Hermosa-old System
EPA ID: SD4600154 · 420 people served · 1 ZIP code
Five years of EPA monitoring have produced no violations for Hermosa-old System — the supplier serving 420 residents has kept every contaminant level within federal limits, a result that places it among the top-performing utilities for systems with a service population of comparable size.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Hermosa-old System Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The Hermosa-old System serves a community with a median household income of $110,673 and an estimated 2,211 residents across its service area.
💧 Where Does Your Water Come From?
Hermosa-old 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 Custer 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
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
Hermosa-old System (EPA ID: SD4600154) is a community water system in South Dakota that serves approximately 420 people from groundwater sources.
This system serves ZIP code 57744 in Hermosa.
Violation History
Lead & Copper
No Lead and Copper Rule sampling data available for this water system.
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
- 57744 — Hermosa
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Hermosa-old System (SD4600154) on EPA.gov.
Frequently Asked Questions
Is Hermosa-old System water safe to drink?
Based on EPA records, Hermosa-old System has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Hermosa-old System serve?
Hermosa-old System serves approximately 420 people across 1 ZIP code in South Dakota.
Where does Hermosa-old System get its water?
The primary water source is groundwater.
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
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.