The public water system serving Kansas City in Johnson County, known as Water District #1 of Johnson County, reports no detection of 1,4-dioxane above the federal reporting threshold in tests from 2013 to 2015. This means that throughout the sampling period, no measurement surpassed 0.07 micrograms per liter (µg/L), equivalent to parts per billion (ppb).
Why a Low-Level Detection Is Reported to Three Decimal Places and What Precision Means Here
The reported reporting level of 0.07 µg/L for 1,4-dioxane represents the lowest concentration that the federal testing methods reliably distinguish. Measurements below this are considered nondetects, not zero concentrations. Reporting to three decimal places allows detection of very low levels, helping scientists understand trace presence in the environment rather than indicating a direct health concern.
How Landfill Leachate, Degreasing Sites and Consumer Products Each Contribute to the Record
1,4-dioxane is a cyclic ether commonly used as a stabilizer in solvents and found as a byproduct in certain consumer products. It can enter water supplies from historic industrial sites, such as former degreasing locations, and from landfill leachate. These diffuse sources contribute to low-level detections in surface water that feeds large water systems like the one in Johnson County.
What Changes for a Large Household, a Second Home, or a Seasonal Property
A household’s water use and occupancy patterns can influence its exposure to trace constituents like 1,4-dioxane detected at very low levels in the community water supply. Larger families or those with second homes on the same system may have higher overall water consumption, but the concentration of dioxane remains consistent throughout the system. Seasonal properties should consider that the system’s water quality record reflects continuous sampling and is not specific to any single property.
A Worked Example: Reading the Record's Median and Range as a Homeowner Would
The Johnson County system’s eleven tests for 1,4-dioxane showed zero detections above 0.07 µg/L. This means all reported results were below that level, indicating very low or unmeasurable amounts. Since no value exceeded the limit, the median reading is below 0.07 µg/L. Homeowners should understand this as the system’s water being tested rigorously with sensitive methods without identifying measurable contamination.
What the Measured Range Means Against the Relevant Federal Standard, and What It Does Not Mean
No federal maximum contaminant level (MCL) exists for 1,4-dioxane, but the EPA’s cancer risk reference concentration is 0.35 µg/L (0.35 ppb). Since all samples were below 0.07 µg/L, the recorded data fall well below the EPA’s risk guideline. Importantly, detection at or below the reporting level is not a violation or indication of unsafe water. It simply documents the trace presence or nondetect status within the water supply.
Because this is a surface water source serving nearly half a million people through over 150,000 connections, the record reflects an extensive monitoring effort and not isolated conditions in one household's plumbing.
Given these facts, anyone concerned about the presence of 1,4-dioxane in their home water should consider testing their own supply specifically. Such testing, ideally performed by a certified laboratory using sensitive methods, can establish the exact level for that property.
For households investigating treatment options for 1,4-dioxane, equipment like the Fleck 1,4-Dioxane Filter, which ships ready to configure, provides a targeted approach to address solvent stabilizer concerns. This solution is designed to reduce 1,4-dioxane concentrations effectively if present above desired levels.
In summary, the government data confirms no measurable 1,4-dioxane above the reporting level in Johnson County’s public water system record. Testing your water is the key step to know your home's condition, followed by selecting appropriate treatment such as the Fleck product if needed.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2014-05-21. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Water District #1 of Johnson County (KS2009110), KS: 11 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level