Consumers are turning to greywater systems to reduce their potable water consumption as a result of growing interest in water savings and concerns over the long-term effects of droughts or water price increase. Over the past few years we’ve seen great efficiencies in flush and flow fixtures, as well as bathroom systems; however, to keep cutting demand, forward thinking projects are moving towards greywater reuse. One system on the market is by a company called Water Legacy.
Water Legacy’s greywater system serves as a greywater filter and storage tank prior to using the greywater to flush toilets within the home. As a residential system, it collects greywater from the showers, baths, and hand sinks and stores it for use in a 55 gallon tank for toilet flushing. Depending on the application, a small pump may be necessary, if you cannot rely on gravity to collect the greywater.
Upon reaching the Water Legacy system, water is treated in a series of steps with a water filter, hydrogen peroxide disinfectant, and a UV light disinfectant system, before reaching the holding tank for distribution to toilets as needed. This disinfectant process is enough to neutralize pollutants, living organisms, and E-Coli, an indicator species for other pathogens.
Prior to delivery to toilets, the water is treated again under the UV light. Additional piping requirements are reduced if you can locate the system near the water supply and sewer outflow. The Water Legacy unit includes an overflow to the sewer system in the event of too much greywater production and a potable make-up connection if there is not enough greywater to supply the toilets. The packaged unit itself comes with a price tag of $3,200.
When greywater systems were first introduced, they were primarily only for landscape irrigation exterior the house. However, many municipalities are allowing greywater indoors for toilet flushing, realizing the potential savings on their water infrastructure.
While some municipal regulations have their own caveats, if they follow the IPC (International Plumbing Code) a dyed hydrogen peroxide can be used in order to dye the water signaling to those in the home that it’s not drinkable water. Other regulations may involve the holding time/tank size, make-up water, and piping identification, so it’s recommended you check with your municipality for the most recent standard. We have even seen signage requirements informing occupants not to drink the toilet water!
Photo credits: Water Legacy (#1-2); The Spinnaker Group (#3).