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Spring 2016
NCRWA.COM11
feature
N
o one wants to be the one responsible for a town in a race to fix a
water quality problem that spirals out of control. That is why careful
attention is placed on making sure everyone knows the rules and does
their jobs according to plan, especially when it comes to backflow &
cross connection.
Plumbers, lawn irrigation contractors, fire sprinkler contractors,
landscapers, and water purveyors all need to know how to properly
install and maintain a backflow & cross connection device. It’s key
for keeping contaminants out of the water supply. Backflow & cross
connection dates back to the early 70’s when The U.S. Environmental
ProtectionAgency established “The Safe Drinking Water Act.” In North
Carolina, backflow prevention assemblies have been required and cross
connection control programs have been in place in Durham since 1985,
in Apex since 1993, and in Cary since 2003. Still, problems can occur.
How back siphonage can occur:
In 1986, the Fayetteville Times reported a pesticide contaminated
water in a small part of Hope Mills. About 23 households were
affected. The problem is believed to be linked to a waterline break
and a malfunction with a device (Hose Bib Vacuum Breaker) on the
outside water faucet. It was a perfect storm as workers with a pesticide
company started filling one of their truck tanks with water. When
the break occurred, pressure in the waterline was reduced, causing
material from inside the tank to be sucked into the building’s waterline
and out to the town’s water main.
How back pressure can occur:
You may want fries with your burger, but you likely don’t want chemicals
in your soft drink. But that is exactly what customers in a moderate
sized city in North Carolina got after a backflow problem at a fast food
restaurant. It happened in 1974 and more than 300 people were affected.
They were served drinks that had a bitter taste. After some complaints,
syrups were changed but the problem just wouldn’t go away. The local
water department got involved and eventually traced the problem to a
chemical used to treat boiler water in a fertilizer plant. The plant was
located one-half mile away from the restaurant. An investigation at the
fertilizer plant revealed that a check valve on the supply line to the
boiler was leaking and allowed the chemical in the boiler to backflow
into the street water main supplying the restaurant.
A cross connection problem:
In a large southern city, something like you might see in a horror
movie happened at a funeral home. The chief plumbing inspector
received a telephone call that blood was coming from the water
fountains! Plumbing and health inspectors went to the scene and
verified the claims. They found that the blood had been circulating
in the potable (drinking) water system within the funeral home. They
immediately ordered the funeral home cut off from the public water
system at the meter.
Another cross connection problem:
In 2006, results of the Town of Cary’s routine sampling and testing
of its water supply revealed the presence of E. coli. As a precaution,
“Boil Water” notices were issued for all water customers in that
area. Officials believed that the finding was the result of undetected
illegal cross-connection or system work during which bacterial
contamination could have entered the system. Contaminants in the
water system such as E. Coli can cause diarrhea, cramps, nausea,
headaches or other symptoms. To address the problem, crews in Cary
used fire hydrants to flush the system. They also raised the chlorine
levels at the water treatment plant. Meanwhile, people in Cary
struggled to find bottled water in stores which had bare shelves. The
North Carolina Department of Environment and Natural Resources
ordered all restaurants, food stands, school kitchens, lunchrooms,
nursing home kitchens, meat markets, and lodging facilities closed.
There was also threats of lawsuits.
Our new class location
In all of these stories, we see just how important backflow & cross
connection is and why more water systems want to protect their
distribution and certify more backflow testers. NCRWA added a new
True Tales of
Backflow & Cross Connection &
NCRWA’s New Asheboro Location
By Kelly Coggins, NCRWA