Mettler Valley Mutual
EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the California State Water Resources Control Board, as well as information from the U.S. EPA Enforcement and Compliance History database (ECHO). For the latest quarter assessed by the U.S. EPA (January 2021 - March 2021), tap water provided by this water utility was in compliance with federal health-based drinking water standards.
Utility Details
- Los Angeles County, California
- Serves: 100
- Data available: 2014-2019
- Source: Groundwater
Contaminants Detected
5
EXCEED
EWG HEALTH
GUIDELINES
8 Total Contaminants
- Legal does not necessarily equal safe. Getting a passing grade from the federal government does not mean the water meets the latest health guidelines.
- Legal limits for contaminants in tap water have not been updated in almost 20 years.
- The best way to ensure clean tap water is to keep pollution out of source water in the first place.
Looking for a countertop water filter?
Find out which filters earned EWG's recommendation
See the guideContaminants Detected
Arsenic
more aboutthis contaminant
Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.
Arsenic was found at 3,527 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.004 ppb for arsenic was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources
![agriculture icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-agriculture.png)
Agriculture
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Chromium (hexavalent)
Potential Effect: cancer68x EWG'S HEALTH GUIDELINEChromium (hexavalent)
more aboutthis contaminant
Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).
Chromium (hexavalent) was found at 68 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Manganese
Potential Effect: harm to the brain and nervous system6x EWG'S HEALTH GUIDELINEManganese
more aboutthis contaminant
Manganese is a naturally occurring element that is common in food and drinking water. Excessive manganese exposures may impair children's attention, memory and intellectual capacity. Click here to read more about manganese.
Manganese was found at 6 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 100 ppb for manganese was defined by the state of Minnesota as a health risk limit, the concentration of a contaminant that can be consumed with little or no risk to health. This health guideline protects against harm to the brain and nervous system.
Pollution Sources
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Nitrate
Potential Effect: cancer24x EWG'S HEALTH GUIDELINENitrate
more aboutthis contaminant
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.
Nitrate was found at 24 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Health Risks
The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.
Pollution Sources
![agriculture icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-agriculture.png)
Agriculture
![urban area icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-runoff-sprawl.png)
Runoff & Sprawl
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Uranium
Potential Effect: cancer18x EWG'S HEALTH GUIDELINEUranium
more aboutthis contaminant
Uranium is a known human carcinogen. The federal legal limit for uranium is set at 30 micrograms per liter (corresponding to parts per billion), but utilities can also report uranium in picocuries per liter (pCi/L), which is a measure of radioactivity in water. EWG translated all uranium results to pCi/L using a conversion factor developed by the EPA. With this conversion approach, the limit of 30 ppb corresponds to 20 pCi/L. Drinking water with this much uranium would cause more than 4.6 cancer cases in a population of 100,000. California set a public health goal for uranium of 0.43 pCi/L.
Uranium was found at 18 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
pCi/L = picocuries per liter
Health Risks
The EWG Health Guideline of 0.43 pCi/L for uranium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. Three most common uranium isotopes are U-234, U-235 and U-238. All isotopes of uranium are radioactive, and the total radioactivity depends on the ratio of isotopes. This health guideline protects against cancer.
Pollution Sources
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Includes chemicals detected in 2017-2019 for which annual utility averages exceeded the federal Maximum Contaminant Level (MCL); chemicals detected in 2017-2019 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority; radiological contaminants detected between 2014 and 2019.
Barium is a mineral present in rocks, soil and water. High concentrations of barium in drinking water increase the risk of cardiovascular disease and hypertension.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 700 ppb for barium was defined by EWG as benchmark that protects against harm to the kidneys and the cardiovascular system.
Pollution Sources
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Chromium (total)
more aboutthis contaminant
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources
![industry icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-industry.png)
Industry
![naturally occuring icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-naturally-occuring.png)
Naturally Occurring
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
![ion exchange icon](https://static.ewg.org/reports/2017/tap-water/img/IonExchange_Icon.png)
Ion Exchange
Fluoride
more aboutthis contaminant
Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Pollution Sources
![water treatment icon](https://static.ewg.org/reports/2017/tap-water/img/pollution-source-treatment-byproducts.png)
Treatment Byproducts
Filtering Options
![reverse osmosis icon](https://static.ewg.org/reports/2017/tap-water/img/Osmosis-Icon.png)
Reverse Osmosis
Includes chemicals detected in 2017-2019 for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authori.
Other Contaminants Tested
✕Mettler Valley Mutual compliance with legally mandated federal standards:
- From April 2019 to March 2021, Mettler Valley Mutual complied with health-based drinking water standards.
- 9 QUARTERSin violation of any federal drinking water standard from April 2019 to March 2021
- Over the last 3 years this water utility has spent 1 QUARTERin significant violation of federal drinking water standards
Information in this section on Mettler Valley Mutual comes from the U.S. EPA Enforcement and Compliance History Online database (ECHO).
LEARN MORE ABOUT THIS UTILITYWater Filters That Can Reduce Contaminant Levels
Contaminant | Activated Carbon | Reverse Osmosis | Ion Exchange |
CONTAMINANTS ABOVE HEALTH GUIDELINES | |||
Arsenic | ✔ | ✔ | |
Chromium (hexavalent) | ✔ | ✔ | |
Manganese | ✔ | ||
Nitrate | ✔ | ✔ | |
Uranium, combined (pCi/L) | ✔ | ✔ | |
OTHER CONTAMINANTS DETECTED | |||
Barium | ✔ | ✔ | |
Chromium (total) | ✔ | ✔ | |
Fluoride | ✔ |
Take Action
Contact Your Local Official
One of the best ways to push for cleaner water is to hold accountable the elected officials who have a say in water quality – from city hall and the state legislature to Congress all the way to the Oval Office – by asking questions and demanding answers.
LEARN MOREFilter Out Contaminants
Check out our recommendations for filters to protect your water against the detected contaminants.
EWG’S WATER FILTER GUIDE