BACKFLOW AT A PEST CONTROL COMPANY

DATE OF BACKFLOW INCIDENT: June 1987

LOCATION OF BACKFLOW INCIDENT: Fair Lawn and Hawthorne, New Jersey
SOURCES OF INFORMATION:

- Drinking Water & Backflow Prevention, Volume 5 Number 3 (March 1988)
- Pacific Northwest Section of the American Water Works Association, Summary
of Backflow Incidents, Fourth Edition, 1995
- Watts Industries, Inc.; Watts Regulator News/Stop Backflow


CASE HISTORY
On June 24, 1987, a construction crew inadvertently broke a water main while
widening a bridge in New Jersey. Several hours after the water main was
repaired, a customer called the water department to complain that the water
was milky and smelled bad. Pesticides had backflowed into the public water
system.

The backflow incident happened at the time the bridge construction crew
broke the water main. Because of the water main break, a siphoning action
occurred in the water mains. Concurrently, a pest control company employee
was rinsing a tank that contained a weak solution of the pesticides
heptachlor and chlordane. The hose that the employee was using had the
pesticide Dursban on it. One to three gallons of the pesticides were sucked
through the pest control company's potable water system and into the public
water system.

Several people drank, and watered their gardens with, the contaminated
water. Fortunately, however, there were no immediate illnesses or injuries.
After receiving the complaint about milky and bad smelling water, the water
department immediately shut off the water supply to the 63 customers
affected by the water main break and notified them not to drink the water or
use it to cook, bathe, or wash clothes.

The 63 homes and businesses went without usable water service for several
days while affected water mains and plumbing were flushed and disinfected. A
tank truck provided potable water for drinking and cooking. Shower
facilities at the local public high school and middle school were made
available for use by affected residents.

Because the pesticides stuck to piping, the plumbing at nine locations had
to be replaced. At all other locations, analysis of water samples showed
that the pesticides were not detectable.

The pest control company assumed responsibility for the backflow incident
and paid for the necessary replacement of plumbing. Nevertheless, 21
homeowners sued the pest control company for $21,000,000. They claimed that
the pest control company irreparably damaged plumbing fixtures, that
residents continue to suffer physical injury, and that residents have been
subjected to mental distress, inconvenience, and loss of property. In
addition, the homeowners asked the pest control company to pay medical
expenses incurred because of the incident and to >maintain a health
surveillance program for affected residents.

The water department ordered the pest control company to cease operating
until a backflow preventer was installed at the water service connection to
the pest control company. Following installation of a backflow preventer,
the pest control company resumed operation