What do 'detected,' 'median,' and 'range' mean in the municipal water sampling record?
When reviewing water quality records, it's common to encounter terms like 'detected,' 'median,' and 'range' for various constituents. In Hartford County's public water system serving East Granby and other towns, there are no monitoring data reported for tannins. This means the water utility does not currently measure tannins as part of their routine sampling. However, in general terms:
- Detected refers to whether an instrument or test found any trace of a compound during sampling, not a statement about safety or concentration level.
- Median
- Range
Since tannins are not monitored here, these values do not appear for them in the official record. Recognizing what each term means aids in properly interpreting water data and avoiding misunderstandings about actual water conditions.
How should a homeowner read the water record’s median and range when assessing tannins?
Without federally reported tannins data for this water system, homeowners interested in tannins need to rely on specific water testing of their own supply to assess its presence. Public water systems like Hartford County’s Northern Regional-Western System pull water from surface supplies, where tannins commonly originate as natural organic substances from decayed vegetation.
Reading the available record shows the system has no health-based violations and treats its water with multiple processes. Despite the absence of tannin-specific monitoring, understanding the median and range of other organic compound data (if available) for a system can help gauge potential variability in related constituents. For tannins, direct water analysis using laboratory methods designed for organics is necessary to identify and quantify tannin levels in a home’s water.
How can seasonal or multi-year variation in water quality appear in the record?
Water quality can vary naturally with seasons and environmental conditions. Hartford County’s water system uses surface water, which can carry fluctuating levels of organic matter including tannins depending on rainfall, runoff, and vegetation cycles. Though tannins are not regularly tested by the system, such variation is typical for this source type.
Multi-year data, when available, helps understand longer-term trends or shifts. The lack of tannin data means homeowners must consider potential seasonal changes independently by conducting water tests at different times if tannin presence is suspected. This approach provides insight into whether aesthetic or color issues related to tannins intensify during certain periods.
How does treated water differ at the tap once the Pentair Yellow, Tea-Colored Tannin Water Filter is configured?
The Pentair Yellow, Tea-Colored Tannin Water Filter is designed specifically to reduce tannins, the naturally occurring organic compounds that can impart tea-like color and affect taste in household water. When configured for use, this equipment works by adsorbing tannins from the water before it reaches household fixtures, improving clarity and reducing discoloration often associated with tannins.
This system ships ready to configure for residential use and provides a technically documented solution for tannins where they are present. It can operate alongside other treatment steps already employed by municipal sources, targeting tannins specifically to improve water appearance and aesthetic quality at the tap.
What distinguishes tannin issues from two problems often confused with it?
Tannins are often confused with iron and manganese staining, or with simply colored water caused by pipe corrosion or sediment. Unlike iron and manganese, tannins do not cause rust-colored deposits or scale. Instead, tannins create a yellow to brown tea-like coloration without metallic taste or staining characteristics.
Since Hartford County’s municipal system shows no health-based violations and uses surface water, discolored water from tannins differs from changes caused by aged plumbing materials or corrosion. Testing for tannins specifically requires laboratory organics analysis, whereas iron or manganese testing uses mineral-specific methods. Choosing treatment depends on distinguishing these causes to select a solution like the Pentair Yellow, Tea-Colored Tannin Water Filter for tannins or other filters for minerals.
In summary, the water system record for Hartford County’s Northern Reg-Western System confirms a safe, surface water source serving over 100,000 people with no health violations. While tannins are not monitored by the utility, their potential presence can be identified by home-specific water tests. The Pentair system offers a specialized, documented treatment to address tannins where detected, improving water aesthetics and household water quality.
For official information on the water system serving East Granby and surrounding towns, consult the EPA’s public water system database for CT0473011.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2026-12-31. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA SDWIS record for CTWC - NORTHERN REG-WESTERN SYSTEM (CT0473011), surface water supply, serving 101313 people: 0 health-based violations of 55 total; lead 90th percentile 0.0019 mg/L