Modesto, California

What is the Water Quality in Modesto, California?

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

Most of their 41 contaminants have cancer-causing attributes.

• Arsenic is at extremely high levels: 288x health guidelines.
• Haloacetic acids (HAA5) are at extremely high levels: 240x health guidelines.
• Haloacetic acids (HAA9) are at extremely high levels: 335x health guidelines.
  • These are both byproducts of the chlorine treatment process most water supplies go through.

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

What’s in Modesto water?

Here are the top 7 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 and HAA9) – Potential effect: Cancer
5. Hexavalent Chromium – Potential effect: Cancer
6. Total trihalomethanes – Potential effect: Cancer
7. Uranium – Potential effect: Cancer

These are seven of the 41 contaminants analyzed by the Environmental Working Group (ewg.org).

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

Does Modesto have Lead contamination?

No, Modesto does not have lead in its water. The most recent Lead samples collected in 2019 showed concentrations of 0.0 parts per billion (ppb).

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 removed.

See the What Can You Do? section below to learn how to filter out contaminants.

Where does Modesto’s water come from?

Modesto’s water comes from the Town of Riverdale Park – Tuolumne River watershed.

All 3 EPA assessed water sources in the Town of Riverdale Park – Tuolumne River watershed are in Impaired or Unknown condition. These include:

• Jacobson Drain – Unknown
• Lateral Drain 5 – Unknown
• Lower Tuolumne River – Impaired. Don Pedro Reservoir to San Joaquin River.

Ideally, a water source would be rated in Good condition.

Whether a water source is in Impaired or Good condition refers to the quality of these uses:

1. Drinking Water
2. Aquatic Life
3. Fish and Shellfish Consumption
4. Recreation

Learn more from How’s My Waterway

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

What Can You Do?

Information about water quality in Modesto can be surprising.

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

To Remove Lead and Other Contaminants In Your Home:

There is one solution that beats Brita, PUR, and some whole house systems.

• It costs less per gallon.
• Needs fewer filter changes.
• And it doesn’t make your water taste weird.

• Use Berkey filters with activated carbon to filter out at least 86% of contaminants in your drinking water. (Berkey Light and Travel Berkey are the only types available in California.)
  • Berkey filters can also remove up to 99.99% of any Lead in Modesto water.
  • Brita can filter 21 contaminants (51.2%) and Lead depending on the filter.
  • Note: We may receive a commission if you decide to purchase filters through links on this page.
• To filter out 35 of the 41 contaminants in your whole house (85.4%), 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:
    • 1,4-Dioxane
    • Aluminum
    • Arsenic – health effects in water
    • Barium
    • Bromodichloromethane
    • Bromoform
    • Chloroform – side effects
    • Chromium (total)
    • DBCP
    • Dibromoacetic acid
    • Dibromochloromethane
    • Dichloroacetic acid
    • Fluoride
    • Haloacetic acids – chlorination byproduct*
    • Hexavalent chromium – health effects
    • Molybdenum
    • Monochloroacetic acid
    • Nitrate
    • Nitrite
    • PFBS
    • PFHXS
    • PFOS
    • Radium
    • Strontium
    • Total trihalomethanes – byproduct of chlorination*
    • Trichloroacetic acid
    • Trichloroethylene
    • Uranium

*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: http://www.modestogov.com/ to find contact information for your local officials.

Water Quality in Other California Cities

California Water Quality Page