Is the mineral level found by government sampling a health hazard for skin?
A common misunderstanding is to assume that any detection of minerals like calcium and magnesium in water means a health risk for sensitive skin. The U.S. Geological Survey data for Harris County's 112CHCT aquifer reports calcium and magnesium concentrations measured in 67 samples from 54 wells. These minerals are naturally occurring and were detected in nearly all samples, with a median concentration of 142 mg/L and a range from 48.1 to 234 mg/L. None of these measurements exceeded federal health-based thresholds. Importantly, these figures do not indicate that your well water has the same levels or that skin irritation is guaranteed.
What does a certified laboratory report on calcium and magnesium show and how should I interpret it?
A certified lab test for your household water will quantify calcium and magnesium concentrations, typically combined as hardness. This number reflects the milligrams per liter (mg/L) of these dissolved minerals. High hardness can sometimes contribute to skin dryness or irritation, especially for sensitive individuals. However, lab results do not diagnose skin conditions. They are a starting point to decide if further water treatment is appropriate. Knowing your water’s exact mineral content is essential before selecting any treatment technology.
Does the government data reveal changes in mineral levels over time that affect sensitive skin?
The groundwater samples in Harris County have been collected over more than a decade, from March 16, 2010, through August 5, 2024. Over this period, the median mineral concentration remained fairly stable within the recorded range. This consistency suggests no significant seasonal or multi-year variation in calcium and magnesium levels in the aquifer. Therefore, skin sensitivity related to these minerals is unlikely to fluctuate dramatically over time based on regional groundwater composition alone.
How many samples constitute the dataset, and what does that mean for interpreting local water quality?
The data includes 67 samples from 54 individual wells ranging in depth from 305 to 1556 feet. This relatively large and diverse set of wells provides a broad picture of the aquifer’s mineral content but does not represent any single household’s water precisely. A smaller number of samples would reduce confidence in the typical range, but here the varied and numerous sources contribute to a reliable regional estimate. For individual water quality, specific testing remains necessary.
What do the terms 'detected,' 'median,' and 'range' tell me about the Harris County groundwater results?
'Detected' means the lab instruments found calcium and magnesium in 66 out of 67 samples, confirming these minerals are consistently present. The 'median' of 142 mg/L is the middle value where half the samples measure above and half below, offering a typical mineral concentration for the area. The 'range' from 48.1 to 234 mg/L reflects variability among wells, affected by local geology and depth. These terms describe the statistical distribution of the data but do not signify regulatory violations or predict individual household water conditions.
The U.S. Geological Survey’s dataset for Harris County’s 112CHCT aquifer covers a large area with many wells sampled between 2010 and 2024. It provides a regional understanding of calcium and magnesium mineral content in groundwater, not a personal water analysis. To address sensitive skin concerns related to mineral content, consider obtaining a certified laboratory test of your own water. When choosing treatment technology, the C-Series Sensitive Skin & Eczema System ships ready to configure with a 32,000 grain capacity designed to reduce mineral-related skin impact, helping households find relief based on documented performance and your water’s specific test results. For more information, see the original government record at the USGS water data site.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2024-08-05. 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 Hardness, Ca, Mg in the 112CHCT aquifer (Harris County): 67 results from 54 wells, median 142.0 mg/L, range 48.1-234.0 mg/L; none above any federal threshold