FRESNO, California Tap Water Quality

What this violation means

Uranium in drinking water is both a chemical toxin (kidney damage) and a radiological hazard (increased cancer risk). It's most commonly found in groundwater near uranium ore deposits or former mining activity in the Western US.

Recommended precautions

• →Reverse osmosis is the gold standard for removing uranium.
• →Ion exchange systems work but must be sized correctly for uranium.
• →If you live near former mining sites, test for uranium even if not required.

What this violation means

Nitrate contamination is most acute in agricultural regions where fertilizer and animal waste leach into groundwater. The immediate risk is to formula-fed infants under 6 months — high nitrate levels prevent their blood from carrying oxygen, causing 'blue baby syndrome.' Pregnant women should also avoid high-nitrate water.

Recommended precautions

• →Never give untreated high-nitrate water to infants — use bottled water for formula.
• →Boiling does NOT remove nitrate. Boiling concentrates it.
• →Reverse osmosis, ion exchange, or distillation are the only effective home treatments.
• →Private well owners in farming areas should test annually for nitrate.

What this violation means

Lead is a potent neurotoxin with no safe exposure level. In drinking water it primarily enters via corroded lead service lines, lead-soldered copper pipes, and brass fixtures. Children under 6 and pregnant women face the highest risk because lead disrupts developing nervous and skeletal systems.

Recommended precautions

• →Run cold tap water 30–120 seconds before drinking or cooking, especially after the tap has been unused for hours.
• →Never cook with hot tap water — heat increases lead leaching from pipes.
• →Use an NSF/ANSI 53 certified filter for lead removal (carbon block or reverse osmosis).
• →If you have children, get blood lead levels tested by your pediatrician.

What this violation means

Haloacetic Acids (HAA5) are the second major group of disinfection byproducts after TTHMs. They form by the same mechanism — chlorine reacting with organic matter — and pose similar long-term cancer risks. Utilities are required to test quarterly at distribution-system locations to track HAA5 levels.

Recommended precautions

• →Activated carbon filtration removes most HAA5.
• →Reverse osmosis is highly effective.
• →Unlike TTHMs, HAA5 do not significantly off-gas. Use treatment rather than aeration.
• →Long-term ingestion is the primary concern, not short-term skin contact.

What this violation means

Total Trihalomethanes (TTHMs) form when chlorine reacts with naturally occurring organic matter — leaves, soil, algae — in source water. They are among the most commonly reported violations because utilities pulling from surface water (rivers, lakes, reservoirs) struggle to balance disinfection with byproduct formation. Long-term exposure has been linked to bladder cancer and adverse pregnancy outcomes.

Recommended precautions

• →Activated carbon filters (pitcher, faucet, or under-sink) effectively reduce TTHMs.
• →Letting water sit uncovered allows TTHMs to off-gas — leave a pitcher in the fridge for several hours.
• →Shower with the bathroom fan on; TTHMs can volatilize into the air during hot showers.
• →Boiling reduces TTHMs through volatilization, but only after extended boiling.