Is Sonora, TX Tap Water Safe to Drink?
Graded B-, with 15 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
73.5/100
waterverge.com Sonora, TX — Water Quality Report
Sonora's drinking water received a grade of B- (73.5 out of 100), indicating fair water quality. The city's 1 water system serves approximately 2,766 residents using groundwater.
Lead levels were measured at 1.2 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 24 violations on record, including 2 health-based violations. 15 remain unresolved.
What to know about Sonora's water
Sonora ranks #522 out of 1067 cities in Texas for water quality, placing it mid-range in the state.
Sonora 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, Sonora may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Sonora, TX water safe to drink?
Sonora'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 1 water system serves approximately 2,766 residents using groundwater (wells).
Recent water quality updates for Sonora
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Sonora's water quality assessment. Grade: B- (73.5/100).
Federal disaster declaration (FEMA DR-4879). Flood event — may have impacted local water infrastructure.
Contaminants: Consumer Confidence Rule.
Contaminants: Public Notice.
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
Federal disaster declaration (FEMA DR-4416). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Sonora's water supply.
Well within EPA limits.
Violation history
Sonora's water system has 24 total violations on record, including 2 health-based violations. 15 remain unresolved. 6 violations were issued in the last 5 years.
Flood & environmental risk
Sutton County has experienced 3 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.
Where does Sonora's water come from?
Sonora's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,766 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Sonora residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Sonora's water.
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.
Sonora'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.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Sonora
Industrial polluters nearby
Reported releases to surface water by facilities near Sonora, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
JACAM MANUFACTURING 2013 LLC - JACAM SOUTHWEST SONORA SONORA, TX76950 | — | — | 3.8 mi |
MULTI-CHEM GROUP SONORA TX FACILITY SONORA, TX76950 | — | — | 0.5 mi |
SONORA GAS PLANT SONORA, TX76950 | — | — | 9.8 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Sutton County has experienced 3 federally declared disasters since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 1.2 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Sonora compares by contaminant
Explore where Sonora ranks among all Texas cities for specific contaminants.
Water source & infrastructure
Where Sonora's water comes from
Sonora'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 2,766 people through 1 water system.
Water systems serving Sonora
| System Name | PWSID | Population | Source |
|---|---|---|---|
| CITY OF SONORA | TX2180001 | 2,766 | GW |
How Sonora compares
Full Texas rankings →Sonora's score of 73.5/100 is above the average of 46/100 among major Texas cities. It outscores 8 of 10 nearby cities.
Nearby cities
View Texas rankings →About Sonora, TX
Learn more about your water
Guides and resources related to Sonora's water quality findings.
Explore water quality across Sutton
Frequently asked questions
Is Sonora, TX tap water safe to drink?
Sonora'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 #522 out of 1067 cities tested in Texas.
What contaminants are in Sonora's water?
Lead was measured at 1.2 ppb (90th percentile). 24 violations are on record.
How is Sonora'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 Sonora?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Sonora's water come from?
Sonora's water is sourced from Groundwater. The city has 1 water system serving approximately 2,766 residents.
What health violations has Sonora's water system had?
Sonora has 2 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. 15 violations remain unresolved.
Is Sonora's groundwater at risk of contamination?
Sonora 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 24 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 Sonora's water compare to other cities?
Sonora ranks #522 out of 1067 cities in Texas (better than 51% of state cities) and #10071 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.
Does Sonora's small water system affect quality?
Sonora's system serves approximately 2,766 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 24 violations on record.