Exceeds EPA Limit Nitrate EXCEEDS EPA LIMIT

Nitrate in Tarzana, CA Drinking Water

Nitrate data for Tarzana, California · 30,809 residents · 2 ZIP codes

For residents of Tarzana, California, Nitrate has appeared in public water supply sampling data.

10 mg/L (as nitrogen)
EPA MCL
28
EPA Violations
High
Health Risk
Reverse Osmosis or Ion Exchange
Best Filter Method

Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-06-04

Nitrate in Tarzana Tap Water

Tarzana, California has 28 EPA violations related to nitrate in drinking water.

This analysis covers 30,809 residents across 2 ZIP codes in Tarzana.

Tarzana's overall water quality grade is D (52/100).

Is Nitrate in Tarzana Water Safe?

Nitrate levels in parts of Tarzana 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.

EPA Violations for Nitrate in Tarzana

Date Violation Type Status ZIP Code
2025-07-01 Nitrate-Nitrite (Open) Open 91356
2025-07-01 Nitrate-Nitrite (Open) Open 91357
2025-01-01 Nitrate-Nitrite (Open) Open 91356
2025-01-01 Nitrate-Nitrite (Open) Open 91357
2024-10-01 Nitrate-Nitrite (Open) Open 91356
2024-10-01 Nitrate-Nitrite (Open) Open 91357
2024-07-01 Nitrate-Nitrite (Known) Known 91356
2024-07-01 Nitrate-Nitrite (Known) Known 91357
2024-04-01 Nitrate-Nitrite (Known) Known 91356
2024-04-01 Nitrate-Nitrite (Known) Known 91357
2024-01-01 Nitrate-Nitrite (Known) Known 91356
2024-01-01 Nitrate-Nitrite (Known) Known 91357
2023-10-01 Nitrate-Nitrite (Known) Known 91356
2023-10-01 Nitrate-Nitrite (Known) Known 91357
2023-07-01 Nitrate-Nitrite (Known) Known 91356
2023-07-01 Nitrate-Nitrite (Known) Known 91357
2023-04-01 Nitrate-Nitrite (Known) Known 91356
2023-04-01 Nitrate-Nitrite (Known) Known 91357
2023-01-01 Nitrate-Nitrite (Known) Known 91356
2023-01-01 Nitrate-Nitrite (Known) Known 91357
... 8 more violations

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 Tarzana 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.

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