September 11, 2018 Alex Spire

AHBE LAB Net Zero Water At An Eco-District Scale

Verdical Group’s Net Zero Conferences attract the brightest minds in the industry to share their sustainability success stories.  This year, we were joined on stage by AHBE’s Gary Lai who gave a comprehensive presentation on net zero water and the benefits of resource management in California.  Before presenting, Lai published a write-up that you can view here, or below:

Water conservation is an ongoing topic of discussion and exploration here at AHBE. From simple water-saving tips to broader statewide drought-related issues, our staff and AHBE Lab contributors have advocated for smart water habits and policies.

Net Zero Water is the next step for water conservation supporters and serves as a concept and framework for water self-sufficiency. Simply put, Net Zero Water practices could help us achieve independence from the water grid and get all the water we use from nature and treated greywater.

In Southern California, achieving Net Zero Water is very difficult unless you have a huge parcel of land with a tiny house. A building-by-building solution is impractical. A household would have to implement the equivalent of a wastewater treatment plant in its garage, which is not economical for most people. Water independence through Net Zero Water strategies is possible for Californians if we think about them in terms of a collective achievement at the neighborhood, city, or county level.

I have become fascinated with the thousands of man-made lakes we built in our state in the 1980’s and 1990’s. Although they are lovely private and public amenities, these lakes were being supplied by millions of gallons of expensive imported water from the Owens Valley and Northern Sierra Nevada. At one point, the make-up water from private man-made lakes ranked number one for water usage in our state. Consider the impact on our water supply if the lakes were taken off the grid and used instead to supply treated drinking water to a whole community or eco-district.

 

 

Graphic by Los Angeles County Dept. of Public Works for Magic Johnson Park Phase 1A project.

 

I am currently working on a project in the South Los Angeles area. The project calls for improvements to an existing park called Earvin “Magic” Johnson Park which serves LA’s Willowbrook community. Among the new and improved park amenities, we are taking the 8-acre south lake off its current domestic water source and replacing it with treated recycled stormwater. We will then use the lake water to irrigate the remaining 120 acres of the park. Consider the following:  how much more effort would it really take for the next step toward Net Zero Water at an eco-district scale? The recycled irrigation water we are generating is almost at drinking water quality now. What if we treat the lake water for drinking quality and use it to supply the neighborhood?

California’s population is projected to grow to 50-60 million by 2050 and, according to the most recent climate models coming out of Lawrence Livermore Labs, the state will have 10-15% less water. We must explore options that will allow us to live, grow, and prosper with these challenges.

If you are interested in learning more about Net Zero Water, please join me at the 2018 Net Zero Conference on September 13. I have more to share on this subject and I look forward to meeting you at the conference!

 

 

Image: prepared by Gary Lai for his presentation at the Net Zero Conference.