Clay Rural Water System
EPA ID: SD4600626 · 4,780 people served · 10 ZIP codes
Over the past five years, Clay Rural Water System recorded 1 violation, all subsequently resolved through the EPA enforcement process — the supplier currently operates in good standing, with no active actions on file for its 4,780 residents.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Clay Rural Water System Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Clay Rural Water System serves a community with a median household income of $77,143 and an estimated 26,567 residents across its service area. Approximately 77% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Clay Rural Water System'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 2% of homes in Union County, South Dakota rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Wastewater Proximity Note: This service area ranks in the 65th percentile nationally for proximity to wastewater discharge points.
Infrastructure Risk
Detected Contaminants
How Clay Rural Water System compares to EPA limits
What This Means For You
Contaminant 0700 at 1 mg/L exceeds the EPA maximum of mg/L.
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
Clay Rural Water System (EPA ID: SD4600626) is a community water system in South Dakota that serves approximately 4,780 people from groundwater sources.
This system provides water to 10 ZIP codes across 10 communities.
Average Home Safety Score: C (65/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Contaminant 0700 | Other Violation | 1 | Yes |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 57073 | 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: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by SD or modeled from parcel and building-footprint data.
- 57001 — Alcester
- 57004 — Beresford
- 57010 — Burbank
- 57014 — Centerville
- 57025 — Elk Point
- 57034 — Hudson
- 57037 — Irene
- 57069 — Vermillion
- 57072 — Volin
- 57073 — Wakonda
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Clay Rural Water System (SD4600626) on EPA.gov.
Frequently Asked Questions
Is Clay Rural Water System water safe to drink?
Clay Rural Water System has recorded 1 health-based violation 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 Clay Rural Water System serve?
Clay Rural Water System serves approximately 4,780 people across 10 ZIP codes in South Dakota.
Where does Clay Rural Water System 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
Clay Rural Water System (EPA ID: SD4600626) — request the latest Consumer Confidence Report or ask about specific contaminants.