02 May Desert Rain – Building a Better Wastewater System
Water is one of the most basic needs for life. Yet, water management is far from simple. In our desire to provide safe, clean water, we have developed complicated, energy-intensive systems. These systems are expensive too. Keeping the United States’ current water management system functioning will cost an estimated $330 billion dollars in the next twenty years. Constructing a home to meet the Living Building Challenge requires that we ask: Isn’t there a better way to manage our water systems?
We’ve said it before, and we’ll say it again. The Desert Rain House is the greenest custom home we have ever built. It has pushed us to learn more, to collaborate with stakeholders, and to teach others. A great example of this is the water management system we are currently working on. This design includes a rainwater collection system, constructed wetlands, and a sophisticated sewer plan.
Living with Net-Zero water consumption, the homeowners will need to collect all of the water that falls on their property. All of the rainwater collection will come from the roofs. The Galvalume roofs on site have downspouts which lead to gravel filled, concrete basins. These box-like basins are connected to pipes leading to the cistern. Getting all of the water to flow efficiently to the cistern has required creating a very specific and precise grade. Water from the cistern goes through four levels of mechanical filtration and is then treated with ultraviolet light to provide potable domestic water.
A Three Sewer Plan
Most homes have a singular wastewater system – all water from sinks, baths, dishwashers, laundry, and toilets connect to one pipe, which leads to a municipal sewer system. Though initially Desert Rain will be sending all of the wastewater to the City of Bend’s sewer system, we have installed 3 separate lines. The grey water, dishwasher water, and black water will be separated so that, eventually, the grey water will be reclaimed on site.
This system is pushing the boundaries of how water is collected and used. It has posed broad and difficult questions for building homes in Bend, Oregon. We have always had working partnerships with designers and trades people, and now have expanded that collaboration to city, state, and federal officials. We are working closely with The City of Bend and the EPA to expand what can be done with wastewater in our community. City Building Division Manager, Joe McClay, has been very helpful, allowing us to install the three, separate sewer pipes and to test them for future use.
Each phase of building a custom home to meet the stringent standards of the Living Building Challenge poses new and exciting opportunities. Only time will tell how The Desert Rain House and site design will affect our community’s waste water system. We’re looking forward to the possibilities.