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Community Water System · PWS SD4600224

New Underwood

New Underwood, South Dakota 57761 - drinking water served from groundwater sources to 679 people, tracked in EPA SDWIS and UCMR5.

679
People served
144
EPA violations
104
Health-based
Untested
UCMR5 result

The verdict

EPA records 144 drinking-water violations at New Underwood, 72% of them health-based - above the South Dakota per-system average.

144
Total EPA violations on record
72%
Health-based (MCL / treatment failure)
679
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: New Underwood

New Underwood is a local-owned community water system that delivers drinking water to 679 residents in New Underwood, South Dakota (Pennington County) through 269 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 144 total violations for this system , of which 104 (72%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 27 monitoring and reporting violations are on file. The most recent violation on record dates to 2022.

The most frequently cited contaminant at this system is Gross Alpha, Excl. Radon and U, recorded in 52 violations (MCL, health-based). 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%).

New Underwood's 144 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
679
Total Violations
144
Health-Based Violations
104
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
269
County
Pennington
School/Daycare
No
MCL Violations
104
Monitoring Violations
27
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Gross Alpha, Excl. Radon and U MCL 52 2010
Combined Radium (-226 and -228) MCL 40 2010
Coliform (TCR) MCL 12 1997
Toluene MR 5 2009
Combined Radium (-226 and -228) MR 4 2003
Gross Alpha, Excl. Radon and U MR 4 2003
Combined Uranium MR 3 2003
Thallium, Total MR 3 1995
Antimony, Total MR 3 1995
Chlorine MR 3 2022
Revised Total Coliform Rule MON 2 2022

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 New Underwood.

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 SD4600224 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
2022 Chlorine MR 3 SDWIS / SD4600224 / 0999
2022 Revised Total Coliform Rule MON 2 SDWIS / SD4600224 / 8000
2010 Gross Alpha, Excl. Radon and U MCL 52 SDWIS / SD4600224 / 4000
2010 Combined Radium (-226 and -228) MCL 40 SDWIS / SD4600224 / 4010
2009 Toluene MR 5 SDWIS / SD4600224 / 2991
2003 Combined Radium (-226 and -228) MR 4 SDWIS / SD4600224 / 4010
2003 Gross Alpha, Excl. Radon and U MR 4 SDWIS / SD4600224 / 4000
2003 Combined Uranium MR 3 SDWIS / SD4600224 / 4006
1997 Coliform (TCR) MCL 12 SDWIS / SD4600224 / 3100
1995 Thallium, Total MR 3 SDWIS / SD4600224 / 1085
1995 Antimony, Total MR 3 SDWIS / SD4600224 / 1074

How New Underwood Compares

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

Metric New Underwood South Dakota avg Federal benchmark
Total violations 144 86 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 104 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 679 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 New Underwood water safe to drink? ▼
New Underwood (PWS ID: SD4600224) has 144 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 679 people using Groundwater sources.
How many people does New Underwood serve? ▼
New Underwood serves 679 people in New Underwood, South Dakota. It is a Local-owned system using Groundwater water sources with 269 service connections.
What type of violations does New Underwood have? ▼
New Underwood has 144 total violations: 104 health-based violations (MCL exceedances or treatment failures), 27 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in New Underwood water? ▼
No PFAS testing data is available for New Underwood under the EPA's UCMR5 monitoring program.
What water source does New Underwood use? ▼
New Underwood 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.