WaterVerge

Is Nichols Hills, OK Tap Water Safe to Drink?

Graded D, with 6 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

4K residents served 1 water system PWSID: OK2005501
Overall Score
47.2 / 100
Violations
6 active
Last Updated
May 2026
Source
Groundwater
#273 of 358 in Oklahoma Top 87% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
DGRADE
Water Quality Grade
47.2/100
waterverge.com
D 47.2/100

Nichols Hills, OK — Water Quality Report

Nichols Hills's drinking water received a grade of D (47.2 out of 100), indicating poor water quality. The city's 1 water system serves approximately 4,020 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 96 violations on record, including 21 health-based violations. 6 remain unresolved.

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

What to know about Nichols Hills's water

Nichols Hills ranks #273 out of 358 cities in Oklahoma for water quality, placing it among the lowest-rated in the state.

Nichols Hills 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

The system has seen 69 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
47.2 out of 100 Grade D
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
0/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
14.2/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Nichols Hills, OK water safe to drink?

Concerns Identified

Nichols Hills's drinking water has significant quality concerns based on EPA testing data. With a grade of D (47.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 4,020 residents using groundwater (wells).

6
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
5 events
Disaster History

Recent water quality updates for Nichols Hills

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

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Nichols Hills's water quality assessment. Grade: D (47.2/100).

Violation
2 drinking water violations recorded

Contaminants: Total Haloacetic Acids (HAA5), TTHM.

Violation
2 drinking water violations recorded

1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.

Violation
33 drinking water violations recorded

Contaminants: LASSO, Heptachlor, Heptachlor epoxide.

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 Nichols Hills's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 16.0000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Nichols Hills's water system has 96 total violations on record, including 21 health-based violations. 6 remain unresolved. 69 violations were issued in the last 5 years.

MRTTRPTOtherMCL
Most recent violations:
Jan 2025 Total Haloacetic Acids (HAA5) Resolved
Jan 2025 TTHM Resolved
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Jan 2024 LASSO Resolved

Flood & environmental risk

Oklahoma County has experienced 5 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 Lake Hefner At Oklahoma City, North Canadian River At Morgan Rd Nr Yukon, Lake Hefner Canal Near Oklahoma City, North Canadian R At Hwy 66 At Oklahoma City, Lake Overholser Near Oklahoma City.

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

Where does Nichols Hills's water come from?

Nichols Hills's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 4,020 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Lake Hefner At Oklahoma City (lake), North Canadian River At Morgan Rd Nr Yukon (river), Lake Hefner Canal Near Oklahoma City (stream), North Canadian R At Hwy 66 At Oklahoma City (river), Lake Overholser Near Oklahoma City (lake).

What Nichols Hills residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Nichols Hills'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.

Monitor alerts during storms

Nichols Hills'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
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
16.0000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
Lithium
Inorganic
Detected
16.0 µg/L
State screening level: 60 µg/L · 27% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

96
Total violations
21
Health-based
6
Active / unresolved
Jan 2025
Most recent violation
Compliance Record

Violations & advisories

96 Total
6 Active
21 Health-based
90 Resolved
Violations by category
Synthetic Organic Chemicals
58
Total Coliform Rule
11
Stage 2 Disinfectants and Disinfection Byproducts Rule
6
Radionuclides and Revised Rad Rule
5
Inorganic Chemicals
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 2023 Active
Consumer Confidence Rule
Other Violation 0
Oct 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2017 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Jan 2025 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2025
Jan 2025 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2025
Jan 2024 Resolved
LASSO
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Heptachlor
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Heptachlor epoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
2,4-D
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
HEXACHLOROBENZENE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Benzo(a)pyrene
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Pentachlorophenol
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Total Polychlorinated Biphenyls (PCB)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
1,2-DIBROMO-3-CHLOROPROPANE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
ETHYLENE DIBROMIDE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Nitrate-Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Jan 2024 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2024
Showing 20 of 96 violations
Industrial pollution

