Fleck Lead in Water Filter

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What a Certified Laboratory Test for Lead Reports and How to Read It

Laboratory tests for lead in drinking water provide numerical concentrations usually reported in milligrams per liter (mg/L). These results come from samples taken at the tap or other household points and reflect lead levels in the water at the moment of sampling. A common reporting figure used by public water systems is the 90th percentile concentration, which represents a statistical measure showing that 90% of samples had lead concentrations at or below this level. It does not reflect a maximum or average concentration but rather a high-end value observed in the sampling pool.

For the Dearborn public water system in Wayne County, Michigan, the Environmental Protection Agency (EPA) reports a 90th percentile lead concentration of 0.006 mg/L based on data sampled in 2025. This data reflects lead influences primarily from plumbing materials rather than the water source itself. Understanding this number helps households interpret their own water testing results properly.

How Larger Households Affect Lead Concentrations Compared to Smaller Homes

Household size and water usage patterns influence how lead concentrations manifest at the tap. Larger households or homes with higher water demand may experience more frequent water turnover in pipes, reducing the time water remains in contact with lead-containing materials. This turnover can sometimes decrease lead concentrations. Conversely, if water sits in pipes during low usage periods, lead can dissolve into the water, increasing concentrations.

Seasonal properties or secondary homes often show elevated lead levels due to longer stagnation times. In contrast, residences with consistent daily water use may have different lead profiles. Because Dearborn’s water system serves many households with varying consumption, individual testing is necessary to ascertain specific lead levels inside any home regardless of system-wide data.

Interpreting 'Detected', 'Median', and 'Range' in Dearborn’s Lead Sampling Record

The terms 'detected', 'median', and 'range' in sampling records describe how widespread lead presence is and the variation among measurements:

• Detected: This indicates that lead was measurable in the sample but does not imply a violation or unsafe condition. Detecting lead simply means the test instrument found some level of the metal.
• Median: The middle value of all samples collected, showing the central tendency but not extreme values.
• Range: The spread between the lowest and highest lead levels found across samples. It shows variability but is not a safety threshold.

Dearborn’s 90th percentile figure of 0.006 mg/L shows that most homes sampled had lead levels below this amount, consistent with no health-based violations recorded for the system by EPA.

How Lead Enters Groundwater or Distribution Systems in the Dearborn Region

The Dearborn public water system relies on surface water sources, which typically do not contain lead naturally. Lead found in the distribution or tap water often originates from corrosion of household plumbing and service lines containing lead materials rather than the water source itself. Factors such as water chemistry, pH, temperature, and contact time impact the amount of lead dissolved from pipes.

Municipal treatment processes aim to control corrosivity and reduce lead leaching but cannot eliminate lead exposure from plumbing materials entirely. Therefore, municipal records reflect the system’s compliance with EPA standards but do not replace individual household testing to determine in-home water quality.

The Role of Plumbing Material and Age Separate from the Source Water

Lead in drinking water usually results from plumbing components such as lead pipes, solder, or brass fixtures rather than source water contamination. Homes built before lead plumbing bans or with aging infrastructure are more likely to have higher lead levels at the tap. Even within a community with safe source water, older plumbing can cause elevated lead readings.

Testing tap water after periods of stagnation, such as overnight or after work hours, can reveal lead released from plumbing materials. Understanding plumbing material composition and age is essential for interpreting lead test results and selecting proper treatment methods.

Addressing Lead Water Quality Issues in Demand-Heavy Homes

For households in Dearborn experiencing lead challenges that their current equipment cannot fully manage—especially larger homes or those with high water use—the Fleck Lead in Water Filter system offers a documented solution. This system ships ready to configure and is designed to reduce lead levels effectively, keeping pace with higher water demands without compromising water quality.

While municipal water records show no health-based violations for lead in Dearborn’s system, individual testing remains essential for identifying household-specific conditions. The Fleck technology complements testing by providing a tailored treatment option capable of handling larger volumes of water where lead concerns persist.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2025-12-31. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA SDWIS record for DEARBORN (MI0001730), surface water supply, serving 109976 people: 0 health-based violations of 1 total; lead 90th percentile 0.006 mg/L