Understanding the Royal Treatment at Brightwater

King County’s shiny new sewage treatment plant aims to change our thinking about water usage.
FROM THE PRINT EDITION |
 
 

When a visitor tells Ron Kohler that it smells good where he works, he nods graciously. “I hope you pay particular attention to that smell,” he says. “I’m very proud of it.” The aroma—generic fresh air—is nothing special, except that Ron is a manager at King County’s Brightwater wastewater treatment plant. From its innocuous odor to its high-tech treatment methods, to its impeccably landscaped grounds and bleeding-edge architecture, this gleaming $1.8 billion palace of a public facility near Woodinville, which opened last September after nearly a decade of planning, battling and building, is an enormous leap forward in how we handle our sewer waste—and how we look doing it.

Like most cities, Seattle long left its water untreated. Until the early 1960s, a sewage outfall pipe at West Point (Discovery Park) poured some 40 million gallons of city sewage into Puget Sound each day, staining the water brown and sliming the beach during some tides. Other pipes spilled untreated water into a blighted Lake Washington. Ditto for the Duwamish. Even now, King County’s treatment plants at West Point and Renton, which handle water for more than a million residents, occasionally fail—at West Point, foul air sometimes blows over the adjacent Discovery Park beach, and untreated sewage is spilled into Puget Sound when heavy rains overburden the plant.


The Brightwater facility treats an average of 36 million gallons of wastewater each day; the majority of the acreage is public access, including a 40-acre salmon spawning stream restoration

The Brightwater facility has overcome such issues with new technologies and higher standards. “An older generation had an older understanding of what the public would accept,” explains Kohler. Previous generations just accepted that sewage treatment is a smelly business.

But to the minds of many King County taxpayers, this plant is even more remarkable for its price tag. At more than $1.8 billion, Brightwater has been the most expensive wastewater endeavor in King County’s—and, likely, the nation’s—history. And it’s not even our largest wastewater treatment plant; Renton and Magnolia both have higher capacities. So far, Brightwater is serving 105,000 homes and businesses in north King County and Snohomish County, and will expand to more than 189,000 over time.

Looking over Kohler’s enthusiastic shoulder during a tour of Brightwater (“This is my baby,” he says), it’s easy to see why Seattle Times writer Danny Westneat dubbed this 114-acre suburban spot “The Taj Mahal of Sewage” in an opinion column. Once home to a vast auto-wrecking yard, now the first thing most visitors see—including the hundreds of schoolkids who step down from school buses each week for free tours and wastewater science lessons in the Water Resource Learning Lab—is sparkling hand-blown glass art inspired by the “good bugs” (microbacteria) that scrub dirty water at the plant.

The work (shown above), by artist Ellen Sollod, is part of $4.4 million spent on permanent art at Brightwater, to comply with King County’s “1% for Art” program (sort of—it’s less than one percent, if you’re doing the math). Also on display: works by Seattle sculptors Cris Bruch and Buster Simpson.

Nearby is the Environmental Education and Community Center, designed by local über-green architecture firm Mithun (which also designed the new Seattle Aquarium, REI’s flagship store in South Lake Union and the Smith Tower renovation) for millions more. Certified LEED Platinum, the education center uses 75 percent less energy than comparable buildings. Seventy-two acres of open space contain woods, a salmon-bearing creek and wetlands that naturally filter storm runoff. Planted earth berms will eventually hide the entire facility from drivers on nearby State Route 9, and the lights here go dark at night, to preserve starry sky views. People push strollers, walk dogs and jog along the new pathways at what might also be viewed as the county’s best-funded park. All of these perks are mitigation against lawsuits from those who didn’t want a wastewater treatment plant and pipeline in their backyard: King County has mitigation agreements with 10 entities, including the Suquamish and Muckleshoot tribes, and the cities of Woodinville, Kenmore and Shoreline.


Permanent art installations dot the campus, including Jann Rosen-Queralt’s “Confluence” (above) and Ellen Sollod’s hand-blown glass bacteria (previous photo)

But Kohler, who previously worked at the West Point facility, explains that we can’t even see the biggest expense. “The piping costs more than the treatment,” he says. King County was unable to negotiate a suitable location closer to Puget Sound, so unlike the county’s other plants, this one is several rolling hills away from saltwater—requiring a 13-and-a-half-mile, 13-foot-diameter tunnel to transport treated water to Point Wells, north of Shoreline in Snohomish County, built at a cost of more than $700 million. At Point Wells, two outfall pipes were sunk 600 or more feet into Puget Sound, extending a mile out into the water.

