If you draw water from a private well in Fairfax County’s aquifer 220JRSC, you may notice changes in water clarity or taste that lead you to consider total well water treatment. Households in this region often believe these water issues are caused by contaminants common elsewhere, but local data provide a clearer perspective to help decide on proper treatment sizing.
Belief: The Problem Is the Same as Hardness or Iron Issues Found in Other Wells
Many homeowners assume their total well water problems are due to typical hardness or iron. However, Fairfax County’s aquifer 220JRSC sampling reveals chloride presence ranging from 4.97 to 180.0 mg/L with a median of 120.0 mg/L, detected consistently across multiple wells 82 to 120 feet deep. This differs from hardness or iron concerns and indicates different water chemistry considerations for treatment.
Belief: Constituents Like Chloride Enter Groundwater from Surface Contamination
In Fairfax County, chloride in the 220JRSC aquifer typically originates from natural mineral dissolution and historical land use rather than direct surface spills. Understanding this source helps clarify that total well water issues here reflect aquifer characteristics rather than recent pollution events.
Belief: Water Quality at My Well Is Constant Over Time
The USGS data collected between August 2011 and September 2025 from two wells show variations in chloride levels but stable detection, indicating some seasonal or multi-year fluctuation without disappearance. This long-term record supports that total well water treatment needs consider potential variation in constituent levels, not just a single test snapshot.
Belief: Quick Testing at Home Can Confirm Water Quality Problems Accurately
While home tests can show general water qualities, accurately sizing treatment requires laboratory analysis of your well water for constituents like chloride. The regional government sampling reflects average conditions but does not substitute for your well’s specific test results, which are needed to align treatment capacity properly.
Belief: Any Total Well Water Treatment Equipment Works Equally Well
The documented effective option for Fairfax County’s total well water issues is the Pentair Total Well Chlorination System, a solution rated for up to 32,000 grain capacity. This system neutralizes constituents typically found in the local aquifer water, ensuring tailored treatment that addresses the specific conditions indicated by the regional sampling.
When sizing a total well water treatment solution for your Fairfax County home, begin by collecting detailed lab analysis of your well water. Then use the regional USGS sampling data as a contextual baseline to select a system like the Pentair Total Well Chlorination System. This approach ensures you address your household’s water needs without over- or under-sizing equipment, leading to more effective and efficient water quality management at the tap.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2025-09-10. 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 Chloride in the 220JRSC aquifer (Fairfax County): 5 results from 2 wells, median 120.0 mg/L, range 4.97-180.0 mg/L; none above any federal threshold