Let’s face it, flushing our toilets and urinals with clean potable drinking water is waste. Using potable water for cooling tower demand and irrigation is also waste. Up to 95% of water demand in commercial buildings and about 50% of residential demand can be supplied with recycled water. Water scarcity and quality challenges are a global problem. What technical and team engagement strategies are advancing, both here in California and across the United States?
How do we mitigate the "yuck factor" that many people have about reclaimed water use, when it’s been proven safe and effective elsewhere? These concerns were discussed at GreenerBuilder 2019, USGBC's conference in the Pacific region, hosted in San Francisco, where industry experts from across the state led a panel discussion on tactics to improve onsite water reuse.
One example that was highlighted was 181 Fremont, a LEED Platinum multi-use office building in San Francisco, in which my company, Urban Fabrick, Inc., acted as LEED consultant. For this project, on-site water reuse was the only viable pathway to earning LEED Platinum certification, but the owner was concerned that the building's commercial and residential occupants would be averse to the use of reclaimed water. We recognized that while on-site water reuse strategies have been in operation in Israel, Australia, Japan and other countries, it was a foreign concept in the U.S., and many in the architecture, engineering and construction community didn’t know where to begin.
In response, the William J. Worthen Foundation produced a design professional’s guide for on-site water reuse strategies. The goal was to take the highly technical and distill it into easily digestible chunks of text and infographics so that anyone—architect, engineer or policymaker—can pick up the guide and become better informed about on-site water recycling strategies. The good news is that meaningful education and the continuing advancement of building certifications, as we see now in LEED’s expanded Water Efficiency credit category, have been making an impact.
Kathleen Hetrick, LEED AP BD+C, of BuroHappold, shared insights and the range of technical and regulatory challenges from her work on the Santa Monica City Services Building (SMCSB). This project will incorporate several innovative water savings strategies: It will be the first in California for Rainwater to Potable use, it will have the largest installation of composting toilets in California and it will use reclaimed greywater on edible landscapes. Once complete, the SMCSB will exceed the city’s current sustainability standards and is on track to be the first municipal structure to receive Living Building Challenge certification as a Net Zero Water and Net Zero Energy building. This innovative building is scheduled to open next year.
The City of San Francisco has long been a beacon of progressive water initiatives, and Paula Kehoe, director of water resources at the San Francisco Public Utilities Commission (SFPUC), has been its champion. In July 2015, water recycling strategies became a mandate for any new construction over 250,000 gross square feet. This was a dramatic step forward toward a One Water policy. One Water is the concept that all water is a resource. In addition to recycling water, we can recapture energy and nutrients from our wastewater supply.
However, the most obtainable goal right now is matching up nonpotable supply with nonpotable uses. The SFPUC and the U.S. Water Alliance have partnered to convene the National Blue Ribbon Commission for Onsite Non-potable Water Systems to support these systems for individual buildings or at the district scale. While a broad range of benefits can be achieved by implementing on-site nonpotable water systems, widespread adoption of these systems has so far been stymied, due to systemic institutional and regulatory barriers. The National Blue Ribbon Commission is focused on addressing these barriers by establishing model policy frameworks and guidance for municipalities that support local implementation of on-site water reuse.
It was a pleasure to interact with and share the GreenerBuilder stage with other professionals in the building industry working to adopt new innovations and techniques to conserve our precious water resources. Benjamin Franklin once said, “When the well’s dry, we know the worth of water.” Municipalities, utilities, developers, designers and building rating systems like LEED are all part of the push toward holistic water stewardship strategies.