Whole-Home Drinking Water Considerations in St. Francois County for Farmington Residents

Seasonal and Multi-Year Variation in Farmington's Public Water System Data

The public water system serving Farmington, identified as MO4010270, is supplied by groundwater and its water quality data encompasses multiple years, with the latest lead sampling conducted on December 31, 2024. Over multiple years, 46 samples have been logged, with 39 noted as health-based. This spread over time helps show general trends rather than one-time spikes or drops in constituent levels.

Understanding 'Detected', 'Median', and 'Range' in Sampling Results

Water quality reports from the Farmington public water system show a lead concentration at the 90th percentile of 0.00482 mg/L. It is important to clarify that this figure reflects lead measured within the distribution system plumbing, not the source groundwater. Terms such as 'detected' indicate an instrument found a measurable concentration, while 'median' indicates the middle value of all measurements collected. The 'range' spans from the lowest to the highest detected value across samples and locations. None of these descriptors alone determine safety or compliance.

Distinguishing Aesthetic Secondary Standards from Health-Based Limits for Drinking Water

Federal standards include aesthetic limits that relate to taste, staining, or corrosivity rather than health risks. These differ from health-based limits, which are enforceable and designed to protect consumers. In Farmington’s water system record, health-based violations have been indicated in some measures, but aesthetic standards such as chloride or total dissolved solids (TDS) are not health safety benchmarks. Recognizing this distinction avoids conflating taste or appearance concerns with health hazards.

Interpreting Median and Range Values for Homeowners in Farmington

For a homeowner considering water treatment options, the median lead level of approximately 0.00482 mg/L in plumbing samples suggests relatively low lead presence in the system's distribution network. However, individual homes may vary significantly depending on household plumbing materials. This median and the range of results from multiple sampling points illustrate a general system profile but cannot specify a home's exact water quality without direct testing of that premise.

Sample Size and Source Diversity Behind Farmington’s Water Quality Figures

The data reflects extensive sampling: 46 detailed entries with 39 classified as health-focused by the EPA. These samples come from multiple points throughout the system's 6,255 connections serving over 18,000 residents. Nevertheless, a finite number of samples and a fixed geographic scope mean extrapolations to individual homes come with uncertainty. Variability in plumbing and point-of-use conditions necessitates specific household testing to confirm local water characteristics.

Making Regional Comparisons Without Overinterpreting Data

Farmington’s public water system uses groundwater sources with treatment process codes 380, 421, and 460, which apply to this system’s approach but differ from treatment codes used in neighboring counties. Comparing lead concentrations or health-based violation counts across regions requires careful attention to differences in source water, treatment methods, sampling frequency, and plumbing infrastructure. These factors influence data interpretation and suitability of treatment approaches for each area.

For households in Farmington weighing technical approaches to whole-home drinking water treatment, the Pentair Whole-Home + Drinking Combo System offers a documented solution capable of addressing the range of constituents reflected in local water quality profiles. With a grain capacity of 32,000, it ships ready to configure for home use, meeting typical residential demand while accommodating regional variations documented by public sampling records.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2024-12-31. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA SDWIS record for FARMINGTON PWS (MO4010270), groundwater supply, serving 18217 people: 39 health-based violations of 46 total; lead 90th percentile 0.00482 mg/L