Government data from the U.S. Geological Survey shows nitrate has been measured in 636 samples from 53 wells ranging in depth from 180 to 2326 feet throughout Bexar County’s 218EDRDA aquifer between December 2010 and June 2026. The median nitrate concentration in these samples is 3.86 milligrams per liter (mg/L), with values ranging from as low as 0.034 to as high as 21.2 mg/L. Of these, 119 samples exceeded the federal health-based maximum contaminant level (MCL) of 10.0 mg/L, a threshold set to limit nitrate due to potential health concerns.
If you read the median and range of nitrate data for Bexar County
As a homeowner, understanding these numbers means your water could have nitrate levels anywhere within a broad range. The median around 3.86 mg/L suggests many samples were well below the federal MCL, but a significant minority exceeded it. This information cannot reveal the nitrate concentration in your specific well or tap water. Instead, it reflects the wider conditions across many wells in the area. Contamination or natural nitrate presence can vary greatly by location and depth, so these figures are a starting point for awareness rather than a direct assessment.
If you receive a certified laboratory nitrate test report for your home water
A certified lab test will provide a precise concentration of nitrate in your water, typically in mg/L. This value shows nitrate levels at the time and place of sampling only. Comparing it to the federal MCL of 10.0 mg/L helps determine if treatment may be warranted to reduce nitrate. Lab reports may also include nitrite, a related compound sometimes measured together. Understanding these figures requires recognizing that a single test is a snapshot, and repeated testing can track changes over time.
If you consider the maintenance rhythm of the Fleck Nitrate & Nitrite (Well) Filter system
This treatment technology ships ready to configure for residential systems and utilizes processes designed to reduce nitrate and nitrite from well water. Routine maintenance mainly involves periodic checks and cleaning or media replacement as recommended by the product documentation. Maintaining proper operation ensures ongoing effectiveness in removing elevated nitrate, aligning with the homeowner’s interest in safe drinking water quality without complicated upkeep.
If you compare public system nitrate records to private well water testing
Public water system records include sampling data from multiple points and times, representing regional water quality conditions but not individual private wells. Private wells can vary substantially due to local geology, land use, and well construction. While public system data may indicate potential nitrate concerns in an area, only direct testing of your private water supply reveals its actual nitrate concentration. Public records are valuable for context but do not replace specific well testing.
If you learn how the Fleck System reduces nitrate in household water
The Fleck Nitrate & Nitrite (Well) Filter employs a filtration process that targets nitrate and nitrite ions, removing them from water before reaching household taps. This technology helps lower nitrate levels to meet safe-use guidelines, aiding in minimizing potential health risks associated with elevated nitrate ingestion. By reducing these compounds, the treated water supports safe consumption and everyday use.
If you distinguish nitrate from other commonly confused water problems
Nitrate is often confused with other water contaminants but differs in origin and effects. Unlike aesthetic or minor mineral issues, nitrate at elevated levels can present specific health concerns, particularly for infants and pregnant women. It is distinct from problems such as iron staining or hardness, which influence taste and appearance without imposing the same health-related thresholds. Understanding this difference guides appropriate testing and treatment decisions.
This summary is based on comprehensive nitrate measurements from groundwater wells across Bexar County’s 218EDRDA aquifer sampled by the U.S. Geological Survey from 2010 through mid-2026. For more detailed data, visit the official government source provided by USGS groundwater monitoring.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2026-06-02. These figures describe groundwater sampled in this area. They are not a test of any individual private well - only a test of that well can establish its own water.
On record: U.S. Geological Survey sampling of Nitrate in the 218EDRDA aquifer (Bexar County): 636 results from 53 wells, median 3.86 mg/L, range 0.034-21.2 mg/L; 119 above a health-based federal MCL (federal MCL 10.0 mg/L)
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