Pentair Yellow, Tea-Colored Tannin Water Filter

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

When you send a water sample to a certified laboratory to test for tannins, the report will typically provide a concentration expressed in milligrams per liter (mg/L). This number quantifies the amount of tannin compounds dissolved in the water. Since no federal or state limit is established for tannins in public water systems, the report is mainly useful to confirm presence or absence and relative concentration. Because tannins are naturally occurring organic substances that can color water a yellow or tea-like shade, understanding the test result helps clarify if tannins could be causing visible discoloration in your household water.

What the Measured Range Means Against Federal Standards, and What it Does Not Mean

Currently, no government monitoring data exist for tannins at the Woonsocket Water Division public system or in federal datasets. The system’s source water is surface water, which can be susceptible to tannin presence due to organic material runoff, especially from areas with trees or peatlands. There are no EPA health-based violations related to tannins recorded for this system. Importantly, even if tannins are detected, this does not imply a health risk or legal violation. The primary federal standards focus on health-related contaminants, not aesthetic issues like water color caused by tannins.

How Seasonal or Multi-Year Variation Shows in the Record (Dates and Ranges Given)

The Woonsocket Water Division’s EPA record includes a health-based violation unrelated to tannins and samples for lead in plumbing, but it does not include tannin monitoring. However, surface water sources in Providence County typically experience seasonal variations in organic content, with tannin levels potentially increasing during fall leaf drop or wet seasons due to runoff. Without direct tannin data, this is a general observation consistent with surface water behavior rather than a specific trend for the area’s tap water.

A Worked Example: Reading the Record’s Median and Range as a Homeowner Would

Assuming a homeowner suspects tannins due to tea-colored water, their best step is to obtain a certified tannin test of their tap water to confirm. The Woonsocket Water Division reports a lead 90th percentile at 0.002 mg/L for plumbing samples as of late 2025, evidencing compliance with lead rules but unrelated to tannins. Recognizing this distinction helps avoid confusion—tea color may come from tannins in source or distribution water but must be differentiated from plumbing or other contaminants through testing.

Which Fixtures, Appliances or Processes Are Affected First and Why

Tannins typically cause discoloration noticeable first in cold water taps used for drinking or cooking, since they impart a yellow to brown tint without affecting water safety. They can stain laundry and utensils and sometimes cause minor taste changes, but they do not cause scaling or health concerns. Appliances relying on clear water, such as coffee makers and ice machines, may show visible effects sooner. Hot water systems usually have less visible staining since tannins can degrade at higher temperatures.

Maintenance Rhythm of the Documented Technology in Plain Terms

The Pentair Yellow, Tea-Colored Tannin Water Filter ships ready to configure for residential use and is designed to reduce tannin staining and discoloration. To maintain its effectiveness, the filtration media requires periodic regeneration with a salt-based solution following the manufacturer’s schedule, typically tailored to water usage and tannin levels. This routine keeps the filter operating efficiently by flushing accumulated tannins and restoring capacity, ensuring consistently clearer water at taps.

In summary, the Woonsocket Water Division public system supplies surface water that can be prone to tannins, although no direct tannin measurements exist in official records. Checking your own water through certified tannin testing is the reliable way to quantify the issue. The Pentair System offers a documented approach to addressing discoloration from tannins for households experiencing these symptoms. For official data on Woonsocket’s water quality, consult the EPA system record at data.epa.gov.

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 WOONSOCKET WATER DIVISION (RI1559518), surface water supply, serving 45828 people: 1 health-based violations of 23 total; lead 90th percentile 0.002 mg/L