Household Chromium-6 Concerns in Polk County: Understanding Hexavalent Chromium Levels

The public water system serving Des Moines, Polk County, IA, known as Des Moines Waterworks, provides water to approximately 246,055 residents through about 94,000 connections. According to the EPA's Unregulated Contaminant Monitoring Rule (UCMR3) data collected from 2013 to 2015, this system's water source is surface water, and chromium-6 has been detected in multiple samples.

If you want to understand what the UCMR3 survey measures and how it relates to your household

The UCMR3 survey was designed to track the presence of certain unregulated contaminants across public water systems nationwide. It offers a snapshot of reported concentrations but is not a compliance test or a definitive assessment of any individual home's water quality. Detection above reporting levels indicates the presence of a substance, but it is not a health-based violation or a direct indication of risk for a specific household. For hexavalent chromium, the reported values for the Des Moines Waterworks system showed detections in 16 out of 24 sample results, with the highest level measured at 2.62 micrograms per liter (µg/L), equivalent to 2.62 parts per billion (ppb).

If you consider how chromium oxidation states may shift from the water source to your tap

Chromium exists in multiple oxidation states, with chromium-6, also known as hexavalent chromium or chromium(VI), being one form. Changes in chemical conditions—such as oxidation or reduction reactions—can convert chromium between its hexavalent and trivalent forms. The conditions in the water source, treatment processes, and the distribution system can influence these transformations, which means the form and concentration detected at the tap might differ somewhat from the raw water sample. Consequently, your home's water chemistry may vary, and testing your own water is necessary to determine actual levels of chromium(VI).

If you wonder how chromium-6 enters water supplies in the Des Moines area

In the Des Moines region, chromium-6 presence in the public water supply originates primarily from the surface water source. Hexavalent chromium can occur naturally or enter water bodies through industrial and environmental processes. The detected levels reflect what was measured in the source and distribution water during the monitoring period; they do not indicate an individual household's water condition. Hexavalent chromium is a recognized form of chromium that can dissolve in water and occasionally is detected during routine monitoring.

If you need to evaluate treatment capacity based on your household water use

When considering treatment options to address chromium(VI) at home, it's important to match the treatment capacity to your daily water consumption. Water treatment technology designed to reduce chromium-6 concentrations must be adequate for your household's flow rate and volume requirements. Equipment that ships ready to configure can be selected and set up to meet typical residential needs. Assessing your water usage helps ensure that any solution you choose effectively treats the water while maintaining convenience and efficiency.

If you want to know what the measured chromium levels mean against federal standards

The EPA's maximum contaminant level (MCL) for total chromium is 100 micrograms per liter (µg/L), applying to all forms combined, including chromium(III) and chromium(VI). The reported highest level of hexavalent chromium in the Des Moines Waterworks system was 2.62 µg/L, which is well below the total chromium MCL. Notably, there is currently no federal MCL specifically for hexavalent chromium. Detection above reporting levels does not indicate a violation or unsafe water under federal standards. These figures provide information on the presence and concentration range but do not constitute a health-based finding on their own.

It is important not to conclude from these area-wide monitoring results that your household water contains the same chromium-6 levels or that it poses a safety concern. Testing your own water is the only way to know the specific chromium concentrations at your tap. The Pentair Chromium-6 Filter offers a documented approach for homes seeking to reduce hexavalent chromium in drinking water, tailored to meet residential daily demand and water quality conditions.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2015-04-01. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR3 monitoring (2013-2015) for Des Moines Waterworks (IA7727031), IA: 48 results across 2 listed contaminants, 32 detections above the reporting level; no federal MCL for hexavalent chromium; total chromium MCL 100 ug/L