WaterVerge

Is Llano, CA Tap Water Safe to Drink?

Graded B-, with 6 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

845 residents served 3 water systems PWSID: CA1900849
Overall Score
74.1 / 100
Violations
6 active
Last Updated
May 2026
Source
Groundwater
#467 of 694 in California Top 63% nationally
Private
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B-GRADE
Water Quality Grade
74.1/100
waterverge.com
B- 74.1/100

Llano, CA — Water Quality Report

Llano's drinking water received a grade of B- (74.1 out of 100), indicating fair water quality. The city's 3 water systems serve approximately 845 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 16 violations on record, including 3 health-based violations. 6 remain unresolved.

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

What to know about Llano's water

Llano ranks #467 out of 694 cities in California for water quality, placing it below average in the state.

Llano 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, Llano may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

The system has seen 7 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
74.1 out of 100 Grade B-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
27.1/45
C
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 Llano, CA water safe to drink?

Concerns Identified

Llano's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (74.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 845 residents using groundwater (wells).

6
Active Violations
0.0 ppb
Lead (90th %ile)
10 events
Disaster History

Recent water quality updates for Llano

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Llano's water quality assessment. Grade: B- (74.1/100).

Violation
6 drinking water violations recorded

3 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Disaster
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-3592). Flood event — may have impacted local water infrastructure.

Disaster
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES

Federal disaster declaration (FEMA DR-4683). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Key contaminant findings

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

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

Well within EPA limits.

Violation history

Llano's water system has 16 total violations on record, including 3 health-based violations. 6 remain unresolved. 7 violations were issued in the last 5 years.

RPTTTMONMR
Most recent violations:
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open

Flood & environmental risk

Los Angeles County has experienced 10 federally declared disasters since 1980. 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 Rock C Nr Valyermo.

SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-3592
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA DR-4683
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA DR-3591

Where does Llano's water come from?

Llano's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 845 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 Rock C Nr Valyermo (river).

What Llano residents can do

Install a water filter

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

Llano'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

16
Total violations
3
Health-based
6
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

16 Total
6 Active
3 Health-based
10 Resolved
Violations by category
Total Coliform Rule
8
Lead and Copper Rule Revisions
6
Revised Total Coliform Rule
1
Lead and Copper Rule
1
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Jul 2023 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Jul 2023
Oct 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 2011
Sep 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2011
Aug 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2011
Jul 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 2011
Feb 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Feb 2011
Feb 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Feb 2011
Jan 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jan 2011
Jan 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jan 2011
Jul 1993 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2003
Environmental Risk

Flood & disaster history

10
Declared disasters
Mar 2023
Most recent
Flood
Most common type

Los Angeles County has experienced 10 federally declared disasters since 1980. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Mar 2023
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #3592
Jan 2023
SEVERE WINTER STORMS, FLOODING, LANDSLIDES, AND MUDSLIDES
Flood FEMA #4683
Jan 2023
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #3591
Mar 2017
SEVERE WINTER STORMS, FLOODING, AND MUDSLIDES
Flood FEMA #4305
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3248
Feb 1993
SEVERE WINTER STORM, MUD & LAND SLIDES, & FLOODING
Flood FEMA #979

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 increased by 6.8 ppb from 2015 (0.0 ppb) to 2024 (6.8 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Private
Population Served
845
Water Systems
3
Source breakdown
Groundwater
2
Purchased Groundwater
1
Water Source

Where Llano's water comes from

Groundwater

Llano'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 private ownership and serves approximately 845 people through 3 water systems.

Local Hydrology

Water bodies near Llano

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

Big Rock C Nr Valyermo
river
Infrastructure

Water systems serving Llano

System Name PWSID Population Source
LLANO DEL RIO WATER COMPANY CA1900849 545 GW
LLANO MUTUAL WATER COMPANY CA1900303 245 GWP
LITTLE BALDY WATER CA1900158 55 GW
Regional Comparison

How Llano compares

Full California rankings →

Llano's score of 74.1/100 is above the average of 57/100 among major California cities. It outscores 7 of 10 nearby cities.

Llano (this city)
74.1
Oakland
77.9
San Diego
39.7
Sacramento
31.2
California avg
57
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Frequently asked questions

Is Llano, CA tap water safe to drink?

Llano's water quality earned a grade of B- (74.1/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #467 out of 694 cities tested in California.

What contaminants are in Llano's water?

Lead was measured at 0.0 ppb (90th percentile). 16 violations are on record.

How is Llano'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 Llano?

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

Where does Llano's water come from?

Llano's water is sourced from Groundwater. The city has 3 water systems serving approximately 845 residents.

What health violations has Llano's water system had?

Llano has 3 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 6 violations remain unresolved.

Is Llano's groundwater at risk of contamination?

Llano 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 16 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 Llano's water compare to other cities?

Llano ranks #467 out of 694 cities in California (better than 33% of state cities) and #9938 out of 15744 cities nationally (37th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.