On a rainy morning in San Francisco, green building professionals and water conservation enthusiasts converged at the PG&E Pacific Energy Center for the 15th Annual Water Conservation Showcase. The expo spanned two floors, featuring 40 vendors exhibiting water conservation technologies and services for residential, commercial and landscaping application. Attendees weighed opportunities in fledgling recycled water regulation, preached the merits of drought-tolerant landscaping options, and explored better ways to evaluate the efficiency of commercial appliances.
The day was broken up by 12 seminars on topics including commercial water conservation, resilient landscaping, and climate-appropriate plants and climate science.
The keynote featured best practices from constructing water conservation systems in the new Salesforce Tower and 181 Fremont high-rise building in San Francisco. The Salesforce Tower team, led by Amanda von Almen of Salesforce’s green building team and Piper Kujak of Urban Fabrick, a sustainability and collaborative design consulting and communications firm, integrated the largest on-site water recycling system in a commercial high-rise building in the United States. This blackwater system collects from the rooftop, cooling towers, showers, sinks, toilets and urinals into a centralized, on-site water treatment station. The water is recirculated in separate pipes to supply many non-potable functions that do not involve direct contact with building occupants. For the 181 Fremont Street project, Jay Paul, a Bay Area real estate developer, hired Urban Fabrick and Aquacell to integrate a graywater system that captures water from rooftops, showers, laundry and bathroom sinks. The wastewater is treated onsite and repurposed for flushing toilets to reduce overall water consumption.
Blackwater and graywater, while both novel water conservation systems in the United States, are different. Blackwater is a typically all of the above system, capturing all wastewater, including wastewater from restrooms. The wastewater is treated and recirculated for non-potable uses. Graywater collects less soiled wastewater from sources like rooftops and sinks. Graywater treats and recirculates water for similar purposes. These systems have potential to affect water conservation in profound ways. Scarcity is becoming a primary issue. In 2010, the U.S. public supply of water used 42 billion gallons per day. In 2014, the Environmental Protection Agency reported that 40 out of 50 state water managers were expecting water shortages over the next decade. According to the Water Research Foundation, most office building consumption is for sanitation, cleaning and irrigation; all of which blackwater systems can accommodate.
The takeaways from the panel included the city’s challenges in accommodating blackwater systems, early engagement and education of the project team, and understanding the impact of implementing a blackwater system:
San Francisco regulation accommodates blackwater and graywater
As part of its negotiations with developer Jay Paul for 181 Fremont, the San Francisco Public Utilities Commission amended the Non-Potable Water Program to mandate the installation of onsite water systems in new developments meeting specified criteria. The regulation instructs new development projects of 250,000 square feet or more of gross floor area to install onsite non-potable water collection and treatment systems. Inspired by early adopters like 181 Fremont, the SFPUC is currently fielding requests for proposals for an onsite water management treatment training program. The SFPUC is also sponsoring Senate Bill 966, which would establish risk-based water quality standards for jurisdictions that create a program for the onsite treatment and reuse of non-potable water.
Education and engagement are key
The conversation between panelists highlighted several strategies to enable a smooth process. First was executive buy-in. Von Almen spoke of the importance in educating executives at Salesforce.com about the principles of blackwater, the budgetary impacts, and alignment with the company’s mission. To ease this process, von Almen teamed with Kujak to provide detailed technical and regulatory resources. Kujak underlined the value of early engagement, including participation in requests for proposals, budgeting, and design charrettes. She explained the value of creating a detailed responsibility matrix, in which all stakeholders were identified. Involving these stakeholders, including Aquacell, from the inception of the blackwater system was essential to identify mechanical, electrical and plumbing challenges and staying within budget.
Impact of blackwater & graywater
The two online blackwater systems in San Francisco are already creating (or reducing) waves. The SFPUC’s headquarters at 525 Golden Gate Avenue uses 65 percent less water, and installing the blackwater system only increased construction costs by 1 percent. According to Salesforce, their system reduces potable water consumption by 76 percent, equal to the yearly consumption of 16,000 San Francisco residents, or 7.8 million gallons annually. Once operational, 181 Fremont’s graywater system is projected to save 1.3 million gallons annually. By integrating this system, the project team was able to capture water use reduction credits and achieve pre-certified LEED Platinum.
The 2018 Showcase expressed the meaningful sea of change in scaling water conservation technologies. These new technologies have manifested in some of the most iconic buildings in the United States, cutting edge water efficiency technologies, and holistic methods of integrating water conservation strategies in the design process. As the wave continues to swell and crest, we continue to look at best practices when it comes to achieving our own clients’ sustainability, LEED and WELL goals.
Click here to view recent projects that used sustainable design and construction strategies.