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Tap water quality report

Oaks Water Users Association

EPA monitoring tested this supplier for 21 contaminants and detected 7. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

21
contaminants tested
7
detected
180
people served
8
health-based violations
South Dakota rankingsLead in South DakotaPFAS in South Dakota
Water source
Ground water
Ownership
Private
Counties served
Pennington

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.

8
health-based violations
166
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2015-02-01
TT Health-based Resolved 2015-02-01
MCL Health-based Resolved 1999-02-01 → 1999-02-28
MCL Health-based Resolved 1999-02-01 → 1999-02-28
MCL Health-based Resolved 1999-02-01 → 1999-02-28
MCL Health-based Resolved 1996-10-01 → 1996-10-31
MCL Health-based Resolved 1996-10-01 → 1996-10-31
MCL Health-based Resolved 1996-10-01 → 1996-10-31
MR Monitoring Resolved 2001-07-01 → 2001-09-30
MR Monitoring Resolved 2001-07-01 → 2001-09-30

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 single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Copper
254 µg/L 20%
of the EPA limit 1300 µg/L
 15/15 SYR4 2013–2019
Lead
0.0020 mg/L 13%
of the EPA limit 0.0150 mg/L
 15/15 LCR 2025
Lead
1 µg/L 6.7%
of the EPA limit 15 µg/L
 15/15 SYR4 2013–2019
Barium
54 µg/L 2.7%
of the EPA limit 2000 µg/L
 1/1 SYR4 2014
Chromium
1 µg/L 1%
of the EPA limit 100 µg/L
 1/1 SYR4 2014
Fluoride
400 µg/L 10%
of the EPA limit 4000 µg/L
 1/1 SYR4 2014
Gross Alpha, Excl. Radon And U
7.14 pCi/L 48%
of the EPA limit 15 pCi/L
 1/1 SYR4 2019
14 contaminants tested, none detected
Antimony, TotalArsenicBeryllium, TotalCadmiumCombined Radium (-226 And -228)Combined UraniumGross Beta Particle ActivityMercuryNitrateNitriteSeleniumTTHMThallium, TotalTotal Haloacetic Acids (HAA5)

Utility contact

Contact
ANDREW JOHNSON
Email
abj1976@gmail.com

Frequently asked questions about Oaks Water Users Association

Is Oaks Water Users Association tap water safe to drink?

EPA monitoring detected 7 contaminants in Oaks Water Users Association'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 Oaks Water Users Association's water?

EPA monitoring detected Copper, Lead, Lead, Barium, Chromium, and others. The full list with the level and data source for each is above.

How many people does Oaks Water Users Association serve?

Oaks Water Users Association reports serving 180 people in South Dakota, per its EPA record.

Has Oaks Water Users Association had any water quality violations?

The EPA has 166 violations on file for Oaks Water Users Association, of which 8 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.