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Community Water System · PWS SD4600060

Jefferson

Jefferson, South Dakota 57038 - drinking water served from groundwater sources to 475 people, tracked in EPA SDWIS and UCMR5.

475
People served
79
EPA violations
13
Health-based
Untested
UCMR5 result

The verdict

EPA records 79 drinking-water violations at Jefferson, 16% of them health-based - below the South Dakota per-system average.

79
Total EPA violations on record
16%
Health-based (MCL / treatment failure)
475
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Jefferson

Jefferson is a local-owned community water system that delivers drinking water to 475 residents in Jefferson, South Dakota (Union County) through 235 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 79 total violations for this system , of which 13 (16%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 62 monitoring and reporting violations are on file. The most recent violation on record dates to 2014.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 9 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%).

Jefferson's 79 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
475
Total Violations
79
Health-Based Violations
13
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
235
County
Union
School/Daycare
No
MCL Violations
9
Monitoring Violations
62
Treatment Tech Violations
4

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 9 2010
Stage 1 Disinfectants and Disinfection Byproducts Rule TT 4 2014
Coliform (TCR) MR 4 1994
Arsenic MR 2 1990
Chromium MR 2 1990
Selenium MR 2 1990
cis-1,2-Dichloroethylene MR 2 1994
Tetrachloroethylene MR 2 1994
Ethylbenzene MR 2 1994
DICHLOROMETHANE MR 2 1994
1,1,2-Trichloroethane MR 2 1994
CHLOROBENZENE MR 2 1994
o-Dichlorobenzene MR 2 1994
Benzene MR 2 1994
p-Dichlorobenzene MR 2 1994
Trichloroethylene MR 2 1994
Toluene MR 2 1994
Mercury MR 2 1990
1,2,4-Trichlorobenzene MR 2 1994
Xylenes, Total MR 2 1994
1,2-Dichloroethane MR 2 1994
Vinyl chloride MR 2 1994
1,2-Dichloropropane MR 2 1994
1,1,1-Trichloroethane MR 2 1994
Cadmium MR 2 1990
Styrene MR 2 1994
trans-1,2-Dichloroethylene MR 2 1994
Barium MR 2 1990
Carbon tetrachloride MR 2 1994
Fluoride MR 2 1990

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 Jefferson.

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 SD4600060 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
2014 Stage 1 Disinfectants and Disinfection Byproducts Rule TT 4 SDWIS / SD4600060 / 0400
2010 Coliform (TCR) MCL 9 SDWIS / SD4600060 / 3100
1994 Coliform (TCR) MR 4 SDWIS / SD4600060 / 3100
1994 cis-1,2-Dichloroethylene MR 2 SDWIS / SD4600060 / 2380
1994 Tetrachloroethylene MR 2 SDWIS / SD4600060 / 2987
1994 Ethylbenzene MR 2 SDWIS / SD4600060 / 2992
1994 DICHLOROMETHANE MR 2 SDWIS / SD4600060 / 2964
1994 1,1,2-Trichloroethane MR 2 SDWIS / SD4600060 / 2985
1994 CHLOROBENZENE MR 2 SDWIS / SD4600060 / 2989
1994 o-Dichlorobenzene MR 2 SDWIS / SD4600060 / 2968
1994 Benzene MR 2 SDWIS / SD4600060 / 2990
1994 p-Dichlorobenzene MR 2 SDWIS / SD4600060 / 2969
1994 Trichloroethylene MR 2 SDWIS / SD4600060 / 2984
1994 Toluene MR 2 SDWIS / SD4600060 / 2991
1994 1,2,4-Trichlorobenzene MR 2 SDWIS / SD4600060 / 2378

How Jefferson Compares

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

Metric Jefferson South Dakota avg Federal benchmark
Total violations 79 86 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 13 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 475 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 Jefferson water safe to drink? ▼
Jefferson (PWS ID: SD4600060) has 79 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 475 people using Groundwater sources.
How many people does Jefferson serve? ▼
Jefferson serves 475 people in Jefferson, South Dakota. It is a Local-owned system using Groundwater water sources with 235 service connections.
What type of violations does Jefferson have? ▼
Jefferson has 79 total violations: 13 health-based violations (MCL exceedances or treatment failures), 62 monitoring/reporting violations, and 4 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Jefferson water? ▼
No PFAS testing data is available for Jefferson under the EPA's UCMR5 monitoring program.
What water source does Jefferson use? ▼
Jefferson 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.