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Community Water System · PWS SD4602185

Clay RWS/South Union

Wakonda, South Dakota 57073 - drinking water served from groundwater sources to 1,447 people, tracked in EPA SDWIS and UCMR5.

1,447
People served
331
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 331 drinking-water violations at Clay RWS/South Union - above the South Dakota per-system average.

331
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
1,447
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Clay RWS/South Union

Clay RWS/South Union is a private-owned community water system that delivers drinking water to 1,447 residents in Wakonda, South Dakota (Union County) through 579 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 331 total violations for this system , of which 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 329 monitoring and reporting violations are on file. The most recent violation on record dates to 2004.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 7 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across South Dakota, EPA tracks 654 public water systems serving 915,901 people, with 56,254 cumulative violations and 8,399 health-based violations on record. About 92% of systems in the state carry at least one violation, and state-wide the average per system is 86 violations. Statewide, 42 of 49 UCMR5-tested systems have reported PFAS detections (85.7%).

Clay RWS/South Union's 331 violations sit above the South Dakota average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
1,447
Total Violations
331
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
579
County
Union
School/Daycare
No
MCL Violations
0
Monitoring Violations
329
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 7 2000
Lead and Copper Rule MR 7 2000
LASSO MR 6 2004
Heptachlor MR 6 2004
Benzo(a)pyrene MR 6 2004
Methoxychlor MR 6 2004
Di(2-ethylhexyl) adipate MR 6 2004
Di(2-ethylhexyl) phthalate MR 6 2004
Hexachlorocyclopentadiene MR 6 2004
Endrin MR 6 2004
HEXACHLOROBENZENE MR 6 2004
Toxaphene MR 6 2004
Simazine MR 6 2004
OXAMYL MR 6 2004
2,4,5-TP MR 6 2004
Pentachlorophenol MR 6 2004
1,2-DIBROMO-3-CHLOROPROPANE MR 6 2004
ETHYLENE DIBROMIDE MR 6 2004
Endothall MR 6 2004
Glyphosate MR 6 2004
Heptachlor epoxide MR 6 2004
Atrazine MR 6 2004
Chlordane MR 6 2004
Carbofuran MR 6 2004
Diquat MR 6 2004
BHC-GAMMA MR 6 2004
Dalapon MR 6 2004
2,4-D MR 6 2004
Dinoseb MR 6 2004
Picloram MR 6 2004

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Clay RWS/South Union.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID SD4602185 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

South Dakota Drinking Water Authority

South Dakota's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find SD regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2004 LASSO MR 6 SDWIS / SD4602185 / 2051
2004 Heptachlor MR 6 SDWIS / SD4602185 / 2065
2004 Benzo(a)pyrene MR 6 SDWIS / SD4602185 / 2306
2004 Methoxychlor MR 6 SDWIS / SD4602185 / 2015
2004 Di(2-ethylhexyl) adipate MR 6 SDWIS / SD4602185 / 2035
2004 Di(2-ethylhexyl) phthalate MR 6 SDWIS / SD4602185 / 2039
2004 Hexachlorocyclopentadiene MR 6 SDWIS / SD4602185 / 2042
2004 Endrin MR 6 SDWIS / SD4602185 / 2005
2004 HEXACHLOROBENZENE MR 6 SDWIS / SD4602185 / 2274
2004 Toxaphene MR 6 SDWIS / SD4602185 / 2020
2004 Simazine MR 6 SDWIS / SD4602185 / 2037
2004 OXAMYL MR 6 SDWIS / SD4602185 / 2036
2004 2,4,5-TP MR 6 SDWIS / SD4602185 / 2110
2004 Pentachlorophenol MR 6 SDWIS / SD4602185 / 2326
2004 1,2-DIBROMO-3-CHLOROPROPANE MR 6 SDWIS / SD4602185 / 2931

How Clay RWS/South Union Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Clay RWS/South Union South Dakota avg Federal benchmark
Total violations 331 86 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 12.8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 85.7% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 1,447 1,400 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 654 regulated public water systems in South Dakota.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Clay RWS/South Union water safe to drink? ▼
Clay RWS/South Union (PWS ID: SD4602185) has 331 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 1,447 people using Groundwater sources.
How many people does Clay RWS/South Union serve? ▼
Clay RWS/South Union serves 1,447 people in Wakonda, South Dakota. It is a Private-owned system using Groundwater water sources with 579 service connections.
What type of violations does Clay RWS/South Union have? ▼
Clay RWS/South Union has 331 total violations: 0 health-based violations (MCL exceedances or treatment failures), 329 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Clay RWS/South Union water? ▼
No PFAS testing data is available for Clay RWS/South Union under the EPA's UCMR5 monitoring program.
What water source does Clay RWS/South Union use? ▼
Clay RWS/South Union uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.