How to Tell if Your Well Water Is Making You Sick

Private well water contamination is one of the most underrecognized sources of chronic household illness. Unlike municipal systems, private wells are not continuously monitored, and contamination events often occur without visible or sensory indicators. Water that appears clear, odorless, and palatable may still harbor pathogenic or opportunistic microorganisms capable of causing both acute and long-term health effects.

Common bacterial contaminants in private wells include total coliforms, Escherichia coli, Enterococcus species, Pseudomonas, and environmental gram-negative bacteria that thrive in soil and groundwater. These organisms may enter a well through surface runoff following rainfall, flooding, snowmelt, or irrigation events. Structural vulnerabilities such as cracked casings, compromised seals, shallow well depth, or improper siting further increase risk. Once introduced, bacteria can persist in groundwater and plumbing systems through biofilm formation.

Health impacts associated with contaminated well water vary widely depending on microbial load, exposure duration, and individual susceptibility. Acute exposure may result in gastrointestinal symptoms such as diarrhea, nausea, vomiting, and abdominal cramping. Chronic or low-level exposure can produce subtler effects including fatigue, headaches, recurrent infections, skin irritation, or immune dysregulation. These symptoms are often misattributed to stress, food sensitivities, or viral illness, delaying identification of the true source.

A critical factor often overlooked is secondary household contamination. Contaminated well water does not remain confined to drinking glasses. It contacts sinks, faucets, showers, appliances, and surfaces during daily use. Over time, bacteria introduced through water can establish biofilms on plumbing interfaces and household surfaces, creating persistent reservoirs even after water treatment interventions such as shock chlorination or filtration.

Because of this, evaluating well water illness requires a holistic approach. Water testing alone provides an incomplete picture. A Home Sanitation Confirmation Test can help determine whether bacteria originating from contaminated well water have spread and persisted on household surfaces, offering valuable insight into ongoing exposure risk and remediation effectiveness.

By Chris M., PhD