KUSA - Unsuspecting Coloradoans could be drinking water containing bathroom bacteria or lawn chemicals if there's a change in their home's water pressure.
9Wants to Know and I-News at Rocky Mountain PBS teamed up to expose the dangers of unprotected cross connections in plumbing. Those often undetected plumbing problems can make people sick.
WATCH: Tutorial on detecting household cross connections
The Colorado Department of Public Health and Environment keeps tracks of mass illnesses from contaminated water. The most recent incident occurred in October 2012 at a Colorado Springs medical plaza. Twenty-six people went to the emergency room with headaches or upset stomachs.
"The water had a frothy look and kind of a funny smell," said CDPHE Lead Drinking Water Engineer Tyson Ingels. His investigators determined a maintenance worker hooked a hose from a fresh water pipe to the building's heating system. Investigators found the worker forgot to unhook the hose allowing antifreeze and possibly other chemicals to backflow into the building's drinking water supply.
In plumbing, a cross connection happens when a safe drinking water supply comes in contact with water that has unhealthy chemicals, sewage or bacteria. The contaminants or pollutants you shouldn't drink can get sucked backwards into your drinking water pipes if there's a drop in pressure. Drops in pressure can be caused by a water main break, firefighters tapping a hydrant, or even the flush of a toilet, can cause backflow to occur.
There aren't any studies on how often Colorado businesses have cross connections, but the state keeps records on hundreds of community water systems. I-News analyzed those records to determine how many water systems failed to follow all the regulations regarding cross connections and backflow.
"We don't want anyone to get sick from the water," Ingels said.
In homes, the most frequent places for cross connections are at outdoor hose bibs and inside toilet tanks, according to Joseph Montoya, who teaches plumbing code at Red Rocks Community College.
SLIDESHOW: Cross connection dangers in your home
"People will connect hose end sprayers to spray their lawns with chemical then they will leave that connected," Montoya said. "And if you don't disconnect it, it could easily come back into your house."
There are also risks of backflow from a hose submerged in a bucket of cleaning solution or a backyard pool. Montoya says an anti siphon valve attached to the hose bib itself or a vacuum breaker screwed on to the end of the spigot can prevent backflow and protect the water lines.
The grossest place to have a cross connection is inside the toilet tank. To prevent backflow, make sure the top part of the fill valve or a ballcock is at least one inch higher than the overflow tube, located in the center of the tank. Sometimes do-it-yourselfers will install the fill valve lower. They may intend to conserve water, but they risk the possibility of contamination if there is a backup in the toilet.
Water that is contaminated due to backflow can make people sick and they may never realizing the true cause.
"A lot of times it is misdiagnosed as food poisoning," Montoya said. "It made you sick and it's, 'what did you eat?' The doctors never really go to 'what did you drink?'"
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