After Five Years, Bullitt Center Gets Nod for Rainwater-to-Potable Water System
Seattle's Bullitt Center, considered the world's greenest office building, is sharing lessons learned to get approval for its rainwater-to-potable water system.
Photo by Nic Lehoux
Five and a half years after the opening of Seattle's super-sustainable Bullitt Center, the Washington State Dept. of Health has given the owner the green light to flip the switch on the 52,000-sq-ft office building's treatment system that turns rainwater into potable water.
The Bullitt Foundation, which turned on the system on Nov. 1, is sharing its lessons learned about the protracted permitting process so that others can benefit.
"Achieving approval for the rainwater-to-potable water system has arguably been the most challenging part of the Bullitt Center project," says the Bullitt Foundation in a just-released primer on the subject.
The group attributes the lengthy permitting process, in part, to extreme caution on the part of the regulators, prompted by their charge to ensure the public has safe drinking water.
Safe drinking water is likely the "most important improvement in public health of the last 100 years," says Denis Hayes, the Bullitt Foundation's president. "It’s a responsibility we and the regulators take very seriously."
The group also calls out some missteps during design and construction of the speculative office building, which houses the Bullitt Foundation and several tenants.
"Early in the process, we mistakenly installed some components before we had regulatory approval for the system design," says Hayes. "The mistake got us off on the wrong foot."
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Additional Requirements
Throughout the process, the Bullitt Center team learned about additional regulatory requirements in an iterative fashion. "We would work to comply, then learn about new requirements," adds Hayes. "Given the innovative nature of the project, with components never before used in Washington, this was perhaps to be expected. It was important to get the first project right.
"Finally, when we thought we’d finished the gauntlet, the regulators pointed out that rain hits our solar modules before it flows from the roof to the cistern," explains Hayes. Consequently, the building's rooftop solar panels would be considered an intrinsic part of the water collection system.
"We had to have our SunPower panels tested by the National Sanitation Foundation, just like every other component of the water system," he adds. "That took time."
As a consequence, SunPower panels are NSF-approved for use in tandem with future drinking water systems.
The Bullitt team is offering advice to anyone trying to build a similar system: Understand regulatory requirements, which vary by state, in advance of design. Approached the regulator, often the health department, early in the process.
Before installing any part of the water system, develop a plan with qualified engineers and architects, and have the plan reviewed and approved by the regulator. Then, design and engineer the system to the approved plan.
Consider and incorporate a stormwater mitigation plan. In addition, all new construction should contain a cistern from the start. Adding one later can be more costly.
Chlorine, considered a hazardous chemical, is a statutory requirement for a water system. The Bullitt team explored substitutes but finally gave in because there was no way around the law.
Every building needs a certified water system operator. Bullitt Center outsourced this to a third party to provide a certified operator on a contract basis.
Others have already learned from the Bullitt team. One project that is relying heavily on the Bullitt's experience as a road map for its exotic systems is the 50,200-sq-ft City Services Building in Santa Monica, Calif., currently under construction and expected to open in April 2020.
Based on Bullitt's permitting challenges, the CSB team engaged city, county and state regulators well in advance of completing design of the building systems. Construction of what is likely to be the world's greenest municipal building did not begin until the city had received conditional permits for its composting toilet and rainwater-to-potable water systems.
