Brown-day-marshall Rws
EPA ID: SD4600882 · 5,673 people served · 23 ZIP codes
Unlike fully compliant utilities, Brown-day-marshall Rws has 2 outstanding EPA violations for approximately 5,673 residents.
Data: EPA SDWIS Last verified: 2026-04-02
Compliance Trajectory
Stable · Risk tier: High · 95% chance of violation in next 12 months
Violations went from 3 (2021) to 3 (2025). Violation counts have remained relatively steady.
Service Area Map
Coverage area for Brown-day-marshall Rws Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Brown-day-marshall Rws serves a community with a median household income of $67,663 and an estimated 51,528 residents across its service area. Approximately 73% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 38% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
Brown-day-marshall Rws's water is pumped from underground aquifers. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
About 0% of homes in Day County, South Dakota rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How Brown-day-marshall Rws compares to EPA limits
What This Means For You
Haloacetic Acids (HAA5) at 1 mg/L exceeds the EPA maximum of 0.06 mg/L. Cancer risk; reproductive & developmental effects. Consider granular activated carbon (GAC) filtration.
Revised Total Coliform Rule at 3 presence exceeds the EPA maximum of presence.
Copper at 2 mg/L exceeds the EPA maximum of 1.3 mg/L.
Contaminant 1036 at 1 mg/L exceeds the EPA maximum of mg/L.
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 1 detection recorded.
Haloacetic Acids (HAA5) was detected in this water system. granular activated carbon (GAC) filtration can reduce exposure.
Find a certified water filter →Comparable Water Systems
Similar-sized systems in South Dakota
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
BROWN-DAY-MARSHALL RWS (EPA ID: SD4600882) is a community water system in South Dakota that serves approximately 5,673 people from groundwater sources.
This system provides water to 23 ZIP codes across 23 communities.
Average Home Safety Score: C (59/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| July 1, 2025 | Surface Water Treatment Rule | Monitoring | Unresolved |
| July 1, 2025 | Consumer Confidence Report Rule | Monitoring | Unresolved |
| May 14, 2025 | Chlorine residual | Health-based | Unresolved |
| April 1, 2024 | Revised Total Coliform Rule | Monitoring | Unresolved |
| November 29, 2023 | Chlorine residual | Health-based | Resolved |
| October 1, 2023 | Stage 1 DBP Rule | Monitoring | Resolved |
| August 1, 2023 | Haloacetic Acids (HAA5) | Monitoring | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Chlorine residual | Disinfectant | 4 | Yes |
| Revised Total Coliform Rule | Microbiological | 3 | No |
| Copper | Inorganic | 2 | No |
| Contaminant 1036 | Other Violation | 1 | No |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 1 | No |
| Total Coliform | Microbiological | 1 | No |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
| Surface Water Treatment Rule | Treatment Failure | 1 | No |
| Consumer Confidence Report Rule | Reporting Failure | 1 | No |
| Contaminant 0700 | Other Violation | 1 | Yes |
Health Risk Details
Chlorine (Residual Disinfectant) (EPA limit: 4 mg/L (MRDL — Maximum Residual Disinfectant Level))
Irritation & DBP formation at high levels; protective at normal treatment levels At-risk groups: people with asthma or chemical sensitivities, kidney dialysis patients (water must be dechlorinated).
Removal methods: granular activated carbon (GAC), KDF media filter, carbon block filter. Find the right filter →
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 57279 | 0.007 mg/L | No | N/A |
| 57232 | 0.002 mg/L | No | N/A |
| 57255 | 0.002 mg/L | No | N/A |
| 57260 | 0.002 mg/L | No | N/A |
| 57266 | 0.002 mg/L | No | N/A |
| 57430 | 0.002 mg/L | No | N/A |
| 57227 | 0.001 mg/L | No | N/A |
| 57270 | 0.001 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
Coverage: 22 ZIP codes confirmed via EPA Community Water System Service Area Boundaries v3 plus 1 additional ZIP inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
- 57219 — Bristol
- 57224 — Claire City
- 57227 — Corona
- 57232 — Eden
- 57247 — Lake City
- 57255 — New Effington
- 57257 — Peever
- 57260 — Rosholt
- 57262 — Sisseton
- 57266 — Summit
- 57270 — Veblen
- 57273 — Waubay
- 57279 — Wilmot
- 57401 — Aberdeen
- 57421 — Amherst
- 57430 — Britton
- 57432 — Claremont
- 57433 — Columbia
- 57441 — Frederick
- 57445 — Groton
- 57454 — Langford
- 57460 — Mansfield
- 57481 — Westport
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Brown-day-marshall Rws (SD4600882) on EPA.gov.
Frequently Asked Questions
Is Brown-day-marshall Rws water safe to drink?
Brown-day-marshall Rws has recorded 4 health-based violations in the past 5 years. While the system is required to treat water to meet federal standards, you may want to consider additional precautions such as a certified water filter.
How many people does Brown-day-marshall Rws serve?
Brown-day-marshall Rws serves approximately 5,673 people across 23 ZIP codes in South Dakota.
Where does Brown-day-marshall Rws get its water?
The primary water source is groundwater.
Federal UCMR5 PFAS Monitoring: Tested Clean
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were detected.
Current MCL reflects the lowest state-enforceable limit (NYS 10 ppt for PFOA/PFOS, effective August 2020). The federal final MCL of 4 ppt for PFOA/PFOS (EPA April 2024 rule) is not enforceable until April 2029. Detections above 4 ppt but below 10 ppt are below current MCL but above the future federal limit.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.
How Water Systems Appear in Rankings
Water systems are evaluated by violation history, contaminant detections, and service population. Larger systems with more service connections appear in more rankings.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
Brown-day-marshall Rws (EPA ID: SD4600882) — request the latest Consumer Confidence Report or ask about specific contaminants.