Delafield Square
EPA ID: WI2685812 · 587 people served · 4 ZIP codes
2 open EPA findings remain on record at Delafield Square — the utility supplies approximately 587 people.
Data: EPA SDWIS Last verified: 2026-04-02
Compliance Trajectory
Worsening · Risk tier: High · 95% chance of violation in next 12 months
Violations went from 3 (2021) to 10 (2025). The pattern suggests growing compliance challenges.
Service Area Map
Coverage area for Delafield Square Source: EPA SDWIS service area boundaries.
Service area boundary — Grade C
Service Area Demographics
The Delafield Square serves a community with a median household income of $110,791 and an estimated 74,902 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?
Delafield Square'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 Waukesha County, Wisconsin rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 70th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Detected Contaminants
How Delafield Square compares to EPA limits
What This Means For You
Atrazine at 1 mg/L exceeds the EPA maximum of 0.003 mg/L. Endocrine disruption, cardiovascular & reproductive effects. Consider granular activated carbon (GAC) filtration.
Consumer Confidence Report Rule at 4 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 3 mg/L exceeds the EPA maximum of mg/L.
Stage 2 DBP Rule at 2 mg/L exceeds the EPA maximum of mg/L.
Total Coliform at 1 presence exceeds the EPA maximum of presence.
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 12 detections recorded. 3 exceed federal EPA limits (4 ppt for PFOA/PFOS).
Atrazine 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
Delafield Square (EPA ID: WI2685812) is a community water system in Wisconsin that serves approximately 587 people from groundwater sources.
This system provides water to 4 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
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| January 17, 2025 | Total Coliform | Monitoring | Resolved |
| January 1, 2025 | Stage 1 DBP Rule | Monitoring | Resolved |
| October 17, 2024 | Stage 2 DBP Rule | Monitoring | Resolved |
| October 17, 2024 | Stage 2 DBP Rule | Health-based | Resolved |
| October 17, 2024 | Lead and Copper Rule | Monitoring | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Consumer Confidence Report Rule | Reporting Failure | 4 | No |
| Stage 1 DBP Rule | Treatment Failure | 3 | No |
| Stage 2 DBP Rule | Treatment Failure | 2 | Yes |
| Atrazine | Organic | 1 | Yes |
| Total Coliform | Microbiological | 1 | No |
| Lead and Copper Rule | Treatment Failure | 1 | No |
| Chlorine residual | Disinfectant | 1 | Yes |
| Revised Total Coliform Rule | Microbiological | 1 | No |
Health Risk Details
Atrazine (EPA limit: 0.003 mg/L)
Endocrine disruption, cardiovascular & reproductive effects At-risk groups: pregnant women, people in agricultural areas, rural communities in the Midwest corn belt.
Removal methods: granular activated carbon (GAC), carbon block filter, reverse osmosis. Find the right filter →
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 |
|---|---|---|---|
| 53018 | 0.00113 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: 3 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.
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Delafield Square (WI2685812) on EPA.gov.
Frequently Asked Questions
Is Delafield Square water safe to drink?
Delafield Square has recorded 3 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 Delafield Square serve?
Delafield Square serves approximately 587 people across 4 ZIP codes in Wisconsin.
Where does Delafield Square 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:
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.
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
Delafield Square (EPA ID: WI2685812) — request the latest Consumer Confidence Report or ask about specific contaminants.