WaterVerge

Is Rio Grande, TX Tap Water Safe to Drink?

Graded B — but Strontium and Chlorate were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

19K residents served 1 water system PWSID: TX2140018
Overall Score
79.4 / 100
Violations
9 active
Last Updated
May 2026
Source
Surface water
#382 of 1067 in Texas Top 53% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
79.4/100
waterverge.com
B 79.4/100

Rio Grande, TX — Water Quality Report

Rio Grande's drinking water received a grade of B (79.4 out of 100), indicating good water quality. The city's 1 water system serves approximately 18,912 residents using surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 2 PFAS compounds in the water supply.

The system has 48 violations on record, including 6 health-based violations. 9 remain unresolved.

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

What to know about Rio Grande's water

Rio Grande ranks #382 out of 1067 cities in Texas for water quality, placing it mid-range in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

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.

Quality Breakdown

Water quality score

See methodology →
79.4 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
31.4/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
16/20
B
2 PFAS compounds detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Surface water.
Water Safety

Is Rio Grande, TX water safe to drink?

Concerns Identified

Rio Grande's drinking water has significant quality concerns based on EPA testing data. With a grade of B (79.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 18,912 residents using surface water (rivers, lakes, or reservoirs).

9
Active Violations
0.0 ppb
Lead (90th %ile)
2 compounds
PFAS Detected
1 event
Disaster History

Recent water quality updates for Rio Grande

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

PFAS
2 PFAS "forever chemical" compounds 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 Rio Grande's water quality assessment. Grade: B (79.4/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
3 drinking water violations recorded

2 health-based. Contaminants: Interim Enhanced Surface Water Treatment Rule, Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Disaster
HURRICANE RITA

Federal disaster declaration (FEMA DR-1606). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

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

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

Well within EPA limits.

PFAS (2 compounds) Elevated
Detected: Highest: lithium at 45.4000 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.

PFAS "forever chemicals" detected

UCMR 5 testing found 2 PFAS compounds in Rio Grande's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.

Compound Level EPA MCL Status
lithium 45.4000 µg/L 0.004 µg/L Within Limit
PFBA 0.0061 µg/L 0.004 µg/L Within Limit

Violation history

Rio Grande's water system has 48 total violations on record, including 6 health-based violations. 9 remain unresolved. 4 violations were issued in the last 5 years.

OtherTTMRMCL
Most recent violations:
Jul 2025 Consumer Confidence Rule Open
Jul 2023 Interim Enhanced Surface Water Treatment Rule Resolved
Jul 2023 Consumer Confidence Rule Open
Jul 2023 Interim Enhanced Surface Water Treatment Rule Resolved
Oct 2020 Lead and Copper Rule Open

Flood & environmental risk

Ector County has experienced 1 federally declared disaster 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.

HURRICANE RITA
Hurricane FEMA DR-1606

Where does Rio Grande's water come from?

Rio Grande's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 18,912 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment.

What Rio Grande residents can do

Install a water filter

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

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
45.4000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
21.6 µg/L
EPA MCL: 60 µg/L · 36% of limit
Within LimitUCMR 4 DataHAA6Br: 20.3 µg/LHAA9: 33.7 µg/L
Strontium
Inorganic
Over HRL
1540.0 µg/L
EPA Health Ref Level: 1,500 µg/L · +3% over limit
Over HRLUCMR 3 Data
Manganese
Inorganic
Detected
4.8 µg/L
EPA Secondary MCL: 50 µg/L · 10% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
3.75 µg/L
EPA Short-term HA: 21 µg/L · 18% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
840.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Molybdenum
Inorganic
Detected
6.11 µg/L
EPA Lifetime HA: 40 µg/L · 15% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
45.4 µg/L
State screening level: 60 µg/L · 76% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
2
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

48
Total violations
6
Health-based
9
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

48 Total
9 Active
6 Health-based
39 Resolved
Violations by category
Synthetic Organic Chemicals
24
Interim and Long Term 1 Enhanced Surface Water Treatment Rule
6
Total Coliform Rule
4
Consumer Confidence Rule
3
Lead and Copper Rule
3
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Jul 2023 Active
Consumer Confidence Rule
Other Violation 0
Oct 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2020 Active
Consumer Confidence Rule
Other Violation 0
Dec 2014 Active
Public Notice
Other Violation 0
Sep 2014 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 2010 Active
Public Notice
Other Violation 0
Jul 2009 Active
Public Notice
Other Violation 0
Active
Compliance Violation
Monitoring 0
Jul 2023 Resolved
Interim Enhanced Surface Water Treatment Rule
Treatment Technique
Health-Based Health Resolved Jul 2023
Jul 2023 Resolved
Interim Enhanced Surface Water Treatment Rule
Treatment Technique
Health-Based Health Resolved Jul 2023
Jan 2020 Resolved
Dinoseb
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
OXAMYL
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Dalapon
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Aldicarb sulfoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Aldicarb sulfone
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
1,2-DIBROMO-3-CHLOROPROPANE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Carbofuran
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
Aldicarb
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Jan 2020 Resolved
ETHYLENE DIBROMIDE
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2022
Showing 20 of 48 violations
Environmental Risk

Drought conditions

D2 — severe drought

Starr 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)
13.3%
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

1
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

Ector County has experienced 1 federally declared disaster since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE RITA
Hurricane FEMA #1606

Recommended water filters

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

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
2 PFAS compounds 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 45.400 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 0.006 HI µg/L PFAS 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 9.2 ppb from 1993 (9.2 ppb) to 2024 (0.0 ppb).
Contaminant Rankings

See how Rio Grande compares by contaminant

Explore where Rio Grande ranks among all Texas cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Surface Water
Operator
Local Government
Population Served
18,912
Water Systems
1
Water Source

Where Rio Grande's water comes from

Surface Water

Rio Grande's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 18,912 people through 1 water system.

Infrastructure

Water systems serving Rio Grande

System Name PWSID Population Source
CITY OF RIO GRANDE CITY TX2140018 18,912 SW
Regional Comparison

How Rio Grande compares

Full Texas rankings →

Rio Grande's score of 79.4/100 is above the average of 46/100 among major Texas cities. It outscores 9 of 10 nearby cities.

Rio Grande (this city)
79.4
Houston
27.8
Austin
31.2
Dallas
36.2
Fort Worth
34.5
Texas avg
46
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Frequently asked questions

Is Rio Grande, TX tap water safe to drink?

Rio Grande's water quality earned a grade of B (79.4/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #382 out of 1067 cities tested in Texas.

What contaminants are in Rio Grande's water?

Lead was measured at 0.0 ppb (90th percentile). 2 PFAS compounds were detected. 48 violations are on record.

How is Rio Grande'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 Rio Grande?

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

Where does Rio Grande's water come from?

Rio Grande's water is sourced from Surface water. The city has 1 water system serving approximately 18,912 residents.

What health violations has Rio Grande's water system had?

Rio Grande has 6 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 9 violations remain unresolved.

How does Rio Grande's water compare to other cities?

Rio Grande ranks #382 out of 1067 cities in Texas (better than 64% of state cities) and #8259 out of 15744 cities nationally (48th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.