Differences Between Public Water System Records and Private Well Testing
Water quality data collected from public water systems covers overall conditions in a region's water supply but does not specify the exact status of any individual household's tap or well. In District Of Columbia County, for example, the Naval Station Washington - Washington Navy Yard public water system serves about 16,800 people through 90 connections. EPA monitoring results for this system focus on collective water sources such as surface water, not individual household plumbing. To accurately know your home's water quality, a direct test from your tap or well is necessary.
Understanding Terms Like 'Detected', 'Median', and 'Range' in Monitoring Reports
The EPA's Unregulated Contaminant Monitoring Rule (UCMR3) reports use specific terms to describe water sampling results. 'Detected' means the instrument measured some amount of a substance, but it is not an indication of a violation or unsafe condition. 'Median' refers to the middle value of recorded measurements, and 'Range' indicates the span between the lowest and highest results. For 1,4-dioxane, the Naval Station Washington system had four samples with no detections above the reporting level of 0.07 micrograms per liter.
Judging Treatment Capacity Against Household Daily Demand
Your household’s water use depends on factors such as the number of residents and daily consumption patterns. If existing treatment equipment struggles to keep up, understanding the capacity required to address constituents like 1,4-dioxane is important. Treatment solutions designed for residential use are selected based on the volume of water processed per day and the concentration levels to be treated. Verifying the treatment capacity is essential to ensure consistent performance, especially when dealing with persistent substances.
Example: Interpreting Median and Range for a Homeowner
Suppose a homeowner reviews the Naval Station Washington system’s 1,4-dioxane results. Since the reported detection values are all below the reporting level, median and range data do not indicate measurable 1,4-dioxane in finished water samples. However, without testing their own tap water, the homeowner cannot confirm the absence or presence of 1,4-dioxane locally. This example illustrates how regional system data informs but doesn’t replace individual water testing.
How 1,4-Dioxane Enters Groundwater or Distribution Systems in District Of Columbia
1,4-Dioxane is an industrial solvent that can enter surface and groundwater sources through various contamination pathways, including discharge from manufacturing sites and improper disposal of products. In the District Of Columbia area, surface water is the source for the Naval Station Washington water system. Although federal sampling did not find 1,4-dioxane above reporting thresholds, the chemical's persistence in water requires ongoing monitoring and effective treatment methods where needed.
Sample Size and What It Means for Data Interpretation
The monitoring report for 1,4-dioxane includes only four samples taken over several months in this system. A small sample size limits the statistical strength of conclusions about overall water quality. The reported absence of detectable 1,4-dioxane indicates that levels were below the instrument’s reporting limit at sampling times, but concentrations can vary. More frequent or extensive sampling would provide a fuller picture of water quality trends.
What Not to Conclude from Area Data Alone
Area-wide data from public system records do not specify the exact condition of any single household’s water. Detecting or not detecting 1,4-dioxane in regional samples is not a direct measure of your home's water. If your current water treatment equipment cannot keep pace, further testing of your private water supply is necessary to identify actual conditions and treatment needs. For addressing 1,4-dioxane efficiently, the C-Series 1,4-Dioxane Filter is designed to handle such contaminants and ships ready to configure for residential use.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-09-09. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Naval Station Washington - Washington Navy Yard (DC0000003), DC: 4 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level