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Community Water System · PWS SD4600864

Grant-Roberts Rural Water System

Milbank, South Dakota 57252 - drinking water served from groundwater sources to 5,050 people, tracked in EPA SDWIS and UCMR5.

5,050
People served
10
EPA violations
0
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 10 drinking-water violations at Grant-Roberts Rural Water System - below the South Dakota per-system average.

10
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
5,050
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Grant-Roberts Rural Water System

Grant-Roberts Rural Water System is a private-owned community water system that delivers drinking water to 5,050 residents in Milbank, South Dakota (Grant County) through 2,020 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 10 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 7 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 Lead and Copper Rule, recorded in 3 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

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%).

Grant-Roberts Rural Water System's 10 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
5,050
Total Violations
10
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
2,020
County
Grant
School/Daycare
No
MCL Violations
0
Monitoring Violations
7
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Lead and Copper Rule MR 3 1998
E. COLI MR 2 2015
Nitrate MR 2 2022

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 58 samples detected PFAS.

Contaminant Date Result MRL Status
NEtFOSAA 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
PFMBA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 4/10/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 4/10/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 4/10/2023 <7.00 ppt 7.00 ppt Not Detected
NMeFOSAA 4/10/2023 <6.00 ppt 6.00 ppt Not Detected
PFPeA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 4/10/2023 <4.00 ppt 4.00 ppt Not Detected
PFTA 4/10/2023 <8.00 ppt 8.00 ppt Not Detected
PFDoA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
PFNA 4/10/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 4/10/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 4/10/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 4/10/2023 <2.00 ppt 2.00 ppt Not Detected
PFBA 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
11Cl-PF3OUdS 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 4/10/2023 <5.00 ppt 5.00 ppt Not Detected
ADONA 4/10/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 4/10/2023 <2.00 ppt 2.00 ppt Not Detected
6:2 FTS 10/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFNA 10/11/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 10/11/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 10/11/2023 <4.00 ppt 4.00 ppt Not Detected
PFDoA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFDA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 10/11/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 10/11/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 10/11/2023 <2.00 ppt 2.00 ppt Not Detected
ADONA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 10/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 10/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxS 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 10/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 10/11/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 10/11/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 10/11/2023 <20.00 ppt 20.00 ppt Not Detected

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 Grant-Roberts Rural Water System.

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 SD4600864 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 Nitrate MR 2 SDWIS / SD4600864 / 1040
2015 E. COLI MR 2 SDWIS / SD4600864 / 3014
1998 Lead and Copper Rule MR 3 SDWIS / SD4600864 / 5000

How Grant-Roberts Rural Water System Compares

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

Metric Grant-Roberts Rural Water System South Dakota avg Federal benchmark
Total violations 10 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 5,050 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 Grant-Roberts Rural Water System water safe to drink? ▼
Grant-Roberts Rural Water System (PWS ID: SD4600864) has 10 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 5,050 people using Groundwater sources.
How many people does Grant-Roberts Rural Water System serve? ▼
Grant-Roberts Rural Water System serves 5,050 people in Milbank, South Dakota. It is a Private-owned system using Groundwater water sources with 2,020 service connections.
What type of violations does Grant-Roberts Rural Water System have? ▼
Grant-Roberts Rural Water System has 10 total violations: 0 health-based violations (MCL exceedances or treatment failures), 7 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Grant-Roberts Rural Water System water? ▼
No. Grant-Roberts Rural Water System was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Grant-Roberts Rural Water System use? ▼
Grant-Roberts Rural Water System 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. PFAS data from EPA UCMR5 monitoring program (2023-2025). 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.