WaterVerge

Is Karnack, TX Tap Water Safe to Drink?

Graded B-, with 18 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

2K residents served 2 water systems PWSID: TX1020019
Overall Score
73.5 / 100
Violations
18 active
Last Updated
May 2026
Source
Groundwater
#523 of 1067 in Texas Top 64% nationally
Local Government
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B-GRADE
Water Quality Grade
73.5/100
waterverge.com
B- 73.5/100

Karnack, TX — Water Quality Report

Karnack's drinking water received a grade of B- (73.5 out of 100), indicating fair water quality. The city's 2 water systems serve approximately 1,656 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 47 violations on record, including 13 health-based violations. 18 remain unresolved.

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

What to know about Karnack's water

Karnack ranks #523 out of 1067 cities in Texas for water quality, placing it mid-range in the state.

Karnack 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.

As a small community water system, Karnack may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

The system has seen 9 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
73.5 out of 100 Grade B-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
26.5/45
D
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Karnack, TX water safe to drink?

Concerns Identified

Karnack's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (73.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,656 residents using groundwater (wells).

18
Active Violations
0.0 ppb
Lead (90th %ile)
7 events
Disaster History

Recent water quality updates for Karnack

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Karnack's water quality assessment. Grade: B- (73.5/100).

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Disaster
HURRICANE BERYL

Federal disaster declaration (FEMA DR-4798). Hurricane event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Public Notice.

Violation
2 drinking water violations recorded

Contaminants: Public Notice, TTHM.

Disaster
TROPICAL STORMS MARCO AND LAURA

Federal disaster declaration (FEMA DR-3540). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

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

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

Well within EPA limits.

Violation history

Karnack's water system has 47 total violations on record, including 13 health-based violations. 18 remain unresolved. 9 violations were issued in the last 5 years.

MROtherMCLMON
Most recent violations:
Dec 2024 Lead and Copper Rule Open
Apr 2024 Public Notice Open
Mar 2023 Public Notice Open
Mar 2023 TTHM Open
Jan 2023 TTHM Resolved

Flood & environmental risk

Harrison County has experienced 7 federally declared disasters since 2005. 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 Big Cypress Ck Abv Sh 43 Nr Karnack.

HURRICANE BERYL
Hurricane FEMA DR-4798
TROPICAL STORMS MARCO AND LAURA
Hurricane FEMA DR-3540
SEVERE STORMS AND FLOODING
Flood FEMA DR-4269

Where does Karnack's water come from?

Karnack's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,656 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Big Cypress Ck Abv Sh 43 Nr Karnack (river).

What Karnack residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Karnack'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

Karnack'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
Compliance Record

Violation summary

47
Total violations
13
Health-based
18
Active / unresolved
Dec 2024
Most recent violation
Compliance Record

Violations & advisories

47 Total
18 Active
13 Health-based
29 Resolved
6 SNC
Violations by category
Stage 2 Disinfectants and Disinfection Byproducts Rule
10
Stage 1 Disinfectants and Disinfection Byproducts Rule
9
Total Coliform Rule
9
Lead and Copper Rule
7
Public Notice Rule and Revised PN Rule
5
Dec 2024 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 2024 Active
Public Notice
Other Violation 0
Mar 2023 Active
Public Notice
Other Violation 0
Mar 2023 Active
TTHM
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2018 Active
Public Notice
Other Violation 0
Apr 2016 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2015 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2014 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2014 Active
Public Notice
Other Violation 0
Oct 2013 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2011 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2010 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
May 2008 Active
Public Notice
Other Violation 0
Jul 2007 Active
Consumer Confidence Rule
Other Violation 0
Jan 2006 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jan 2023 Resolved
TTHM
Max Contaminant Level
Health-Based Health Resolved Mar 2023
Oct 2022 Resolved
TTHM
Max Contaminant Level
Health-Based Health Resolved Dec 2022
Showing 20 of 47 violations
Environmental Risk

Drought conditions

D3 — extreme drought

Harrison 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.

13
Weeks at D2+ (current streak)
14.8%
Months in D2+ (last 30y)
13
Weeks at D2+ (last 5y)

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

Environmental Risk

Flood & disaster history

7
Declared disasters
Jul 2024
Most recent
Hurricane
Most common type

Harrison County has experienced 7 federally declared disasters since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Jul 2024
HURRICANE BERYL
Hurricane FEMA #4798
Aug 2020
TROPICAL STORMS MARCO AND LAURA
Hurricane FEMA #3540
Apr 2016
SEVERE STORMS AND FLOODING
Flood FEMA #4269
Mar 2016
SEVERE STORMS, TORNADOES, AND FLOODING
Flood FEMA #4266
Sep 2008
HURRICANE IKE
Hurricane FEMA #1791
Sep 2008
HURRICANE IKE
Hurricane FEMA #3294

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.3 ppb from 1994 (2.3 ppb) to 2024 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
1,656
Water Systems
2
Water Source

Where Karnack's water comes from

Groundwater

Karnack'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 1,656 people through 2 water systems.

Local Hydrology

Water bodies near Karnack

Karnack is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Big Cypress Ck Abv Sh 43 Nr Karnack
river
Infrastructure

Water systems serving Karnack

System Name PWSID Population Source
CADDO LAKE WSC TX1020019 1,230 GW
CVWS SITE 1 TX1020047 426 GW
Regional Comparison

How Karnack compares

Full Texas rankings →

Karnack's score of 73.5/100 is above the average of 46/100 among major Texas cities. It outscores 8 of 10 nearby cities.

Karnack (this city)
73.5
Houston
27.8
Austin
31.2
Dallas
36.2
Fort Worth
34.5
Texas avg
46
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Frequently asked questions

Is Karnack, TX tap water safe to drink?

Karnack's water quality earned a grade of B- (73.5/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #523 out of 1067 cities tested in Texas.

What contaminants are in Karnack's water?

Lead was measured at 0.0 ppb (90th percentile). 47 violations are on record.

How is Karnack'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 Karnack?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Karnack's water come from?

Karnack's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,656 residents.

What health violations has Karnack's water system had?

Karnack has 13 health-based violations on record. The most recent violation was recorded in December 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 18 violations remain unresolved.

Is Karnack's groundwater at risk of contamination?

Karnack 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 47 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 Karnack's water compare to other cities?

Karnack ranks #523 out of 1067 cities in Texas (better than 51% of state cities) and #10075 out of 15744 cities nationally (36th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.