WaterVerge

Is Earlsboro, OK Tap Water Safe to Drink?

Graded C+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

6K residents served 2 water systems PWSID: OK2006362
Overall Score
65.2 / 100
Violations
12 active
Last Updated
May 2026
Source
Groundwater
#137 of 358 in Oklahoma Top 74% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
C+GRADE
Water Quality Grade
65.2/100
waterverge.com
C+ 65.2/100

Earlsboro, OK — Water Quality Report

Earlsboro's drinking water received a grade of C+ (65.2 out of 100), indicating fair water quality. The city's 2 water systems serve approximately 5,622 residents using groundwater.

Lead levels were measured at 4.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 3 PFAS compounds, with levels exceeding EPA maximum contaminant levels in the water supply.

The system has 53 violations on record, including 4 health-based violations. 12 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Earlsboro's water

Earlsboro ranks #137 out of 358 cities in Oklahoma for water quality, placing it mid-range in the state.

Earlsboro relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

Of particular concern: PFAS "forever chemical" levels exceed the 2024 EPA maximum contaminant levels. These synthetic compounds don't break down naturally and require specialized filtration such as reverse osmosis or granular activated carbon.

The system has seen 8 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
65.2 out of 100 Grade C+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
31/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
14/20
C
Lead at 4.0 ppb (90th percentile).
Contaminants
10.2/20
D
3 PFAS compounds detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Earlsboro, OK water safe to drink?

Concerns Identified

Earlsboro's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (65.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 5,622 residents using groundwater (wells).

12
Active Violations
4.0 ppb
Lead (90th %ile)
3 compounds
PFAS Detected
4 events
Disaster History

Recent water quality updates for Earlsboro

A timeline of significant water quality events, violations, and data updates.

PFAS
3 PFAS "forever chemical" compounds detected

PFAS levels exceed EPA maximum contaminant levels. Reverse osmosis or activated carbon filtration recommended.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Earlsboro's water quality assessment. Grade: C+ (65.2/100).

Violation
3 drinking water violations recorded

1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Lead and Copper Rule.

Violation
1 drinking water violation recorded

Contaminants: Nitrate-Nitrite.

Violation
1 drinking water violation recorded

Contaminants: E. COLI.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3219). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Earlsboro's water supply.

Lead Within Limits
Detected: 4.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 1.49 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

PFAS (3 compounds) Elevated
Detected: Highest: lithium at 17.0000 µg/L Limit: 0.004 µg/L (EPA MCL)

PFAS "forever chemicals" exceed EPA maximum contaminant levels. Reverse osmosis or granular activated carbon filtration strongly recommended.

PFAS "forever chemicals" detected

UCMR 5 testing found 3 PFAS compounds in Earlsboro's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.

Compound Level EPA MCL Status
lithium 17.0000 µg/L 0.004 µg/L Within Limit
PFHxS 0.0220 µg/L 0.004 µg/L Within Limit
PFOS 0.0060 µg/L 0.004 µg/L Over MCL

Violation history

Earlsboro's water system has 53 total violations on record, including 4 health-based violations. 12 remain unresolved. 8 violations were issued in the last 5 years.

TTRPTMRMONOtherMCL
Most recent violations:
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 Lead and Copper Rule Open
Apr 2024 Nitrate-Nitrite Resolved
Aug 2023 E. COLI Open

Flood & environmental risk

Pottawatomie County has experienced 4 federally declared disasters since 1974. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Little River Near Tecumseh, Squirrel Creek At Shawnee, North Canadian River At Shawnee.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3219
SEVERE STORMS & FLOODING
Flood FEMA DR-778
SEVERE STORMS & FLOODING
Flood FEMA DR-693

Where does Earlsboro's water come from?

Earlsboro's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 5,622 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Little River Near Tecumseh (river), Squirrel Creek At Shawnee (river), North Canadian River At Shawnee (river).

What Earlsboro residents can do

Install a water filter

Recommended: Reverse osmosis system. This addresses the specific contaminants found in Earlsboro's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Earlsboro's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
4.0 ppb
EPA Action Level: 15 ppb · 26% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.49 mg/L
EPA Action Level: 1.3 mg/L · +15% over limit
Exceeds Limit
lithium
PFAS / Forever Chemical
Near MCL
17.0000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
Lithium
Inorganic
Detected
17.0 µg/L
State screening level: 60 µg/L · 28% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
3
Detected
1
Exceed EPA MCL
1.50
Hazard Index
PFOS max: 0.0060 µg/L
Compliance Record

