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Community Water System · PWS SD4600226

North Sioux City

North Sioux City, South Dakota 57049 - drinking water served from groundwater sources to 3,042 people, tracked in EPA SDWIS and UCMR5.

3,042
People served
69
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 69 drinking-water violations at North Sioux City - below the South Dakota per-system average.

69
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
3,042
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: North Sioux City

North Sioux City is a local-owned community water system that delivers drinking water to 3,042 residents in North Sioux City, South Dakota (Union County) through 1,249 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 69 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 63 monitoring and reporting violations are on file. The most recent violation on record dates to 2008.

The most frequently cited contaminant at this system is Consumer Confidence Rule, recorded in 4 violations (Other). 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%).

North Sioux City's 69 violations sit below 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
3,042
Total Violations
69
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,249
County
Union
School/Daycare
No
MCL Violations
0
Monitoring Violations
63
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Consumer Confidence Rule Other 4 2003
Lead and Copper Rule MR 3 1999
1,2-DIBROMO-3-CHLOROPROPANE MR 2 2008
Carbofuran MR 2 1996
OXAMYL MR 2 1996
cis-1,2-Dichloroethylene MR 2 1999
Vinyl chloride MR 2 1999
1,1,1-Trichloroethane MR 2 1999
Tetrachloroethylene MR 2 1999
Xylenes, Total MR 2 1999
Carbon tetrachloride MR 2 1999
CHLOROBENZENE MR 2 1999
Styrene MR 2 1999
Benzene MR 2 1999
p-Dichlorobenzene MR 2 1999
Trichloroethylene MR 2 1999
Toluene MR 2 1999
DICHLOROMETHANE MR 2 1999
1,2-Dichloropropane MR 2 1999
1,2-Dichloroethane MR 2 1999
Ethylbenzene MR 2 1999
1,1,2-Trichloroethane MR 2 1999
ETHYLENE DIBROMIDE MR 2 2008
o-Dichlorobenzene MR 2 1999
Aldicarb MR 2 1996
Nitrate MR 2 1995
1,1-Dichloroethylene MR 2 1999
1,2,4-Trichlorobenzene MR 2 1999
Aldicarb sulfone MR 2 1996
Aldicarb sulfoxide MR 2 1996

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 North Sioux City.

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 SD4600226 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
2008 1,2-DIBROMO-3-CHLOROPROPANE MR 2 SDWIS / SD4600226 / 2931
2008 ETHYLENE DIBROMIDE MR 2 SDWIS / SD4600226 / 2946
2003 Consumer Confidence Rule Other 4 SDWIS / SD4600226 / 7000
1999 Lead and Copper Rule MR 3 SDWIS / SD4600226 / 5000
1999 cis-1,2-Dichloroethylene MR 2 SDWIS / SD4600226 / 2380
1999 Vinyl chloride MR 2 SDWIS / SD4600226 / 2976
1999 1,1,1-Trichloroethane MR 2 SDWIS / SD4600226 / 2981
1999 Tetrachloroethylene MR 2 SDWIS / SD4600226 / 2987
1999 Xylenes, Total MR 2 SDWIS / SD4600226 / 2955
1999 Carbon tetrachloride MR 2 SDWIS / SD4600226 / 2982
1999 CHLOROBENZENE MR 2 SDWIS / SD4600226 / 2989
1999 Styrene MR 2 SDWIS / SD4600226 / 2996
1999 Benzene MR 2 SDWIS / SD4600226 / 2990
1999 p-Dichlorobenzene MR 2 SDWIS / SD4600226 / 2969
1999 Trichloroethylene MR 2 SDWIS / SD4600226 / 2984

How North Sioux City Compares

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

Metric North Sioux City South Dakota avg Federal benchmark
Total violations 69 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 3,042 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 North Sioux City water safe to drink? ▼
North Sioux City (PWS ID: SD4600226) has 69 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 3,042 people using Groundwater sources.
How many people does North Sioux City serve? ▼
North Sioux City serves 3,042 people in North Sioux City, South Dakota. It is a Local-owned system using Groundwater water sources with 1,249 service connections.
What type of violations does North Sioux City have? ▼
North Sioux City has 69 total violations: 0 health-based violations (MCL exceedances or treatment failures), 63 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in North Sioux City water? ▼
No PFAS testing data is available for North Sioux City under the EPA's UCMR5 monitoring program.
What water source does North Sioux City use? ▼
North Sioux City 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.