Exceeds EPA Limit Nitrate EXCEEDS EPA LIMIT

Nitrate in Gilroy, CA Drinking Water

Nitrate data for Gilroy, California · 67,945 residents · 2 ZIP codes

ZipCheckup's reading of Nitrate in Gilroy, California: the highest detected level is 12 ppb; the EPA limit is 10 mg/L (as nitrogen). Nitrate carries a high health-risk designation.

Water quality records for Gilroy, California show Nitrate detections on file - a finding that places it among the contaminants worth tracking for this area.

12 ppb
Max Level Detected
12 ppb
Average Level
10 mg/L (as nitrogen)
EPA MCL
High
Health Risk
Reverse Osmosis or Ion Exchange
Best Filter Method

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

Nitrate in Gilroy Tap Water

Nitrate has been detected in Gilroy, California drinking water at a maximum level of 12 ppm — 1.2x the EPA MCL.

This analysis covers 67,945 residents across 2 ZIP codes in Gilroy.

Gilroy's overall water quality grade is B (80/100).

Is Nitrate in Gilroy Water Safe?

Nitrate levels in parts of Gilroy exceed the EPA MCL of 10 mg/L (as nitrogen). The EPA requires water systems to take corrective action when this limit is exceeded.

If you live in an affected ZIP code, consider installing a reverse osmosis or ion exchange filter certified under NSF 53 / NSF 58 and testing your water independently.

Nitrate Levels by ZIP Code

ZIP Code Nitrate Level EPA Limit Status
95020 12 ppm 10 mg/L (as nitrogen) Exceeds limit
95021 12 ppm 10 mg/L (as nitrogen) Exceeds limit

Average nitrate level across Gilroy: 12 ppb

Health Effects of Nitrate

  • Methemoglobinemia ("blue baby syndrome") in infants under 6 months
  • Increased risk of colorectal and bladder cancer (long-term)
  • Thyroid disease from chronic exposure
  • Possible reproductive effects

Health risk severity: High. Governed by the National Primary Drinking Water Regulations.

How Nitrate Gets Into Drinking Water

  • Agricultural fertilizer runoff
  • Animal feedlot operations and manure
  • Septic system leachate
  • Urban stormwater and wastewater discharge

What to Do About Nitrate in Gilroy Water

  1. Reverse osmosis is the most effective method for nitrate removal
  2. Ion exchange systems designed for nitrate can also work
  3. Standard carbon filters do NOT remove nitrate
  4. Boiling water increases nitrate concentration — never boil for nitrate

Look for filters certified under NSF 53 / NSF 58 for nitrate removal.

Related

Home → Contaminants → Nitrate → California → Gilroy

How to cite this page

APA ZipCheckup. (2026). Nitrate in Gilroy, CA Drinking Water. https://zipcheckup.com/contaminants/nitrates/gilroy-ca/
BibTeX 
@misc{zipcheckup-contaminants-nitrates-gilroy-ca,
  author = {{ZipCheckup}},
  title  = {{Nitrate in Gilroy, CA Drinking Water}},
  year   = {2026},
  url    = {https://zipcheckup.com/contaminants/nitrates/gilroy-ca/}
}

Data as of July 2026.

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