D27/100
Rio Grande Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 18,912 residents · Texas
What's In Rio Grande's Tap Water?
69
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
chlorate | 840.00 µg/L | — | Above Goal |
EPA Violation History
3
Violations (last 5yr)
0
Unresolved
2
Health-Related
TIER 1 — URGENTResolved
Violation related to Nitrate
When: July 1, 2023 – July 31, 2023Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2023 – November 13, 2023Enforcement: Resolving — corrective action underway
TIER 1 — URGENTResolved
Violation related to Nitrate
When: July 1, 2023 – July 31, 2023Rule: Surface Water Treatment RuleEnforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
CITY OF RIO GRANDE CITY
Population Served
18,912
Water Source
Surface Water
System ID
TX2140018
Frequently Asked Questions About Rio Grande Water
Is Rio Grande tap water safe to drink?
Rio Grande, Texas tap water receives a grade of D (27/100), which is considered poor. 0 contaminant(s) exceed EPA maximum contaminant levels and 46 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Rio Grande's water?
Of the 69 contaminants tested in Rio Grande's water supply, the most notable include chlorate. No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Rio Grande have any water quality violations?
Yes, Rio Grande has 46 EPA violation(s) on record, with the most recent in 2023. Violation types include TT, Other, MR. 6 of these are health-based violations, which are the most serious category.
Do I need a water filter in Rio Grande?
Rio Grande water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. 1 contaminant(s) exceed these stricter goals.
Where does Rio Grande's tap water come from?
Rio Grande's drinking water is sourced from surface water and supplied by CITY OF RIO GRANDE CITY. The system serves approximately 18,912 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Rio Grande's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Rio Grande's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Rio Grande's water compare to other cities in Texas?
Rio Grande's water quality score of 27/100 earns a grade of D, which is considered poor. This is a concerning score that suggests significant water quality issues. Visit our Texas state page to see how all cities in the state compare.
What should I do if I'm concerned about Rio Grande's water quality?
If you have concerns about Rio Grande's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (CITY OF RIO GRANDE CITY) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.