waterbycounty

County water report

Brewster County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Brewster County, Texas.

Water grade

F

Water score

13.1

State rank

#169

of 254

Health violations

20

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

8

858 recent measurements

Live streamflow

1%

Rio Grande nr Castolon, TX

Water at a glance

Key Water Indicators for Brewster County

EPA SDWIS

Safety Grade

F

Score: 13.1 / 100

EPA SDWIS

Active Violations

20

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

1% of mean

Rio Grande nr Castolon, TX

EPA WQP

Monitoring Sites

8

858 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

F

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

13.1/100

Health violations

20

Health-based violations

Violations per 100K served

232.4

Population-normalized SDWIS rate

Editorial analysis

Understanding Brewster County’s Water

Drinking Water Quality Overview

EPA SDWIS

Brewster County's water systems carry a failing grade, scoring 13.1 out of 100. Over the past five years, EPA SDWIS records 20 health-based violations — a pattern that public water utilities are required to disclose and correct.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T13:15:00.000-05:00) puts Rio Grande at 7.0 cfs — well below its long-term average at 1% of mean — low-flow conditions worth noting for water-dependent ecosystems. Streamflow is a leading indicator of drought stress, sediment load, and dilution capacity: low flows concentrate pollutants and warm water temperatures, stressing aquatic life and, in surface-water-dependent systems, the source water quality for treatment plants.

Monitoring Network

EPA WQP

EPA's Water Quality Portal (WQP) aggregates monitoring data from federal, state, and tribal agencies. Brewster County has limited coverage with 8 active monitoring sites with 858 recent measurements on record. Predominant monitoring categories include physical and inorganics, major, non-metals. More monitoring sites generally indicate greater scientific attention to local water conditions — and provide the baseline data that regulators use to set future impairment listings.

Editorial advisory

What the data suggests for Brewster County

Water Verdict

Brewster County receives a poor water quality assessment with a grade of F and a score of 13.1 out of 100. The water supply has documented quality issues. Residents are strongly encouraged to use filtered or bottled water for drinking and to stay informed about utility improvement plans.

Violation Context

Brewster County has recorded 20 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 232.4 violations per 100,000 people served, this rate is high and signals significant water quality management issues.

Consumer Guidance

Drinking-water compliance in Brewster County is rated Grade F, reflecting significant health-based violations in the recent reporting period. Brewster County's drinking-water compliance score is 13.1 out of 100. An NSF 53 or NSF 58-certified filter is recommended for drinking and cooking water. Check the Consumer Confidence Report from your utility to identify the specific contaminants and required corrective actions — utilities are legally required to notify customers of violations. There are 8 active water-quality monitoring sites in Brewster County. A pipeline streamflow snapshot from the Rio Grande gauge is also available on this page.

Regional Context

Brewster County has poorer water quality than the average county in Texas. Its water score is 17.3 points lower than the state average, suggesting more challenges with contamination control or infrastructure than neighboring counties.

Advisory text summarizes county-level public records and is not a replacement for your utility's current Consumer Confidence Report or direct local notices.

Past 5 years

Water Quality Monitoring

Monitoring Sites

8

Active in the past 5 years

Measurements Recorded

858

858 total readings

Most Measured

  • Physical
  • Inorganics, Major, Non-metals
  • Inorganics, Major, Metals

Categories measured most frequently

Data from the EPA Water Quality Portal (WQP), aggregating monitoring records from federal, state, and tribal sources. Each measurement represents a single sample analyzed for a specific characteristic (e.g., E. coli, pH, dissolved oxygen, nitrogen).

Live USGS Streamgage

River & Stream Conditions

Current Discharge

7.01cfs

May 14, 6:15 PM UTC

vs Long-Term Average

1%

Well below typical

Primary Streamgage

Rio Grande nr Castolon, TX

USGS site
08374550
Long-term mean
662 cfs

One representative streamgage (the one with the largest drainage area in the county). Many counties have multiple gauges; this view summarizes the primary one. The long-term mean is the full-record annual average; the percent-of-typical value compares the latest reading against that average.

