Perchlorate Levels in Harrison County: What Biloxi Residents Should Know

When you turn on your tap in Biloxi, you may wonder about the presence of perchlorate in your water and how it could affect your household. Perchlorate is a chemical that occasionally shows up in water sources due to its use in industrial and agricultural processes, such as in rocket propellants or fertilizers. Awareness of what the local water system detects can help residents make informed decisions.

How Perchlorate Enters Groundwater and the Distribution System in Harrison County

Perchlorate can enter groundwater through soil contamination from industrial sites, agricultural runoff, or improper disposal of materials containing it. In Biloxi, which draws from groundwater sources, perchlorate could originate from historical or active activities in the region. Once in the groundwater, perchlorate can enter the public water supply via wells that tap these sources.

Difference Between Public Water System Records and Private Well Testing

The City of Biloxi’s public water system is monitored regularly by the Environmental Protection Agency (EPA) under the Unregulated Contaminant Monitoring Rule (UCMR). The data reflect broad sampling across the system rather than any individual household. Private wells, by contrast, vary widely depending on location and depth, requiring homeowners to conduct specific tests to determine actual perchlorate levels at their taps. Public system records provide general area insight but cannot substitute for private testing when needed.

Sample Size and Significance in Biloxi’s Data

The EPA recorded 27 perchlorate sample results from Biloxi’s public water system between January and June 2004. None showed perchlorate above the reporting level of 4.0 micrograms per liter (µg/L). This sample size covers the system serving over 23,000 people through more than 9,300 connections, but it is still a limited snapshot in time and scope. A small number of samples means results may not capture infrequent or localized fluctuations.

What the Range of Measurements Means Compared to Federal Standards

Currently, there is no federal Maximum Contaminant Level (MCL) set for perchlorate, which means detections do not represent violations or unsafe conditions according to EPA standards. The reporting level, 4.0 µg/L in this case, is a threshold used to mark measurable presence but not a health-based limit. The absence of perchlorate above this level in the monitoring period indicates the system’s water met the EPA’s criteria for non-detection during those tests.

Influence of Sample Depth, Well Depth, and Water Source Type

Perchlorate concentrations can vary depending on the depth of groundwater samples and the characteristics of each well. Deeper wells may draw water less affected by surface contamination, while shallower sources could show different results. Because Biloxi’s public system uses groundwater, these factors play a role in the quality and composition of delivered water. Detailed local testing or water system reports can sometimes provide insight into such variations.

What Residents Should Not Conclude from This Area Data

The available public system data for Biloxi show no perchlorate detections above levels reported as measurable by EPA during 2004 monitoring. However, this does not guarantee that individual household water is free from perchlorate or that levels never fluctuate. To understand the actual condition of water at home, residents should consider comprehensive water testing targeting perchlorate. For households concerned about perchlorate, treatment options such as the C-Series Perchlorate Filter ship ready to configure and are designed specifically to reduce perchlorate when present.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2004-06-30. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR1 monitoring (2001-2005) for CITY OF BILOXI (MS0240001), MS: 27 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level