DUAL PLUMBING SYSTEMS: REUSING WATER AND SAVING THE PLANET
There are a couple different ways to reduce water usage by reusing water in your building. The first is called a dual plumbing system, and the second is greywater. We’ll look at each of these in some detail to see which is the best option for your building.
A Step Above Regulations
Most states mandate that buildings utilize low flow toilets to reduce the amount of water used in each flush. This is a good measure, but some folks who really care about the environment felt that they could take it a step further. These people began developing and implementing systems such as dual plumbing and greywater systems to reduce their water usage, and have changed the way water is consumed in many buildings today, and hopefully many more in the future.
Reusing Water with Dual Plumbing Systems
A dual plumbing system is exactly what it sounds like: a plumbing system with two sets of pipes. This system is designed to run potable (drinking, washing) water and reclaimed (flushing, irrigating) water through the building in separate piping systems. The two types of water never touch, but they allow water that isn’t drunk, such as toilet and irrigation water, to be reclaimed water.
This reclaimed water is still filtered, there are no harmful bacteria in it, but you wouldn’t really want to drink the water. But it makes sense, why use drinking water to flush a toilet? You don’t need to, and this system realizes and takes advantage of that.
Reusing Water with a Greywater System
You can also reuse water in a system called greywater, which involves capturing rainwater and using it for the same applications as dual plumbing: toilet flushing, irrigation, etc. The only major difference is that this system captures rainwater, whereas a dual plumbing system pulls water that is filtered by the local water authority.
Both of these system require forethought to be installed correctly. Making plumbing changes for an entire building can be very tricky if the building is already in place. It’s best to consider these for new construction and to implement the systems in buildings moving forward. These systems also require a sizable investment in plumbing costs – material, design, and labor – upfront, so they are generally reserved for those with good-sized budgets and a passion for preserving and improving the environment around them.