In the face of severe droughts, developers seek to reuse the water they have
San Francisco has been at the forefront of water conservation. A 2012 ordinance established reuse standards and was updated in 2015 to require new buildings over 250,000 square feet to collect, treat and use gray water, a term for wastewater minus waste from bathroom.
Rafael Mandelman, a member of the city’s supervisory board, proposed doubling the amount of water new buildings must collect and reuse, and include buildings 100,000 square feet or more.
An analysis in Austin, Texas predicted that the number of water users in the rapidly growing state capital would quadruple in 100 years. To meet some of that demand, the city is offering incentives for developers to install reuse systems, and plans to eventually make them mandatory.
“It’s a paradigm shift, seeing building owners bring their own water to the table, so to speak,” said Katherine Jashinski, supervising engineer for Austin who specializes in on-site water reuse programs. “Businesses moving here from California are interested in sustainability and want to make sure there will be a safe water supply. “
Cutting-edge examples will include even more resource and energy savings. In San Francisco, a system that Epic Cleantec will install in a 55-story mixed-use development project called 10SVN will not only recycle black water, saving about $ 12 million in the first decade, but also the solids of the waste stream in organic soil. . It will even make it possible to recover and reuse thermal energy from wastewater.
“Wastewater is not really waste,” said Mr. Tartakovsky of Epic Cleantec. “It’s clean water, it’s organic matter, it’s nutrients, it’s energy that we can redistribute, which ultimately results in zero waste.”