DES PERES, Texas Tap Water Quality

What this violation means

Total coliform bacteria are themselves usually harmless, but their presence signals that the water distribution system has a vulnerability — typically a cracked pipe, loss of pressure, or back-siphonage — that could allow disease-causing pathogens to enter. Repeated coliform-positive samples trigger mandatory utility investigation.

Recommended precautions

• →If your utility issues a boil-water advisory, boil all drinking and cooking water for at least one minute.
• →Use bottled water until the advisory is lifted.
• →Ice from icemakers and beverages made before the advisory should be discarded.
• →UV light and chlorination both kill coliform bacteria — most home filters do not.

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

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.

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

The EPA regulates total chromium, which includes both trivalent (Cr-3, an essential nutrient) and hexavalent (Cr-6, the carcinogen made famous by the Erin Brockovich case). California has set a separate Cr-6 MCL of 10 ppb; the federal standard does not yet distinguish the two.

Recommended precautions

• →Reverse osmosis effectively removes chromium.
• →Some specialized ion exchange resins target hexavalent chromium specifically.
• →Standard carbon filters do not reliably remove chromium.

What this violation means

Fluoride at the optimal level (~0.7 mg/L) reduces tooth decay, which is why most US utilities add it. The MCL of 4.0 mg/L exists to protect against skeletal fluorosis from naturally high-fluoride groundwater, while the EPA's secondary standard of 2.0 mg/L addresses dental fluorosis in children.

Recommended precautions

• →Reverse osmosis removes fluoride; standard carbon filters do NOT.
• →If your child uses fluoride toothpaste and drinks fluoridated water, supervise brushing to limit ingestion.
• →Bone meal supplements often contain fluoride and should be used cautiously.

What this violation means

Radium-226 and Radium-228 occur naturally in groundwater, particularly in regions with granite or sandstone aquifers. Long-term ingestion increases the risk of bone, sinus, and other cancers because radium concentrates in bone tissue.

Recommended precautions

• →Reverse osmosis and ion exchange (water softeners) remove radium.
• →Boiling does NOT remove radium and may concentrate it.
• →Private well users in radium-rich geology should test every 3–5 years.

What this violation means

Radium-226 and Radium-228 occur naturally in groundwater, particularly in regions with granite or sandstone aquifers. Long-term ingestion increases the risk of bone, sinus, and other cancers because radium concentrates in bone tissue.

Recommended precautions

• →Reverse osmosis and ion exchange (water softeners) remove radium.
• →Boiling does NOT remove radium and may concentrate it.
• →Private well users in radium-rich geology should test every 3–5 years.

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

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

Total coliform bacteria are themselves usually harmless, but their presence signals that the water distribution system has a vulnerability — typically a cracked pipe, loss of pressure, or back-siphonage — that could allow disease-causing pathogens to enter. Repeated coliform-positive samples trigger mandatory utility investigation.

Recommended precautions

• →If your utility issues a boil-water advisory, boil all drinking and cooking water for at least one minute.
• →Use bottled water until the advisory is lifted.
• →Ice from icemakers and beverages made before the advisory should be discarded.
• →UV light and chlorination both kill coliform bacteria — most home filters do not.