All of the noise over seemingly extravagant spending is understandable. But it’s also drawing attention to how much water we use, and how hard it is to clean that water once we’ve sullied it.

All of the noise over seemingly extravagant spending is understandable. But it’s also drawing attention to how much water we use, and how hard it is to clean that water once we’ve sullied it. To really get the picture, it helps to tour the plant itself (though perhaps not for the squeamish).

Start at the headworks, and you’ll see everything you’ve ever been told not to flush, and more, plastered to perforated, rotating metal screens that trap larger pieces of debris while allowing the rest of the waste to flow through. Odd finds include the women’s driver’s licenses that drop in here on Saturday and Sunday mornings. (“The ladies put them in the back pockets of their Levis in the bars, taverns and lounges,” says Kohler. Sometimes—apparently more often than you’d think—the licenses fall out of their pockets and into toilets.)

A few years ago at the Renton plant, a cat-urine-like smell that is unique to methamphetamine labs triggered a federal investigation. Long before that, tens of thousands of dollars were trapped at the West Point treatment plant after a bank robber, cornered by cops in an Aurora motel, tried to flush away the evidence.


A sculpture by Jane Tsong (words by local poet Judith Roche) blesses the treated water as it exits the facility

Most of what we flush is more predictable. Much of the debris on these screens is condoms and tampons. Tampons may be made of biodegradable materials, but they arrive surprisingly intact after the average four to six hours it takes for what is flushed to get to a Seattle-area plant. So do diapers, disposable wipes, paper towels and Q-Tips, but people flush them anyway—an expensive trip, given that clean water is often used to deliver the refuse, which is then scooped up and driven to a landfill.

The glass-walled thickening area is refreshed with outside air 12 times an hour, but it still smells like a dozen outhouses. Here, the solid components are further treated using a polymer. The long-chain molecule repels the water, which falls away for more processing, leaving behind 95 percent of the solids, which congeal into rolling mounds of brown. This is the heart of what treatment does for us. There’s plenty of perfectly good water to be separated from our waste, because we live in the world’s most water-consumptive country. We use 109 gallons of water per person, per day. That’s far more than in the United Kingdom (28 gallons a day) or even Japan (71). Yet, for the most part, we don’t live with our own waste. We flush it away with lots of water and don’t give it a second thought.

The thickened solids are digested at 98 degrees by anaerobic bacteria for approximately one month. (Methane gas recovered from the digestion process heats the treatment plant and education buildings.) Then, this soil amendment is trucked to farms in eastern Washington to fertilize hops and wheat.

But the water continues on its way. In the secondary treatment building, huge white pipes twist across ceilings. More pipes rise from the floor and curl like fiddlehead ferns. “I call this industrial art,” says Kohler, tipping his head toward the vast works. When he spots a dripping pipe joint, Kohler pulls a slim flashlight out of his pocket to investigate. He types something into his smartphone before moving on.

Treating water in enclosed buildings is one way the plant caps odors, but much of the odor control is done through biochemistry, as smelly hydrogen sulfide is taken from the wastewater as fast as possible. First, bacteria do what they do best—consume the hydrogen sulfide as a food source. The bacteria grow in the wastewater soup, eating up odors. Then chemical scrubbers take a turn. A third step involves activated carbon. But the process most touted at Brightwater is the membrane bioreactor. In this technology, first designed to purify drinking water, wastewater is sucked through porous, spaghetti-sized strands of synthetic material. As the water is pulled through the pores, it leaves behind microscopic contaminants as small as 6 microns, including viruses and some bacteria that aren’t removed in other treatment methods. The membranes can’t filter out some modern pharmaceuticals and chemicals, but even these are reduced in treatment.

In a final step, strong bleach disinfects the water, killing remaining pathogens before the water is released. Some of the water is even reused for flushing Brightwater toilets and watering the landscape, and eventually will be available for reuse outside the facility.


Brightwater welcomes field trips, and public and private events

At the end of the journey: a priceless commodity—clean water—and a few questions: Would cutting down on what we flush save money on sewage treatment? How about using less water generally? These questions lead back to that slick, expensive education center, where schoolchildren touring the facility learn the science behind water treatment, and see where what they’re flushing finally ends up. “We like to teach the kids—and adults—that the same science is happening here as it is in a natural wetland,” says Brightwater education specialist Lansia Jipson. “Nothing ever really goes away; it just changes form.”

