmental risk
Atchison County has experienced 9 federally declared disasters since 1965. 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 Tarkio River At Fairfax.
Where does Tarkio's water come from?
Tarkio's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,494 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Tarkio River At Fairfax (river).
What Tarkio residents can do
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.
Tarkio'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
Flood & disaster history
Atchison County has experienced 9 federally declared disasters since 1965. 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 Tarkio compares by contaminant
Explore where Tarkio ranks among all Missouri cities for specific contaminants.
Water source & infrastructure
Where Tarkio's water comes from
Tarkio purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Tarkio's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by local government ownership and serves approximately 1,494 people through 1 water system.
Water bodies near Tarkio
Tarkio is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Tarkio
| System Name | PWSID | Population | Source |
|---|---|---|---|
| TARKIO BOARD OF PUBLIC WORKS PWS | MO1010786 | 1,494 | GWP |
How Tarkio compares
Full Missouri rankings →Tarkio's score of 92.8/100 is above the average of 62/100 among major Missouri cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Missouri rankings →About Tarkio, MO
Learn more about your water
Guides and resources related to Tarkio's water quality findings.
Explore water quality across Atchison
Frequently asked questions
Is Tarkio, MO tap water safe to drink?
Tarkio's water quality earned a grade of A (92.8/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #40 out of 509 cities tested in Missouri.
What contaminants are in Tarkio's water?
Lead was measured at 0.0 ppb (90th percentile). 29 violations are on record.
How is Tarkio'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 Tarkio?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Tarkio's water come from?
Tarkio's water is sourced from Purchased ground water. The city has 1 water system serving approximately 1,494 residents.
What health violations has Tarkio's water system had?
Tarkio has 5 health-based violations on record. The most recent violation was recorded in January 2013. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.
Is Tarkio's groundwater at risk of contamination?
Tarkio 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 29 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 Tarkio's water compare to other cities?
Tarkio ranks #40 out of 509 cities in Missouri (better than 92% of state cities) and #1112 out of 15744 cities nationally (93th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Tarkio's small water system affect quality?
Tarkio's system serves approximately 1,494 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 29 violations on record.