By Patrick Sisson
New York Times
When San Francisco’s Salesforce Tower reopens fully this year after 16 months of a pandemic-induced shutdown, one of its most unusual features will be in the basement.
A series of poured concrete pipes and holding tanks, arranged on two levels in the parking garage like a hidden microbrewery, will transport the dirty water generated by the structure’s daily operations through a six-stage filtration process and will make it clean, non-potable water to use in toilets and drip irrigation.
Occupying the space of 16 cars, the black water system, so called because it treats all sewage, including that from toilets and showers, will filter approximately 30,000 gallons per working day, or 7.8 millions per year. The system, the most comprehensive of its kind in a high-rise tower in the country, is designed to be visited by people – every step of the way is labeled, said Amanda von Almen, responsible for sustainable built environment at Salesforce.
It is also intended to help the company achieve its goal of halving its water consumption. “San Francisco is our home, and there is a drought here,” said von Almen. “We have to do something about it.”
The effort to recycle water is gaining momentum as a severe drought punishes industries in states like California, Montana, New Mexico and Utah.
The concept is not new, but it is increasingly seen as a promising sustainability initiative, especially as more cities and states adopt measures to limit water consumption. , and as a smart hedge against rising water costs and future shortages.
Park Habitat, an office tower that will include a blackwater recycling system during construction in downtown San Jose, Calif., Is designed for a world where droughts are a daily reality, said Andrew Jacobson, manager of the development of Westbank, the developer.
Water conservation advocates say this technology is where solar and renewable energy was a decade ago: technologically feasible, with pioneering projects starting to curve the cost curve and push the concept towards wider accessibility.
“Ten or 15 years ago, a green building was a ‘nice to have’, whereas today it is governed by regulations and the market,” said Aaron Tartakovsky, co-founder and CEO of Epic Cleantec, a wastewater technology startup in San François. “There is no denying that the drought has accelerated the conversations that many are already having.”
Industrial use of water has long been a concern of companies. Reducing the water bill for manufacturing or for cooling data centers has great value in terms of resilience, durability and reputation. But increasingly, commercial real estate is another way to reduce water consumption, decrease dependence on resources and promote green good faith.
Commercial real estate is “where the balance of the pendulum” is for water conservation, said Paul O’Callaghan, founder of BlueTech Research and co-producer of the 2020 documentary “Brave Blue World: Racing to Solve Our Water Crisis” . About a third of water use in San Francisco, for example, takes place in commercial buildings.
Much of the technology behind water reuse is long established and relatively easy to install and use, but it requires local regulations to catch up.
“A few cities, like San Francisco, Los Angeles, New York and Boston, are creating the regulatory frameworks to extend this technology,” Tartakovsky said. “But now states like Hawaii and Washington are looking to create systems that model what San Francisco has done.”
Salesforce installed the blackwater system primarily to show leadership on the issue, said von Almen, who declined to elaborate on costs or savings figures. But there is a long-term return on investment, especially if the cost of water increases over time.
Increasingly, developers are seeing the value of black water systems, especially on a large scale, to provide water for irrigation and cooling towers. Even the cost of modernizing a building, long considered impractical due to the need to add so many pipes for recycled water, is now more viable, Tartakovsky said.
Mission Rock, a 28-acre, $ 2.5 billion multi-purpose waterfront project led by the San Francisco Giants and developed by Tishman Speyer, will use a blackwater system. Each building on the site, which was inaugurated this year, will become attached to it over time. A new not-for-profit utility, Mission Rock Utilities, will build and operate it along with a central thermal energy system.
Water reuse is not adopted only in western drought-stricken states. On Brooklyn’s waterfront, the redevelopment of the 11-acre, approximately $ 3 billion Domino Sugar Refinery will include a more than $ 10 million blackwater system designed not only to reduce fuel consumption. water, but also to reduce the pressure on storm water systems.
Resilience and sustainability are mandatory design criteria to protect the long-term value of the developer’s assets, which benefit from a clean waterway, said Bonnie Campbell, director of Two Trees Management, the company leading the project. .
And the inhabitants are very aware of the quality of the water. “It’s pretty obvious when there’s a storm and the East River smells of poo,” Campbell said.
The Domino Project’s blackwater system, which can treat 400,000 gallons of wastewater per day, is large enough to remove the five development buildings from the city’s combined sewer system and redirect any excess clean water in the river.
“It’s no secret that the city’s infrastructure is overloaded,” said Campbell. “The new developments are increasing the reliance on this system, which is scary, so decentralized systems like ours are a safeguard against that.”
It is also a good investment. The expected return on investment over 10 to 15 years is facilitated by an incentive program, created by the city’s Environmental Protection Department, which offers 25% reductions on water bills.
For the city, water reuse efforts offer many benefits: they save energy and reduce climate change emissions and the flow of water into the sewer system during heavy storms. rains, said Pinar Balci, deputy commissioner of the department.
“We are rich in water and we have no land to build infrastructure,” she said. “Incite offers private developers privileged access points to take advantage of it. “
Other cities are considering changing their infrastructure requirements to encourage or even enforce greater water reuse in commercial structures.
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 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.”
This article originally appeared in The New York Times.