Top industrial polluters within 10 miles of Nichols Hills

Industrial polluters nearby

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

Total reported releases to surface water: 6 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
PHILLIPS 66 CO OKLAHOMA CITY PRODUCTS TERMINAL
Petroleum Bulk Terminals · PHILLIPS 66 CO
OKLAHOMA CITY, OK73117
Xylene (mixed isomers)67.6 mi
OWENS CORNING ROOFING & ASPHALT L.L.C OKLAHOMA CITY
Petroleum · OWENS CORNING
OKLAHOMA CITY, OK73117
Polycyclic aromatic compounds07.4 mi
JETTA CORP
Plastics and Rubber · NA
EDMOND, OK73013
6.4 mi
NESTLE PURINA PETCARE CO
Food · NESTLE PURINA PETCARE CO
OKLAHOMA CITY, OK73114
5.0 mi
SRM INC-KELLY PLANT
Nonmetallic Mineral Product · SRM INC
EDMOND, OK73034
5.6 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Drought conditions

D3 — extreme drought

Oklahoma County is currently in D3 (extreme 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)
11.0%
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

5
Declared disasters
Sep 2005
Most recent
Flood
Most common type

Oklahoma County has experienced 5 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
Nov 1974
SEVERE STORMS & FLOODING
Flood FEMA #453
Jun 1974
SEVERE STORMS & FLOODING
Flood FEMA #441

Recommended water filters

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

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
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 16.000 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 ND HI µg/L PFAS Not 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 ND 0.004 µg/L PFAS Not Detected
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 decreased by 0.0 ppb from 1992 (0.0 ppb) to 2024 (0.0 ppb).
Contaminant Rankings

See how Nichols Hills compares by contaminant

Explore where Nichols Hills ranks among all Oklahoma cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
4,020
Water Systems
1
Water Source

Where Nichols Hills's water comes from

Groundwater

Nichols Hills'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 4,020 people through 1 water system.

Local Hydrology

Water bodies near Nichols Hills

Nichols Hills is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Lake Hefner At Oklahoma City
lake
North Canadian River At Morgan Rd Nr Yukon
river
Lake Hefner Canal Near Oklahoma City
stream
North Canadian R At Hwy 66 At Oklahoma City
river
Lake Overholser Near Oklahoma City
lake
Infrastructure

Water systems serving Nichols Hills

System Name PWSID Population Source
NICHOLS HILLS OK2005501 4,020 GW
Regional Comparison

How Nichols Hills compares

Full Oklahoma rankings →

Nichols Hills's score of 47.2/100 is on par with the average of 45/100 among major Oklahoma cities. It outscores 8 of 10 nearby cities.

Nichols Hills (this city)
47.2
Tulsa
48.5
Norman
38.4
Lawton
44.4
Oklahoma avg
45
City Profile

About Nichols Hills, OK

Wikipedia →

Nichols Hills is a city in Oklahoma County, Oklahoma, United States, and a part of the Oklahoma City metropolitan area. The population was 3,870 as of the 2020 census, a 4.3% increase from 2010.

Economic Profile
$194,576
Median Income
$930,701
Median Home Value
$1,375/mo
Median Rent
0.3%
Unemployment
Community
46.6
Median Age
755
People / sq mi
77.2%
College Educated
95.9%
Homeownership
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Frequently asked questions

Is Nichols Hills, OK tap water safe to drink?

Nichols Hills's water quality earned a grade of D (47.2/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #273 out of 358 cities tested in Oklahoma.

What contaminants are in Nichols Hills's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 96 violations are on record.

How is Nichols Hills'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 Nichols Hills?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Nichols Hills's water come from?

Nichols Hills's water is sourced from Groundwater. The city has 1 water system serving approximately 4,020 residents.

What health violations has Nichols Hills's water system had?

Nichols Hills has 21 health-based violations on record. The most recent violation was recorded in January 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 6 violations remain unresolved.

Is Nichols Hills's groundwater at risk of contamination?

Nichols Hills 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 96 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.

How does Nichols Hills's water compare to other cities?

Nichols Hills ranks #273 out of 358 cities in Oklahoma (better than 24% of state cities) and #13650 out of 15744 cities nationally (13th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.