Walnut Park
EPA ID: SD4600316 · 180 people served · 2 ZIP codes
In every reporting cycle over the past five years, Walnut Park has come through without a single EPA violation — a consistent performance across the full service population of approximately 180 residents that reflects both well-maintained infrastructure and reliable operational oversight.
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 2 (2024) to 2 (2025). The pattern suggests growing compliance challenges.
Service Area Map
Coverage area for Walnut Park Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The Walnut Park serves a community with a median household income of $64,970 and an estimated 17,507 residents across its service area. Approximately 46% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Walnut Park'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 Lawrence 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 90th percentile nationally for proximity to wastewater discharge points.
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
Walnut Park (EPA ID: SD4600316) is a community water system in South Dakota that serves approximately 180 people from groundwater sources.
This system provides water to 2 ZIP codes across 1 community.
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
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Walnut Park (SD4600316) on EPA.gov.
Frequently Asked Questions
Is Walnut Park water safe to drink?
Based on EPA records, Walnut Park has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Walnut Park serve?
Walnut Park serves approximately 180 people across 2 ZIP codes in South Dakota.
Where does Walnut Park 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.