Perchlorate in Codington County: Key Questions for Watertown Households Deciding on Treatment

What additional perchlorate-related questions would a commercial or industrial user consider compared to a household?

Commercial and industrial users often face higher water volumes and specific process sensitivities that households typically do not. They may need to assess perchlorate levels in relation to regulatory compliance for manufacturing processes or equipment compatibility and consider treatment capacities that accommodate larger daily water use. Households primarily focus on personal and family safety and taste aspects, rather than complex operational factors.

How do public water system records differ from private well testing in what they establish about perchlorate?

Public water system records, such as those for Watertown Municipal Utilities in Codington County, represent collected data over multiple samples from the overall system serving thousands of connections. For example, EPA's monitoring from 2001 to 2005 found no perchlorate above the 4.0 micrograms per liter reporting level in this public system's groundwater supply. This data describes average or representative conditions but does not determine perchlorate levels in any individual household's water, which can vary. Only a specific test of a private well or household tap can provide precise perchlorate concentration for that location.

What happens if perchlorate in water is left untreated in a household over many years?

Perchlorate can interfere with the thyroid gland's ability to take up iodine, potentially impacting hormone production. However, the presence of perchlorate at levels below regulatory health-based violations, such as those recorded in Watertown’s municipal water system, suggests minimal immediate risk. Over many years, if perchlorate were present at elevated levels in household water, some individuals—especially sensitive populations like pregnant women and infants—might consider reducing exposure. Treatment systems designed for perchlorate help diminish this constituent to support long-term household water quality.

What information should a Watertown household write down before seeking advice about treating perchlorate?

Before considering treatment options, document these key details:

• Water source type (municipal or private well)
• Any recent water quality test results, specifically for perchlorate or related contaminants
• Household water usage rates
• Any known sensitivities or health conditions related to thyroid function among residents
• Current water treatment equipment, if any

This information helps clarify the need and scale for any proposed treatment system.

What do the measured perchlorate concentrations in Watertown’s public water system mean compared to federal standards, and what should not be concluded?

Between 2001 and 2005, seven samples from the Watertown municipal groundwater system showed perchlorate concentrations all below the 4.0 micrograms per liter reporting level. Since there is no federal maximum contaminant level (MCL) specifically for perchlorate, these results do not represent violations or unsafe conditions. Detecting perchlorate does not imply water is unsafe, nor does an absence ensure individual household water is free from perchlorate. The data provide a system-level snapshot, not individual household status.

What single test should a household order to determine if perchlorate treatment is necessary?

The definitive step is to obtain a certified laboratory analysis of perchlorate concentration from a sample taken directly at the household water tap or private well. This test will establish whether perchlorate is present above the detection limits relevant for treatment decisions. If perchlorate is detected at levels warranting reduction, a Fleck Perchlorate Filter system ships ready to configure and can effectively lower perchlorate, helping protect household water quality over time.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2002-11-12. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR1 monitoring (2001-2005) for WATERTOWN MUNICIPAL UTILITIES (SD4600356), SD: 7 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level