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San Luis Obispo Water Quality

Latest water quality information for San Luis Obispo, California

Last update on March 2025

Very bad

Unsafe water with serious health risks.

Exceeds 1 EPA limits and 9 recommended standards.

Water Provider
san luis obispo water department
Owner Type
L (Local Government)
Population Served
46,058
Data Sources
2017-2024

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.

Ethylene Dibromide

0.2000 ppb
4.0x
EPA limits: 0.0500 ppb
Above EPA regulatory threshold

Potential Health Effects

Cancer

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

9.20 ppb
153.3x
Recommended: 0.0600 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Bromoform

1.30 ppb
2.6x
Recommended: 0.5000 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Chloroform

20.10 ppb
50.2x
Recommended: 0.4000 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Dibromochloromethane

6.60 ppb
66.0x
Recommended: 0.1000 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Dibromochloropropane

0.1000 ppb
58.8x
Recommended: 0.001700 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Sodium

24.10 ppm
1.2x
Recommended: 20 ppm
Above health-based recommendations

Potential Health Effects

Hypertension

Total Thms

38 ppb
253.3x
Recommended: 0.1500 ppb
Above health-based recommendations

Potential Health Effects

Cancer

Uranium

1.10 ppb
2.6x
Recommended: 0.4300 ppb
Above health-based recommendations

Potential Health Effects

Cancer, kidney damage

Other Detected Contaminants

Contaminant Detected Level EPA Limit Recommended Status
Aluminum 38 ppb 200 ppb 600 ppb Within limits
Calcium 27.10 ppm Not established 80 ppm Within limits
Chloride 20 ppm 250 ppm 250 ppm Within limits
Conductivity 556.60 µS/cm Not established 800 µS/cm Within limits
Fluoride 497.80 ppb 4000 ppb 2000 ppb Within limits
Magnesium 21.20 ppm Not established 30 ppm Within limits
Molybdenum 3.30 ppb Not established 40 ppb Within limits
Nickel 5.30 ppb Not established 70 ppb Within limits
Ph Level 6.40 pH units 8.50 pH units 8.50 pH units Within limits
Potassium 1.50 ppb Not established 5000 ppb Within limits
Specific Conductivity 251.20 µmhos/cm Not established 800 µmhos/cm Within limits
Strontium 310 ppb Not established 1500 ppb Within limits
Sulfate 61.10 ppm 250 ppm 250 ppm Within limits
Total Dissolved Solids 207.90 ppm 500 ppm 500 ppm Within limits
Trichlorofluoromethane 1 ppb Not established 1300 ppb Within limits
Zinc 71.30 ppb 5000 ppb 5000 ppb Within limits
No additional contaminants detected.

How to best protect from water pollution?

Reduce your water pollution exposure in California

Carbon Filter

Carbon filters are effective at removing many common contaminants including chlorine, sediment, volatile organic compounds (VOCs), and improves taste and odor.

Reverse Osmosis

Reverse osmosis systems can remove up to 99% of dissolved contaminants from water including heavy metals, fluoride, nitrates, and arsenic.

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