Is El Dorado Waterworks Tap Water Safe? Quality Report

Water source: Ground water
Ownership: Local government
Counties served: Union

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

health-based violations

violations on file

still open

Violation	Type	Status	Period
MCL	Health-based	Archived	2025-10-01 → 2025-12-31
MCL	Health-based	Archived	2025-10-01 → 2025-12-31
MCL	Health-based	Archived	2025-07-01 → 2025-09-30
MCL	Health-based	Archived	2025-07-01 → 2025-09-30
MCL	Health-based	Archived	2025-07-01 → 2025-09-30
MCL	Health-based	Resolved	2021-01-01 → 2021-03-31
MCL	Health-based	Resolved	2021-01-01 → 2021-03-31
MCL	Health-based	Resolved	2020-10-01 → 2020-12-31
MCL	Health-based	Resolved	2020-10-01 → 2020-12-31
MCL	Health-based	Resolved	2020-10-01 → 2020-12-31

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.

Contaminant	Level vs EPA limit	Detection rate	Source	Period
Dibromochloromethane	17.645 µg/L No EPA limit set worst single sample: 27.8 µg/L	198/205	SYR4	2012–2019
Fluoride	1012.5 µg/L 25% of the EPA limit 4000 µg/L worst single sample: 1110 µg/L	196/196	SYR4	2012–2019
Bromoform	60.49 µg/L No EPA limit set worst single sample: 77.5 µg/L	135/138	SYR4	2012–2019
Bromodichloromethane	6.1 µg/L No EPA limit set worst single sample: 9.4 µg/L	129/138	SYR4	2012–2019
TTHM	83.55 µg/L 104% of the EPA limit, at the 95th percentile of samples — 80 µg/L worst single sample: 99.6 µg/L	126/128	SYR4	2012–2019
Dibromoacetic Acid	10.095 µg/L No EPA limit set worst single sample: 11.7 µg/L	122/126	SYR4	2012–2019
Total Haloacetic Acids (HAA5)	12.56 µg/L 21% of the EPA limit 60 µg/L worst single sample: 18.7 µg/L	122/126	SYR4	2012–2019
Chloroform	2.5 µg/L No EPA limit set worst single sample: 3.5 µg/L	101/138	SYR4	2012–2019
Copper	706 µg/L 54% of the EPA limit 1300 µg/L worst single sample: 980 µg/L	73/90	SYR4	2013–2019
Lead	9 µg/L 60% of the EPA limit 15 µg/L worst single sample: 18 µg/L	71/96	SYR4	2012–2019
Dichloroacetic Acid	2.36 µg/L No EPA limit set worst single sample: 3.7 µg/L	49/126	SYR4	2012–2019
Trichloroacetic Acid	1.5 µg/L No EPA limit set worst single sample: 2.1 µg/L	40/126	SYR4	2012–2019
Lead	0.0020 mg/L 13% of the EPA limit 0.0150 mg/L	15/15	LCR	2025
Monobromoacetic Acid	1.81 µg/L No EPA limit set worst single sample: 2.3 µg/L	15/126	SYR4	2012–2019
Lithium	11.2 µg/L No EPA limit set	4/4	UCMR-5	2023
Nitrate-Nitrite	100 µg/L 1% of the EPA limit 10000 µg/L	2/34	SYR4	2012–2019

91 contaminants tested, none detected

1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalArsenicAtrazineBhc-GammaBariumBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateGross Beta Particle ActivityHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonochloroacetic AcidNetfosaaNfdhaNmefosaaOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: MCMAHAN, MICHAEL
Phone: 870-862-1912

Frequently asked questions about El Dorado Waterworks

Is El Dorado Waterworks tap water safe to drink?

EPA monitoring detected 16 contaminants in El Dorado Waterworks's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in El Dorado Waterworks's water?

EPA monitoring detected Dibromochloromethane, Fluoride, Bromoform, Bromodichloromethane, TTHM, and others. The full list with the level and data source for each is above.

How many people does El Dorado Waterworks serve?

El Dorado Waterworks reports serving 17,932 people in Arkansas, per its EPA record.

Has El Dorado Waterworks had any water quality violations?

The EPA has 45 violations on file for El Dorado Waterworks, of which 44 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.