Calvin
EPA ID: OK2003201 · 300 people served · 2 ZIP codes
Calvin earns a clean bill from EPA monitoring — no violations in five years across a service area of 300 people.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Calvin Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The Calvin serves a community with a median household income of $50,104 and an estimated 1,184 residents across its service area. Approximately 62% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 100% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
Calvin'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 3% of homes in Hughes County, Oklahoma 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 Oklahoma
System Overview
Calvin (EPA ID: OK2003201) is a community water system in Oklahoma that serves approximately 300 people from groundwater sources.
This system provides water to 2 ZIP codes across 2 communities.
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 Calvin (OK2003201) on EPA.gov.
Frequently Asked Questions
Is Calvin water safe to drink?
Based on EPA records, Calvin has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Calvin serve?
Calvin serves approximately 300 people across 2 ZIP codes in Oklahoma.
Where does Calvin 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.