Violation summary

53
Total violations
4
Health-based
12
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

53 Total
12 Active
4 Health-based
41 Resolved
Violations by category
Total Coliform Rule
17
Inorganic Chemicals
11
Lead and Copper Rule
5
Consumer Confidence Rule
4
Radionuclides and Revised Rad Rule
4
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Aug 2023 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
May 2017 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2016 Active
Consumer Confidence Rule
Other Violation 0
Jul 2015 Active
Consumer Confidence Rule
Other Violation 0
Jul 2013 Active
Consumer Confidence Rule
Other Violation 0
Jul 2012 Active
Consumer Confidence Rule
Other Violation 0
Jul 2011 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Apr 2024 Resolved
Nitrate-Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2024
Oct 2021 Resolved
Nitrate-Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2021
Sep 2021 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Sep 2021
Jul 2021 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2021
Jul 2013 Resolved
E. COLI
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 2013
Jul 2013 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jul 2013
Jul 2013 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 2013
Jul 2013 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 2013
Showing 20 of 53 violations
Industrial pollution

Top industrial polluters within 10 miles of Earlsboro

Industrial polluters nearby

Reported releases to surface water by facilities near Earlsboro, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
GEORG FISCHER CENTRAL PLASTICS LLC
Plastics and Rubber · GEORG FISCHER
SHAWNEE, OK74804
8.8 mi
VAULT PRESSURE CONTROL - SHAWNEE FACILITY
Machinery · PELICAN ENERGY PARTNERS
SHAWNEE, OK74804
9.2 mi
DANFOSS POWER SOLUTIONS
Machinery · DANFOSS POWER SOLUTIONS (US) CO
SHAWNEE, OK74804
9.0 mi
BISON METAL TECHNOLOGIES
Primary Metals · NA
SHAWNEE, OK74804
9.0 mi
LATHAM POOL PRODUCTS INC - SEMINOLE
Plastics and Rubber · LATHAM POOL PRODUCTS INC
SEMINOLE, OK74868
8.9 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D2 — severe drought

Pottawatomie County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

14
Weeks at D2+ (current streak)
10.7%
Months in D2+ (last 30y)
14
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

4
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Pottawatomie County has experienced 4 federally declared disasters since 1974. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3219
Oct 1986
SEVERE STORMS & FLOODING
Flood FEMA #778
Oct 1983
SEVERE STORMS & FLOODING
Flood FEMA #693
Jun 1974
SEVERE STORMS & FLOODING
Flood FEMA #441

Recommended water filters

Based on contaminants detected in Earlsboro's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
PFAS compounds exceed EPA maximum contaminant levels
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.49 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 17.000 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS 0.022 HI µg/L PFAS Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS 0.006 0.004 µg/L PFAS Over MCL
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has increased by 4.6 ppb from 1993 (0.0 ppb) to 2025 (4.6 ppb).

Copper level (90th percentile)

Latest reading: 1.490 mg/L (2004)

EPA action level: 1.3 mg/L

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
5,622
Water Systems
2
Water Source

Where Earlsboro's water comes from

Groundwater

Earlsboro's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 5,622 people through 2 water systems.

Local Hydrology

Water bodies near Earlsboro

Earlsboro is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Little River Near Tecumseh
river
Squirrel Creek At Shawnee
river
North Canadian River At Shawnee
river
Infrastructure

Water systems serving Earlsboro

System Name PWSID Population Source
TRI-COUNTY RWD #2 OK2006362 5,172 GW
SEMINOLE CO. RWD #7 OK2006756 450 GW
Regional Comparison

How Earlsboro compares

Full Oklahoma rankings →

Earlsboro's score of 65.2/100 is above the average of 45/100 among major Oklahoma cities. It outscores 9 of 10 nearby cities.

Earlsboro (this city)
65.2
Tulsa
48.5
Norman
38.4
Lawton
44.4
Oklahoma avg
45
City Profile

About Earlsboro, OK

Economic Profile
$64,063
Median Income
$159,633
Median Home Value
$775/mo
Median Rent
9.4%
Unemployment
Community
41.8
Median Age
21
People / sq mi
19.9%
College Educated
87.3%
Homeownership
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Frequently asked questions

Is Earlsboro, OK tap water safe to drink?

Earlsboro's water quality earned a grade of C+ (65.2/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #137 out of 358 cities tested in Oklahoma.

What contaminants are in Earlsboro's water?

Lead was measured at 4.0 ppb (90th percentile). 3 PFAS compounds were detected. 53 violations are on record.

How is Earlsboro's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Earlsboro?

PFAS compounds exceed EPA limits — a reverse osmosis or activated carbon filter is recommended.

Where does Earlsboro's water come from?

Earlsboro's water is sourced from Groundwater. The city has 2 water systems serving approximately 5,622 residents.

What health violations has Earlsboro's water system had?

Earlsboro has 4 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 12 violations remain unresolved.

Is Earlsboro's groundwater at risk of contamination?

Earlsboro uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 53 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

Why does Earlsboro have so many PFAS compounds in its water?

3 different PFAS "forever chemical" compounds were detected in Earlsboro's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. Some levels exceed the 2024 EPA maximum contaminant levels — a reverse osmosis or NSF-certified activated carbon filter is strongly recommended.

How does Earlsboro's water compare to other cities?

Earlsboro ranks #137 out of 358 cities in Oklahoma (better than 62% of state cities) and #11554 out of 15744 cities nationally (27th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.