This system has an open, unresolved health-based violation for Lead and Copper. Check your utility's notification or use bottled water until the violation is resolved.
Lead or copper was detected above the action level at some taps
1 open violation
Act soon▾
A lead violation means the 90th percentile of tap samples exceeded 0.015 mg/L — the action level that triggers mandatory response. Lead risk varies by home: older plumbing and lead service lines concentrate risk. A certified lab test (~$25) tells you your specific exposure. Look for filters certified NSF/ANSI 53 for lead reduction.
This system was not included in federal PFAS monitoring
FYI▾
Should I be concerned?
This system serves fewer than 3,300 people and was not required to participate in EPA UCMR5 testing. Absence of data is not the same as absence of contamination.
Lead risk depends on your home, not just the water system
service line inventory incomplete
Act soon▾
The concern isn't usually the treatment plant — it's pipes inside older homes. No level is considered safe for children under 6.
Should I be worried?
Not necessarily — but if your home was built before 1986, it's worth checking whether you have lead pipes or solder. Run cold water 30 seconds before drinking in the morning.
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A metal that enters water from discharge from petroleum refineries and fire retardant manufacturing, and from erosion of natural deposits.
Why it matters
Long-term exposure above the MCL of 0.006 mg/L may increase blood cholesterol and decrease blood sugar.
What to do
No action needed at typical detection levels.
Arsenic▸
0.0025 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A naturally occurring element found in rock and soil. Gets into drinking water through erosion of natural deposits or runoff from industrial and agricultural sources.
Why it matters
Long-term exposure is linked to increased risk of skin, bladder, and lung cancer. There is no safe level for arsenic — the MCL of 10 µg/L balances health protection with treatment feasibility.
What to do
If your water is near or above the limit, a reverse osmosis filter certified to NSF/ANSI 58 removes over 90% of arsenic. Point-of-use filters at the kitchen tap are effective and affordable.
What the research says
Multiple peer-reviewed studies have found congenital heart defects including atrial septal defects at concentrations as low as 0.0005 mg/L — 20x below the US federal limit.
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A naturally occurring metal found in mineral deposits. Enters water through erosion of natural deposits or discharge from drilling and metal refining operations.
Why it matters
At high levels, barium can cause increased blood pressure. Levels well below the MCL of 2 mg/L are not a health concern.
What to do
No action needed at typical detection levels. Barium is rarely found near its MCL in treated drinking water.
Fluoride▸
0.18 mg/L
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
Naturally occurring mineral, also added to many water systems to prevent tooth decay. The MCL (4 mg/L) is much higher than the typical added amount (0.7 mg/L).
Why it matters
At levels near the MCL, long-term exposure can cause skeletal fluorosis (bone pain and tenderness). The secondary standard of 2 mg/L triggers a required public notice about dental fluorosis risk in children.
What to do
Levels below 2 mg/L are within the range considered safe. If above 2 mg/L, children under 9 may be at risk for dental fluorosis — talk to your pediatric dentist.
What the research says
Multiple peer-reviewed studies have found lower IQ in children and potential thyroid disruption at concentrations as low as 1.5 mg/L — 3x below the US federal limit.
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
A screening test that measures total alpha radiation from all radioactive elements in water — including radium, uranium, and radon.
Why it matters
The MCL of 15 pCi/L protects against long-term cancer risk from radiation exposure.
What to do
No action needed at typical detection levels. If near the MCL, reverse osmosis and ion exchange filters can reduce radioactive contaminants.
Nitrate (as N)▸
Duration
24 mg/L ×2.4
Reference: MCL
Federal Maximum Contaminant Level. The legally enforceable EPA drinking-water standard.
What is it?
Comes from fertilizer runoff, septic systems, and erosion of natural deposits. One of the most common groundwater contaminants in agricultural areas.
Why it matters
Nitrate above 10 mg/L can cause "blue baby syndrome" (methemoglobinemia) in infants under 6 months — it interferes with blood's ability to carry oxygen. Adults can tolerate higher levels.
What to do
If you have an infant on formula and your water is above 5 mg/L, consider using bottled water for formula preparation. Boiling water does NOT remove nitrate — it concentrates it.
What the research says
Multiple peer-reviewed studies have found neural tube defects, preterm birth, and low birth weight at concentrations as low as 5 mg/L — 2x below the US federal limit.
World Health Organization drinking-water guideline. International guidance, not legally enforced in the US.
What is it?
Naturally present in most water sources. Also increases from road salt, water softeners, and natural mineral deposits.
Why it matters
There is no federal MCL for sodium. The WHO suggests a guideline of 200 mg/L for people on sodium-restricted diets. For most people, sodium in water is a small fraction of dietary intake.
What to do
If you're on a sodium-restricted diet and your water is above 20 mg/L, talk to your doctor. For most people, no action needed.
% of limit
Other measurements
These describe characteristics of the water that aren’t health risks at typical levels — mineral content, taste, hardness, and similar.
The following measurements were extracted from this system's Consumer Confidence Report but have been flagged for verification. These values are likely extraction or unit errors and have been removed from the chart above.
Contaminant
Reported Value
Limit
Reason
Hardness
180 mg/L
180 mg/L
Flagged for review
Think this data is correct?
Source: YOKOHL MUTUAL WATER CO Consumer Confidence Report 2022 · Extracted by WaterScore
Measured data
Private Well Risk
Do you have or use a private well? Measured concentrations from nearby private wells sampled within 5 miles.
Details ↓
2 wells
Water Sources
Visalia pumps water from two groundwater wells drawing from the Central Valley aquifer system. Emergency backup sources are available if primary supplies are disrupted.