Pesticide Discovered in Water Supply

The Incident:

A northern New Jersey municipality faced a water contamination crisis when pesticides used for termite control were found in the water supply, affecting 63 homes and leaving them without access to safe water.

What Happened:

The contamination occurred when a construction crew accidentally broke a water main while widening a bridge. During the two-hour repair period, pest-control chemicals back-siphoned from a nearby pesticide company into the water main. Several hours later, a resident contacted the Water Department, reporting that the water appeared milky and had a foul odor.

The Cross Connection:

An unprotected cross-connection allowed pest-control chemicals, including Dursban, chlordane, heptachlor, and lindane, to enter the water main during the main break. The absence of proper backflow prevention measures enabled the back-siphoning of these harmful substances into the public water supply.

Consequences and Actions Taken:

In response, officials immediately shut off the water supply to the 63 affected homes and issued a warning not to drink, cook with, bathe in, or wash clothes with the contaminated water. While the pesticides are not harmful in small doses, moderate ingestion can cause vomiting, and large doses can lead to severe respiratory issues, posing a serious health risk.

To mitigate the situation, officials provided a tank truck with potable water for affected residents and arranged for shower facilities at local public schools. The water pipes were then flushed and super-chlorinated to remove any lingering contaminants.

Prevention Lesson:

This incident highlights the critical importance of maintaining proper cross-connection control and backflow prevention measures. Regular inspections and compliance with safety standards can prevent similar incidents, ensuring the safety of public water supplies and protecting communities from hazardous chemical exposure.

This story, originally written by Watts in "Backflow Case Histories and Solutions," has been summarized to highlight the key points and outcomes.