Installing a backflow preventer has many advantages. These installations don't take a lot of time, and won't require a significant amount of work. If you are looking for a good reason to install a backflow preventer, here's a few you should consider.
Instead of wasting water by allowing it to flow back into the public water system, a backflow preventer will keep all the water you pull in from the system in your own plumbing setup. Many people who have installed a backflow preventer have experienced savings in their annual water costs.
Safer Drinking Water
Another good reason to consider installing one of these devices is to provide safer drinking water. Instead of runoff water—even from your household pipes—entering the water supply, the water is essentially trapped in your plumbing system. Many people don't think about contaminates from runoff through a water heater, but it can send some pollutants into the drinking supply. If enough homes do this a problem can quickly arise.
Less Wear and Tear
Another reason to consider a backflow preventer is the reduction in wear and tear on your plumbing fixtures. This can include your water heater. As the water heater doesn't have to pull as much water from the system since there is no water loss from backflow, you can extend the life of your water heater by several years.