Nicasio Water Quality

Latest water quality information for Nicasio, California

Last update on March 2025

Acceptable water with improvement potential.

Exceeds 0 EPA limits and 6 recommended standards.

Water Provider

nicasio valley ranch mutual

Owner Type

P (Private)

Population Served

Data Sources

2010-2023

Contaminants exceeding EPA limits

What it means: This refers to substances in the water that are found at levels higher than what the EPA allows. The EPA (Environmental Protection Agency) is a U.S. government agency that sets legal limits for harmful contaminants to protect public health. Exceeding these limits means the water may pose health risks based on federal safety standards.

Good news! No contaminants were found to exceed EPA limits.

Contaminants exceeding recommended standards

What it means: This refers to substances in the water that are above health-based guidelines set by organizations such as the World Health Organization (WHO) and the U.S. Environmental Protection Agency (EPA). These standards, while not always legally enforceable, are based on scientific research to protect health. Exceeding them may indicate potential health concerns.

Bromodichloromethane

11.30 ppb

188.3x

Recommended: 0.0600 ppb

Above health-based recommendations

Potential Health Effects

Cancer

Bromoform

0.8000 ppb

1.6x

Recommended: 0.5000 ppb

Above health-based recommendations

Potential Health Effects

Cancer

Chloroform

12.90 ppb

32.2x

Recommended: 0.4000 ppb

Above health-based recommendations

Potential Health Effects

Cancer

Copper

717 ppb

2.4x

Recommended: 300 ppb

Above health-based recommendations

Potential Health Effects

Organ damage

Dibromochloromethane

6.50 ppb

65.0x

Recommended: 0.1000 ppb

Above health-based recommendations

Potential Health Effects

Cancer

Total Thms

31.30 ppb

208.7x

Recommended: 0.1500 ppb

Above health-based recommendations

Potential Health Effects

Cancer

Other Detected Contaminants

Contaminant	Detected Level	EPA Limit	Recommended	Status
Specific Conductivity	510 µmhos/cm	Not established	800 µmhos/cm	Within limits
No additional contaminants detected.

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Carbon Filter

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