How much copper is in Los Osos water?

The maximum detected level of copper in Los Osos water is 0.86 ppb. The EPA limit is 1.3 mg/L (action level). See the ZIP code table above for area-specific levels.

Detected Copper

Copper in Los Osos, CA Drinking Water

Q: Is copper in Los Osos water safe?

Copper was detected in Los Osos water at 0.86 ppb, below the EPA limit of 1.3 mg/L (action level). Check ZIP-level data on this page for your specific area.

Copper data for Los Osos, California · 15,085 residents · 2 ZIP codes

ZipCheckup's reading of Copper in Los Osos, California: the highest detected level is 0.86 ppb; the EPA limit is 1.3 mg/L (action level). Copper carries a moderate health-risk designation.

Copper is regulated under the Safe Drinking Water Act because of its potential health effects at elevated concentrations; for residents of Los Osos, California, the relevant fact is that it has shown up in recent EPA compliance samples - point-of-use filtration is one option residents research, alongside reviewing the utility's published treatment data.

0.86 ppb

Max Level Detected

0.86 ppb

Average Level

1.3 mg/L (action level)

EPA action level

Moderate

Health Risk

Reverse Osmosis or NSF 53 Carbon Block

Best Filter Method

Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-07-13

Copper in Los Osos Tap Water

Copper has been detected in Los Osos, California drinking water at a maximum level of 0.86 ppm — below the EPA action level of 1.3 mg/L (action level).

This analysis covers 15,085 residents across 2 ZIP codes in Los Osos.

Los Osos's overall water quality grade is B (81/100).

Is Copper in Los Osos Water Safe?

Copper was detected in Los Osos water but currently falls within EPA limits. However, some health organizations argue the EPA action level may not be protective enough.

If you are concerned, a reverse osmosis or nsf 53 carbon block filter can reduce copper levels further.

Copper Levels by ZIP Code

ZIP Code	Copper Level	EPA Limit	Status
93402	0.86 ppm	1.3 mg/L (action level)	OK
93412	0.86 ppm	1.3 mg/L (action level)	OK

Average copper level across Los Osos: 0.86 ppb

Health Effects of Copper

Nausea, vomiting, and diarrhea (short-term, high levels)
Liver and kidney damage (long-term)
Particularly dangerous for people with Wilson's disease
Infants are more sensitive than adults

Health risk severity: Moderate. Governed by the Lead and Copper Rule.

How Copper Gets Into Drinking Water

Corrosion of copper household plumbing
Acidic (low pH) water accelerates copper leaching
New copper pipes leach more than aged ones
Mining and industrial discharge (rare for tap water)

What to Do About Copper in Los Osos Water

Run water for 30-60 seconds before use (flushes stagnant water)
Install an NSF 53 or NSF 58 certified filter
If pH is low, consider a whole-home acid neutralizer
Test first-draw morning water to check actual copper levels

Look for filters certified under NSF 53 for copper removal.

Home → Contaminants → Copper → California → Los Osos

How to cite this page

APA ZipCheckup. (2026). Copper in Los Osos, CA Drinking Water. https://zipcheckup.com/contaminants/copper/los-osos-ca/

BibTeX

@misc{zipcheckup-contaminants-copper-los-osos-ca,
  author = {{ZipCheckup}},
  title  = {{Copper in Los Osos, CA Drinking Water}},
  year   = {2026},
  url    = {https://zipcheckup.com/contaminants/copper/los-osos-ca/}
}

Data as of July 2026.