Free tool

Estimate Your Water Costs

Water Cost Estimate

3

3 people  ·  ~225 gal/day

Annual Total

$558

Monthly

$47

Water Bill

$558/yr

Filter Cost

$0/yr

Safety Grade for Brewster County:FFailing

High violation count or severe watershed conditions.

Estimates use the national average residential water rate ($0.0068/gal, EPA/AWWA 2023) and EPA WaterSense per-person consumption baseline (75 gal/person/day). Actual bills vary by utility, usage tier, and local infrastructure fees. For informational purposes only.

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Frequently Asked Questions

What is the water quality in Brewster County, Texas?
Brewster County, Texas has a drinking-water quality grade of F with a score of 13.1/100, based on EPA SDWIS compliance data. The county has 20 health-based drinking water violations over the past 5 years. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in Brewster County?
Brewster County has 20 health-based drinking water violations recorded by the EPA over the past 5 years. Health-based violations indicate instances where contaminant levels exceeded EPA Maximum Contaminant Levels (MCLs). Violations may have been resolved — check with your local water utility for current status.
How much water-quality monitoring happens in Brewster County?
EPA's Water Quality Portal records 858 measurements from 8 monitoring sites in Brewster County over the past five years. The most frequently measured characteristic groups are Physical, Inorganics, Major, Non-metals, Inorganics, Major, Metals. Each measurement is a single sample analyzed for one characteristic (E. coli, pH, dissolved oxygen, etc.). High monitoring density means more scientific evidence behind any reported signal — it does not by itself indicate water quality.
What's happening with rivers in Brewster County right now?
Brewster County's primary USGS streamgage on the Rio Grande has a pipeline snapshot of 7.01 cubic feet per second — 1% of the long-term mean of 662.47 cfs. This is well below typical — often a signal of drought stress on source water. For the latest gauge feed, visit waterdata.usgs.gov.
How does Brewster County water compare to the Texas average?
Brewster County's SDWIS water quality score of 13.1/100 is lower than the Texas state average of 30.4. The average water quality grade across Texas is F, based on data from 254 counties with available SDWIS data.
Is tap water safe to drink in Brewster County?
Based on EPA SDWIS data, Brewster County has a water quality grade of F (13.1/100). This indicates below-average compliance with significant violations. Residents may want to consider home water filtration or independent testing. The grade speaks to the public water system, not the watershed — for watershed-level concerns, see the Watershed Health zone. For the most up-to-date information, contact your local water utility or review your Consumer Confidence Report (CCR).
Why does Brewster County have so many water violations?
Brewster County has 20 health-based drinking water violations on record from the EPA SDWIS database. A higher violation count can result from aging infrastructure, underfunded water utilities, agricultural runoff contamination, or industrial pollution. Counties with more water systems may also see more violations simply due to scale. Residents concerned about water quality should consider independent water testing and home filtration systems.
How does Brewster County rank for water quality in Texas?
Brewster County ranks #169 out of 254 counties in Texas by SDWIS water quality score (1 = best). With a score of 13.1/100, it falls in the middle third of counties statewide. The ranking reflects EPA SDWIS compliance only — not watershed impairment, monitoring density, or streamflow, which are tracked separately on this page.

Data Sources

Drinking-water compliance data from the EPA Safe Drinking Water Information System (SDWIS) via the ECHO enforcement database. Scores reflect compliance history and health-based violation counts.

Water-quality monitoring counts from the EPA Water Quality Portal (WQP), federated USGS, EPA, and state agency sampling records over a rolling 5-year window.

Live streamflow from the USGS National Water Information System (NWIS), continuous discharge measurements from the largest-drainage gauge in each county, compared against the full-record long-term annual mean.

Disclaimer: This data is informational only. It is not health, legal, or professional advice. For concerns about your specific water supply, contact your local water utility.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor