Gardena, California

Gardena, California Gardena, California

What is the Water Quality in Gardena, California?

[Update: June 10, 2023]

Compared to other US cities, Gardena water quality ranks in the middle range for contamination excluding Lead.

Most of their 27 contaminants have cancer-causing attributes.

  • Arsenic is at particularly high levels: 97x health guidelines.

Let’s look closer at what’s in Gardena water.

What’s in Gardena water?

Here are the top 5 chemical compounds in your water and what health issues they can potentially cause:

  1. Arsenic – Potential effect: Cancer
  2. Bromodichloromethane – Potential effect: Cancer
  3. Chloroform – Potential effect: Cancer
  4. Haloacetic acids (HAA5) – Potential effect: Cancer
  5. Total trihalomethanes – Potential effect: Cancer

These are five of the 27 contaminants analyzed by the Environmental Working Group (

12 of these contaminants are rated as exceeding EWG Health Guidelines.

Does Gardena have Lead contamination?

Yes, Gardena has lead in its water. The most recent Lead samples collected from 2014 through 2016 showed concentrations up to 1.0 parts per billion.

The legal limit for lead is 15 parts per billion. Being well-below this level is a good thing.

Concentrations between 3.8 ppb and 15 ppb put a formula-fed baby at risk of elevated blood lead levels. Read more about the symptoms of Lead in water.

There is no safe level of lead for humans.

The good news is that 99.99% of the lead can be filtered out.

See the What Can You Do? section below for all of the contaminants you can filter out and how to do it.

Where does Gardena’s water come from?

Gardena’s water comes from the Lower Dominguez Channel watershed.

5 of the 7 assessed water sources in the Lower Dominguez Channel watershed are in Impaired or Unknown condition. These include:

  • Dominguez Channel
  • Los Angeles Harbor
  • Torrance Carson Channel

Ideally, a water source would be rated in Good condition. Del Amo Channel and Los Angeles Project Number 5246 are in Good condition.

Learn more from How’s My Waterway

See below for what you can do to improve Gardena’s water.

Conclusion – What Can You Do?

Information about water quality in Gardena can be surprising.

But there are things you can do in your home to clean up your water.

  1. Test Your Water using Varify Home Test Kits or similar.
  2. To Remove Lead and Other Contaminants In Your Home:
  • Use Activated Carbon filters to remove most contaminants in your drinking water.
    • Faucet-mount filters work better than pitchers.
    • PUR and Brita are low-cost and effective.
Brita Lead Filtration
Brita Faucet Mount – Amazon
  • To filter out even more contaminants in your whole house, consider a Reverse Osmosis water filtration system for your home.
    • These are more expensive than pitchers to purchase, but can be more effective.
    • They have the benefit of filtering out heavy hitters like:
      • Arsenic
      • Barium
      • Bromide
      • Bromoform
      • Chloroform
      • Fluoride
      • Haloacetic acids – byproduct of chlorination*
      • Hexavalent chromium – carcinogenic
      • Molybdenum
      • Strontium – can affect bone growth in children.
      • Total trihalomethanes – byproduct of chlorination*
      • Uranium
    • Our recommendation: APEC Reverse Osmosis Systems
Reverse Osmosis Systems
APEC system – Amazon

*Chlorination is an effective method of disinfecting/treating drinking water. You can then use a water filter to reduce the effects of chlorination byproducts to get the safest, cleanest water possible.

In Your Community:

Contact your local government officials and put pressure on them to invest in cleaner waterways and upgraded city water filtration and treatment.

Go to: to find contact information for your local officials.

Water Quality in Other California Cities

California Water Quality Page

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