Preventing Hazardous Contaminants
When water flows backward through the water supply system, it is called backsiphonage or backflow. The danger comes when a hose is connected to harmful substance. If the pressure in a water main drops while your hose is submerged in polluted or contaminated water, then the water (and whatever is in it) could be sucked back into your pipes and your drinking water supply. Water pressure drops are not uncommon.
They can happen when firefighters battle a nearby blaze or before a city crew repairs a broken water main. Some harmful substances you should be wary of are the chemicals used to fertilize your grass or the weed killer used on your lawn. The cleanser used in your kitchen sink could be hazardous if swallowed, as could the bacteria in the water from your wading pool or waterbed.
Steps to Protect Drinking Water
Fortunately, keeping your water safe from these contaminants is easy. Take the following positions to protect your drinking water:
Always keep the end of the hose clear of possible contaminants.
Buy and install inexpensive backflow prevention devices for all threaded faucets around your home. They are available at hardware stores and home-improvement stores.
Do not use spray attachments without a backflow prevention device. The chemicals used on your lawn are toxic and can be fatal.
Never submerge hoses in buckets, pools, tubs, or sinks.