Oronoco
EPA ID: MN1550036 · 2,040 people served · 5 ZIP codes
Looking at the EPA enforcement file for Oronoco, 2 violations appear in the five-year dataset, but none remain open — the utility has addressed each finding and is in current compliance, with no pending enforcement affecting the 2,040 people in its service area.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Oronoco Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Oronoco serves a community with a median household income of $104,146 and an estimated 89,346 residents across its service area. Approximately 51% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Oronoco'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 1% of homes in Olmsted County, Minnesota 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 Oronoco 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.
Stage 1 DBP Rule 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
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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
Oronoco (EPA ID: MN1550036) is a community water system in Minnesota that serves approximately 2,040 people from groundwater sources.
This system provides water to 5 ZIP codes across 4 communities.
Average Home Safety Score: C (67/100)
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 |
|---|---|---|---|
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 1 | No |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
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 MN or modeled from parcel and building-footprint data.
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Oronoco (MN1550036) on EPA.gov.
Frequently Asked Questions
Is Oronoco water safe to drink?
Oronoco has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does Oronoco serve?
Oronoco serves approximately 2,040 people across 5 ZIP codes in Minnesota.
Where does Oronoco get its water?
The primary water source is groundwater.
Contact Your Water Utility
Public-record contact information for the water utility serving this system. Use these channels to request water quality reports, ask about service, or report issues directly.
Contact information from Oronoco Consumer Confidence Report.
ZipCheckup is not affiliated with this water utility, does not act as its agent, and does not provide customer support for it. Contact details shown are public-record information from CCR filings. For service issues, contact the utility directly using the information above.
Treatment regime
How this utility classifies its treatment process and what each reported treatment chemical does.
Treatment chemicals and what each one does
Chemical names are reported verbatim by the utility. Purpose categories are ZipCheckup annotations based on standard drinking-water treatment practice.
Treatment classification and chemical list sourced from Oronoco Consumer Confidence Report.
Treatment intensity is a ZipCheckup-derived classification based on the chemicals and processes the utility reports. Chemicals and contamination sources are taken verbatim from the utility's CCR filing. Routine federal monitoring and contaminant testing shown elsewhere on this page determine whether the water meets safety standards, not the treatment classification.
PFAS Substances Detected in This System
This water system's Consumer Confidence Report disclosed the following PFAS compounds. Levels are from the utility's most recent reporting cycle.
In April 2024, EPA finalized the first National Primary Drinking Water Regulation for six PFAS. Public water systems have until 2029 to comply. EPA — PFAS regulation overview →
Source: Consumer Confidence Report disclosed by Oronoco.
ZipCheckup is not affiliated with this water utility. PFAS detection data is sourced from public Consumer Confidence Reports filed by the utility itself.
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.
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
Oronoco (EPA ID: MN1550036) — request the latest Consumer Confidence Report or ask about specific contaminants.