It’s part of the larger mission of the center to let people see wastewater treatment first hand and finally grasp the cycle of our water use. “It’s an epidemic in the U.S.—we don’t know where our water, food, clothes or electricity comes from,” says Susan Tallarico, Brightwater Center director. “People are disconnected.”


Brightwater offers a community space, a science lab and an exhibit hall

But perhaps that’s the condition of an older generation. At the education center, kids seem to be learning the lesson. Invited to hang up their “pledges for the planet” beside a sign that reads, one percent of the earth’s water is fresh and available, the kids have some pretty good ideas:

“I pledge to use less toilet paper,” says one. “I pledge to never, ever, put grease down the drain,” says another. A third promises, “I won’t take water for granted.”


Brightwater’s education and community center is open to the public Mon.–Thur., 10 a.m.–4 p.m. Free tours of the treatment facilities are available June 9, July 7 and August 4 (tours run 10 a.m.–2 p.m.; reservations required). Community group tours are available on Tuesdays at 3 p.m. Visit kingcounty.gov/environment/brightwater-center for reservations.

Are High-Rise Wood Buildings in Seattle's Future?

Are High-Rise Wood Buildings in Seattle's Future?

Is Seattle ready for high-rises built of wood after 80 years of concrete-and-steel buildings?
| FROM THE PRINT EDITION |
 
 

When architect Joe Mayo walks into his office, he’s steeped in Seattle history. Mahlum Architects is located in Pioneer Square’s 1910 Polson Building, which served as a warehouse for gold mining equipment during the Klondike Gold Rush. Over the past 100 years, the building has also housed offices and artists’ lofts, and survived two arson fires. So it’s remarkable to see the original old-growth Douglas fir columns still rising from the floor and spanning the ceilings. “It creates a pretty amazing environment,” says Mayo.

Large buildings framed with wood from big trees were commonplace in Seattle and in other parts of the country in the early 1900s. But changing building codes and diminishing availability of large timber put an end to this style. Today, wood buildings are usually one- or two-story houses, while our apartments, hotels and office buildings are nearly all built from concrete and steel. The six-story Bullitt Center on Capitol Hill, which opened in 2013, is the first mid-rise building in Seattle constructed of wood in the past 80 years.

With the advent of a new wood building material called cross-laminated timber (CLT), it might one day become one of many such structures. Proponents say the benefits of building with CLT could be significant. CLT can be used to create buildings that are as tall as 30 stories (and beyond, some architects say) that are better for the environment and aesthetically pleasing, and can be quickly built, help create jobs in economically depressed regional timber towns and are as long-lasting as other buildings. Some research even suggests that wooden buildings offer health benefits for occupants.

Mayo says the material makes sense for our region. “Architecture should feel like it’s a part of a place,” he says. “We’re in the great Northwest, with some of the tallest trees in the world and the best timber in the country, and we have a long history of building with wood.”

But while building codes in Europe and in some other countries have changed to embrace the new material, and CLT buildings as tall as 10 stories are in use in Australia and London, U.S. building codes lag behind. Seattle recently became the first city to allow the use of CLT in construction, but that use is currently limited to five stories for residential buildings and six stories for office buildings.

“The City is open to proposals on larger buildings, but we do have to verify that fire safety and seismic issues have been addressed in the designs,” says Bryan Stevens, spokesperson for the City of Seattle’s Department of Construction and Inspections. That’s because, while these issues have been resolved for buildings in other parts of the world, the U.S. requires domestic testing if building codes are to change.

Washington State University is one participant in a multi-institutional program with the National Science Foundation and the Network of Earthquake Engineering Simulation that is testing how mass timber systems like CLT fare in earthquakes. Hans-Erik Blomgren, a structural engineer in the Seattle offices of the international engineering firm Arup who is a participant in the research program, believes engineers can solve this puzzle. “There’s no technical reason we shouldn’t be designing a building with this material,” he says.

U.S. fire codes have also long prevented the use of combustible materials such as wood in mid- and high-rise buildings, but engineers say code changes to allow for the use of CLT are also achievable. To understand how resistant to fire large pieces of wood can be, proponents suggest thinking of how hard it is to start a bonfire with really big pieces of wood. Not only are such pieces hard to light, but they burn slowly.

