Serving roughly 6,494 people in Madera County, California.
Data current as of July 2026
🔍Straight from EPA
🧪Real Lab Results
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Results for MADERA VALLEY WATER COMPANY
1 water provider directly on file, serving roughly 6,494 people in Madera County, California.
Quick answer: MADERA VALLEY WATER COMPANY has no violations on file and no single reading stands out against its peers (311 other providers in this area). It serves roughly 6,494 people, and the full breakdown below reflects everything EPA and California have on record for it.
Lead Summary
Aggressive Index
Langelier Index (pH(s))
Magnesium
Potassium
Sodium
Calcium
Alkalinity, Total
Alkalinity, Bicarbonate
Hardness, Total (ASCACO3)
TDS
Chloride
Sulfate
Fluoride
Nitrate-Nitrite
Nitrate
Turbidity
Gross Alpha Particle Activity
pH
Iron
Manganese
Chromium, Hex
Barium
Arsenic
Copper, Free
Zinc
Conductivity (at 25°C)
Color
Utility MADERA VALLEY WATER COMPANYPopulation served 6,494Owner Private
No violations on file
Contaminants found
Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0 mg/L (ppm)
12/31/2023
Iron
Detected: 66 UG/L (ppb)
6/2/2025
Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.
Manganese
Detected: 42 UG/L (ppb)
5/21/2025
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Chromium, Hex
Detected: 1.6 UG/L (ppb)
5/21/2025
Barium
Detected: 110 UG/L (ppb)
5/21/2025
Arsenic
Detected: 8.2 UG/L (ppb)
9/22/2025
Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.
Copper, Free
Detected: 8.2 UG/L (ppb)
5/21/2025
Zinc
Detected: 78 UG/L (ppb)
5/6/2025
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Chloride
Detected: 19 MG/L (ppm)
5/21/2025
Sulfate
Detected: 3 MG/L (ppm)
5/21/2025
Fluoride
Detected: 0.18 MG/L (ppm)
5/21/2025
Often added deliberately for dental health; can also occur naturally.
Nitrate-Nitrite
Detected: 4.1 MG/L (ppm)
5/21/2025
Nitrate
Detected: 4.1 MG/L (ppm)
5/21/2025
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Minerals
Everyday minerals that mainly affect taste and water hardness
Magnesium
Detected: 5.3 MG/L (ppm)
5/21/2025
Potassium
Detected: 2.4 MG/L (ppm)
5/21/2025
Sodium
Detected: 23 MG/L (ppm)
5/21/2025
Calcium
Detected: 15 MG/L (ppm)
5/21/2025
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
Langelier Index (pH(s))
Detected: -1.4 LANG
5/21/2025
Hardness, Total (ASCACO3)
Detected: 61 MG/L (ppm)
5/21/2025
Gross Alpha Particle Activity
Detected: 1.32 PCI/L
1/8/2025
pH
Detected: 7.3 PH
5/21/2025
A measure of how acidic or basic the water is (7 is neutral). Affects taste and plumbing, not a direct health measure.
Calculated Parameters
Values worked out mathematically from other test results, not measured directly
Alkalinity, Bicarbonate
Detected: 61 MG/L (ppm)
5/21/2025
Other
Additional substances tested that don't fit neatly into the categories above
Aggressive Index
Detected: 10.7 AGGR
5/21/2025
Alkalinity, Total
Detected: 61 MG/L (ppm)
5/21/2025
TDS
Detected: 210 MG/L (ppm)
5/21/2025
Turbidity
Detected: 2.1 NTU
5/21/2025
A measure of water cloudiness from suspended particles.
Conductivity (at 25°C)
Detected: 230 UMHO/CM
5/21/2025
Color
Detected: 5 UNITS
5/21/2025
Filtration considerations: See the table below for how whole-house carbon, under-sink reverse osmosis, and under-sink carbon systems compare against what's actually on file here. These are general system types, not a specific product recommendation.