Is Mammoth Spring, AR Tap Water Safe to Drink?
Graded F, with 123 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
44/100
waterverge.com Mammoth Spring, AR — Water Quality Report
Mammoth Spring's drinking water received a grade of F (44 out of 100), indicating failing water quality. The city's 2 water systems serve approximately 1,829 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 245 violations on record, including 72 health-based violations. 123 remain unresolved.
What to know about Mammoth Spring's water
Mammoth Spring ranks #330 out of 345 cities in Arkansas for water quality, placing it among the lowest-rated in the state.
Mammoth Spring 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, Mammoth Spring may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 145 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Mammoth Spring, AR water safe to drink?
Mammoth Spring's drinking water has significant quality concerns based on EPA testing data. With a grade of F (44/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,829 residents using groundwater (wells).
Recent water quality updates for Mammoth Spring
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Mammoth Spring's water quality assessment. Grade: F (44/100).
1 health-based. Contaminants: Revised Total Coliform Rule, Stage 1 Disinfectants and Disinfection Byproducts Rule, Public Notice.
1 health-based. Contaminants: Stage 1 Disinfectants and Disinfection Byproducts Rule, Revised Total Coliform Rule, Groundwater Rule.
1 health-based. Contaminants: Revised Total Coliform Rule, Stage 1 Disinfectants and Disinfection Byproducts Rule, Groundwater Rule.
Federal disaster declaration (FEMA DR-4873). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3541). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Mammoth Spring's water supply.
Well within EPA limits.
Violation history
Mammoth Spring's water system has 245 total violations on record, including 72 health-based violations. 123 remain unresolved. 145 violations were issued in the last 5 years.
Flood & environmental risk
Fulton 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. Local water sources include Mammoth Spring At Mammoth Spring, Spring River Near Mammoth Spring, South Fork Spring River At Saddle.
Where does Mammoth Spring's water come from?
Mammoth Spring's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,829 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Mammoth Spring At Mammoth Spring (spring), Spring River Near Mammoth Spring (river), South Fork Spring River At Saddle (river).
What Mammoth Spring residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Mammoth Spring'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.
Mammoth Spring'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
D4 — exceptional droughtFulton County is currently in D4 (exceptional drought) per the U.S. Drought Monitor (week of May 5, 2026). 9.4% of the county is in D4 (exceptional) drought. 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
Fulton 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. | 2.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Mammoth Spring compares by contaminant
Explore where Mammoth Spring ranks among all Arkansas cities for specific contaminants.
Water source & infrastructure
Where Mammoth Spring's water comes from
Mammoth Spring'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 1,829 people through 2 water systems.
Water bodies near Mammoth Spring
Mammoth Spring is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Mammoth Spring
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MAMMOTH SPRING WATERWORKS | AR0000206 | 1,777 | GW |
| HOSANNA HEIGHTS WATER | AR0000884 | 52 | GW |
How Mammoth Spring compares
Full Arkansas rankings →Mammoth Spring's score of 44/100 is below the average of 75/100 among major Arkansas cities. 10 of 10 nearby cities score higher.
Nearby cities
View Arkansas rankings →About Mammoth Spring, AR
Wikipedia →Mammoth Spring is a city in Fulton County, Arkansas. The population was 929 at the time of the 2020 census and is home to Mammoth Spring, one of the largest natural springs in the world. The location is renowned for its trout fishing.
Learn more about your water
Guides and resources related to Mammoth Spring's water quality findings.
Explore water quality across Fulton
Frequently asked questions
Is Mammoth Spring, AR tap water safe to drink?
Mammoth Spring's water quality earned a grade of F (44/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #330 out of 345 cities tested in Arkansas.
What contaminants are in Mammoth Spring's water?
Lead was measured at 2.0 ppb (90th percentile). 245 violations are on record.
How is Mammoth Spring'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 Mammoth Spring?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mammoth Spring's water come from?
Mammoth Spring's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,829 residents.
What health violations has Mammoth Spring's water system had?
Mammoth Spring has 72 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. 123 violations remain unresolved.
Is Mammoth Spring's groundwater at risk of contamination?
Mammoth Spring 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 245 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 Mammoth Spring's water compare to other cities?
Mammoth Spring ranks #330 out of 345 cities in Arkansas (better than 4% of state cities) and #14480 out of 15744 cities nationally (8th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.