In theory, developers could propose larger CLT buildings before codes are changed, but they would have to invest time, money and coordination to get this new building type through Seattle’s Department of Construction and Inspections, with no guarantee that their designs would be approved. “It takes a very special project and specific client and certainly a very ambitious design team to take it on,” says Mayo.

Unless that client steps forward, builders will be waiting for the International Code Council (ICC) to work through the fire and earthquake issues and develop the necessary code changes before mid-rise and higher CLT buildings spring up in the city. 

“We know there’s been a lot of interest in this construction type,” says Stevens, “so we’re trying to be responsive to the demand without giving up safety.”

As with so many innovations, another problem for developers is that material costs for CLT can be high because there are so few North American CLT manufacturers. Developers wait for the price to go down, but manufacturers need more demand for a product. To alleviate this problem, some businesses and legislators are working to help bring CLT mills to Washington state. An Oregon lumber company, D.R. Johnson Lumber, in Riddle, Oregon, recently became the first certified manufacturer of CLT for construction material in the U.S.

Clt was developed in the 1990s by researchers in Austria and Germany who were looking for a use for pieces of surplus wood. The material is created by layering smaller pieces of wood together into a kind of sandwich that offers the strength and insulation found in the massive timbers of the past, and that can be used for the walls, floors, roof beams and posts that make up a building. 

One of the most touted aspects of this material is its role in fighting carbon emissions. Trees absorb carbon and use energy from the sun to grow, which makes them a lower carbon choice than concrete or steel, which not only don’t absorb carbon, but require much more carbon-emitting energy to manufacture. Trees are also a renewable resource, as long as they are harvested from a sustainably managed forest. And CLT can be made from otherwise underused or damaged woods, such as the vast forests of domestic pine that have been killed by mountain pine beetles.

Another selling point, particularly in urban areas, is that CLT panels are prefabricated—bring them to the building site, and your building goes up quickly, with less noise, pollution and traffic delays than with other materials. The eight CLT stories of London’s nine-story Murray Grove apartment building went up in nine weeks.

But building with CLT is not all about practical considerations, says Susan Jones, who owns the Seattle architecture firm Atelierjones and designed her family’s home as the first (and so far only) CLT home in Seattle’s Madison Valley in 2015. The material itself—in the case of her house, CLT primarily from white pine and left unpainted—is a sensual pleasure, from the quality and patina of the wood to the subtle pine smell in the house.

“It’s been incredibly satisfying to live with it,” Jones says. “That’s what architects are asked to do—we create beautiful spaces for people. What’s better than to immerse yourself into this incredibly rich natural environment of wood?”

Here in Washington, there’s enough raw material to immerse us all in that environment. But only a handful of projects in the state have used the material so far—for example, in Jones’ CLT house, in the walls of the Bellevue First Congregational Church sanctuary designed by Atelierjones and on a building project at Washington State University in Pullman. In Oregon, Joe Mayo recently worked on the design for what is to be the first use of U.S.-made CLT on a two-story building project, using panels manufactured by Oregon’s D.R. Johnson.

There are a few other regional CLT building projects in the design process now. In June, Washington state granted design-build contracts to several architects, including Susan Jones of Atelierjones and Joe Mayo of Mahlum, for 900-square-foot classrooms at several elementary schools in western Washington, to be constructed by the end of 2017. 

Another building, Framework, a 12-story building with retail, offices, and housing in Portland, Oregon, is currently in the design process, after a team, which includes Blomgren as its fire and earthquake CLT engineering specialist, won a U.S. Department of Agriculture (USDA) tall wood building competition created to encourage innovation with the material. Winners for 2015, including the Portland team and a team in New York City, each received $1.5 million for the research and development phase of creating buildings using CLT and other engineered wood materials.

At the University of Washington, associate professor of architecture Kate Simonen is leading another USDA-funded study to determine the relative environmental impact of using mass timber in commercial office buildings in Seattle, which follows on other studies indicating that this kind of building will have a lower carbon footprint than other building materials. 

While she’s cautious about reaching premature conclusions in her study, Simonen thinks it might not be a bad idea to start working now to get the structures built in our region. 

“We don’t have all the answers now, but in order to get those answers we need to help lead innovation,” she says. “It makes sense to take some risks in our region to advance a building material that supports our region.”