Public Water System

GRANDFIELD

PWSID OK2007103 · Oklahoma · 1,110 people served

Failing

GRANDFIELD is an EPA-regulated public water system in Oklahoma (PWSID OK2007103). It serves an estimated 1,110 residents — a rural community of customers — across 1 community across 1 ZIP code.

Over the past five years, GRANDFIELD has recorded 133 EPA health-based violations. The grade of F summarizes this compliance pattern. Specific contaminants, dates, and rule citations are listed in the violation history below.

Service Area

Loading map...

Centered on the averaged ZIP-code centroid of 1 ZIP served.

Population

1,110

Cities

ZIPs

Violations

133

EPA Health-Based Violations

Health-based Maximum Contaminant Level (MCL) violations on file for GRANDFIELD over the past five years of EPA SDWIS reporting.

Mercury (Inorganic)chemical

EPA Code 1038 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.002 mg/L

Last Reading

12 MG/L

First Reported

Jan 2021

Most Recent

Oct 2025

What this violation means

Inorganic mercury in drinking water primarily damages kidneys. Most mercury exposure for Americans comes from fish (methylmercury), but localized water contamination occurs near refineries, coal-burning plants, and certain landfills.

Recommended precautions

→Reverse osmosis and distillation remove inorganic mercury.
→Activated carbon adsorption works for mercury but capacity is limited.
→Test private wells near industrial sites or landfills.

Read the complete guide to Mercury (Inorganic)

Total Trihalomethanes (TTHMs)disinfectant

EPA Code 2950 · Maximum Contaminant Level Exceedance

violations

EPA Limit

0.08 mg/L

Last Reading

.086 MG/L

First Reported

Jan 2021

Most Recent

Jan 2024

What this violation means

Total Trihalomethanes (TTHMs) form when chlorine reacts with naturally occurring organic matter — leaves, soil, algae — in source water. They are among the most commonly reported violations because utilities pulling from surface water (rivers, lakes, reservoirs) struggle to balance disinfection with byproduct formation. Long-term exposure has been linked to bladder cancer and adverse pregnancy outcomes.

Recommended precautions

→Activated carbon filters (pitcher, faucet, or under-sink) effectively reduce TTHMs.
→Letting water sit uncovered allows TTHMs to off-gas — leave a pitcher in the fridge for several hours.
→Shower with the bathroom fan on; TTHMs can volatilize into the air during hot showers.
→Boiling reduces TTHMs through volatilization, but only after extended boiling.

Read the complete guide to Total Trihalomethanes (TTHMs)

Source: EPA Safe Drinking Water Information System (SDWIS). Health-based violations only. Older violations may have been resolved; check your utility's most recent Consumer Confidence Report for current status.

Cities Served by GRANDFIELD

GRANDFIELD

ZIP Codes Served

73546

About this system

EPA records this system as PWSID OK2007103. Data reflects the most recent EPA SDWIS publication as of 2026-05-18. Public Water System Identifiers (PWSIDs) are assigned by the EPA's Safe Drinking Water Act program to track every regulated water utility in the United States. The first two letters typically indicate the state primacy agency. For real-time water quality information, contact GRANDFIELD directly or review their annual Consumer Confidence Report (CCR).