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Well Water in Arkansas

Contaminant risks, testing requirements, and treatment recommendations for private well owners in Arkansas.

Arkansas Geology and Groundwater

Arkansas sits on Ozark Plateau karst and Coastal Plain sediments. This geology directly determines what contaminants are likely in private well water. Moderate risk exists for nitrate.

Contaminant Risk Profile

ContaminantRisk LevelWhy
ArsenicLow riskGenerally low in this region's geology.
NitrateModerate riskSome areas near farmland or septic systems may have elevated levels.
RadonLow riskNot a primary concern in most of this state.
PFASLow riskFewer known contamination sources, but PFAS can travel far through groundwater.
Iron/ManganeseModerate riskFound in some wells depending on local geology.

How Arkansas Compares: Municipal Water Data

CheckMyTap tracks water quality for 13 cities in Arkansas. While these numbers reflect municipal water (not private wells), they indicate the baseline mineral content of Arkansas's water sources. Private wells often draw from the same aquifers but with less treatment.

MetricArkansas AverageNational Average
Hardness51 PPM (soft)170 PPM
Hardness range22 - 98 PPM25 - 400+ PPM
Lead (avg municipal)1 ppb3.2 ppb
Nitrate (avg municipal)0.7 mg/L1.1 mg/L
Cities with PFAS detected1 of 13~45% nationally
Cities exceeding PFAS MCL (4 ppt)1

Hardest water in Arkansas: Fayetteville (98 PPM), Benton (90 PPM), Rogers (85 PPM), Bentonville (80 PPM), Springdale (64 PPM).

Softest water: Pine Bluff (22 PPM), Little Rock (24 PPM), North Little Rock (25 PPM).

Testing Requirements in Arkansas

Arkansas does not have a statewide mandatory testing requirement for existing private wells. Regardless of state requirements, the EPA recommends testing annually for:

  • Every year: Total coliform bacteria, E. coli, nitrate, pH, and total dissolved solids
  • At least once: Arsenic, lead, copper, fluoride, and any contaminant identified as a local risk
  • After events: Retest after flooding, well repairs, nearby construction, or any change in taste/color/odor

Recommended Treatment for Arkansas Wells

Based on Arkansas's geology and common contaminant risks, these treatment systems address the most likely issues:

UV Disinfection

Kills bacteria and viruses without chemicals. Recommended for all well water systems

Already have your lab results? Use our free well water interpreter to find out what your numbers mean. Interpret your well water lab report

Frequently Asked Questions

Is well water in Arkansas safe to drink?

Well water quality in Arkansas varies significantly by location and geology. Arkansas sits on Ozark Plateau karst and Coastal Plain sediments. No single contaminant dominates statewide, but local conditions vary. The only way to know your specific water quality is to test it. Use our free interpreter to understand your results.

How often should I test my well water in Arkansas?

The EPA recommends testing annually for bacteria (total coliform, E. coli), nitrate, total dissolved solids, and pH. Test more frequently if you notice changes in taste, color, or odor, or after flooding, nearby construction, or well repairs.

Does Arkansas require well water testing?

Arkansas does not have a statewide mandatory testing requirement for existing private wells. However, the EPA strongly recommends annual testing regardless of state requirements. Your county health department may have additional local requirements.

What is the average water hardness in Arkansas?

Municipal water in Arkansas averages 51 PPM across 13 cities tracked by CheckMyTap, ranging from 22 to 98 PPM. Private well water typically runs 20-50% harder than city water because groundwater has more contact time with mineral formations. Many Arkansas well owners have manageable hardness levels, though local variation is significant. Check your city's data.

View All 13 Arkansas City Reports