The Wisdom of Wastewater Recycling
Not often enough do cities tell their toilet water how much they love it, how much they need it. According to a recent report from the National Academy of Sciences, 12 billion gallons of municipal wastewater in the U.S. is dumped into an ocean or estuary every day, sent out to sea like so much, well, waste. Once water goes down that little hole in the bottom of the toilet, it's effectively disowned.
This is what makes reclaimed water so romantic. It's increasingly common for cities to reclaim or recycle treated wastewater to water parks or refill groundwater sources. Rather than throwing it away, cities are can tell their toilet water not only to come back, but to stay a while.
And for cities that aren't naturally endowed with water, it's making more and more sense to embrace what water there is – even dirty nasty sewage. While many places have begun to see value in reusing treated wastewater, Burbank, California, has emerged as one of the most visible leaders in recycling water.
"We used to take the stormwater and try and get it to the ocean as fast as possible," says Matt Elsner, principal civil engineer at the city's Department of Water and Power. "But now we're trying not to. We're trying to retain it, put more into the groundwater instead of sending it all downstream."
Burbank currently recycles about 10 percent of its water, a figure that's set to increase to about 15 percent in 2013 with the implementation of the city's recycled water master plan [PDF]. The city reuses its treated wastewater to irrigate local parks and to recharge groundwater sources that serve it and its southern California neighbors.
The city recently held a dedication ceremony for the new "EcoCampus" of its Department of Water and Power. It's a demonstration project that employs a number of sustainable design techniques to reduce energy and resource use, and to make sure that even in the heaviest rain events all stormwater will be able to permeate into the ground without ever leaving the site.
The EcoCampus project came about in 2005 when the city built a new power station and replaced some of the aging substations it had on the site. The new power station runs entirely on recycled water, and doesn't put any discharged water into stormdrains. It was named the "Global Power Plant of the Year" in 2005.
"It's not a unique situation for a company to have antiquated facilities or an antiquated campus," says Joe Flores, the department's public information officer. "Typically when you had a facility like this and you wanted to make it sustainable, literally you would knock it down and you'd build a park."
And though the city has also built a park, replacing its 1940s-era substations with a courtyard that uses the aging infrastructure as a trellis, the 23-acre site still functions as a power plant.
"It has all of its sustainability elements and has maintained its original industrial purpose. So all of the economic vitality that this type of operation brings, all of the jobs, good technical jobs, have stayed in Burbank," says Flores.
The project, designed by AHBE Landscape Architects, has now become a demonstration site, where water- and energy-saving design techniques are essentially put on display. Three blocks of an adjacent street have been retrofitted with permeable pavement and bioswales for the drainage of runoff and its parking areas have underground water cisterns that collect and slowly percolate water back into the ground. The project includes three LEED Platinum rated buildings, and is being called the first "sustainable utility campus in the state."
Water recycling is a key element in that sustainable design. Flores says that projects like these are helping the city to increase the amount of water recycling it is able to achieve. Of the 7 billion gallons of water the city uses every year, he expects more than 1 billion to be recycled annually by 2013. The more Burbank is able to recycle, the less it has to bring in from outside, which helps reduce costs for the city and its taxpayers. And for a city in an arid place like the southwest, taking advantage of the water that's there makes a lot of sense.
"Now we're able to capture this water, clean it, redirect it to our aquifers and it becomes a resource, so we don't have to pump that water from northern California," says Flores. "It starts to alleviate some of that pressure."
Image courtesy Burbank Water and Power