Tunnels: Seattle's boring past filled with thrills
Tunnels R Us, Seattle ... now more than ever.
WELDING TORCHES flare, and sparks shower deep inside this tunnel, 30 stories under Lake Forest Park.
Up top, few people know about, much less appreciate, the work going on down here. To hear our local pols discuss construction of the Alaskan Way Viaduct Replacement Tunnel, you'd think we'd never done this before. Somehow, what was lost in much of the public discussion getting to "yes" on that project was this: Tunnels R Us, Seattle. And they have been, for more than 100 years.
Now, and for about the next five years, Seattle will be in the middle of an unprecedented tunneling boom, from the behemoth viaduct-replacement project to three tunnels being dug to carry Sound Transit users to Capitol Hill and the University District. More than 250 workers are already on the job — 150 mining two tunnels from the University of Washington to Capitol Hill, 107 more working to bore a tunnel from Capitol Hill to downtown. And many more are coming.
This is good news. For while process is the coin of the realm in Seattle above ground, rate of advance is the gold underground, and it's measured by the hour. The underground trade may be Seattle's last bastion of active verbs: Mine it, fill it, drain it, freeze it, grout it, grind it, split it or just plain blow it up. Whatever's in the way of a tunnel alignment, once the crews get going, it probably won't be for long.
In a world where most work is done with a keyboard and dispersed into electronic ether, their work is refreshingly real, lasting, utilitarian. Workers seem also to share a frontier can-do spirit. Masters of a subterranean universe, not for nothing is their line of work called heavy civil: a good name for a grunge band, or a workforce that stops at pretty much nothing.
Hostile work environment? This is a place so alien there is a vocabulary particular to the array of hazards involved: Slickensided clay, raveling sands, perched water tables, glaciomarine drift, shear zones and voids — gaps the size of a small house where chunks of glacial ice melted eons ago. Then there are the prehistoric buried forests, boulder fields and pockets of methane gas.
While Seattle is the extreme-sport version of the tunneling industry, mostly, it's just our ornery nature, what the experts politely call our geologic context. Shoved here from Canada and dropped by the glaciers some 10,000 years ago, the soils that tunnelers confront here are full of the boulders hard enough to survive the trip. We are talking igneous, metamorphic and granitic brutes facing off rock crushers and boring machines tricked out with disc cutters, rock rippers, carbide-tipped steel teeth, the works.
The inconsistency of Seattle's glacial till is also infamous, with material changing from hardpan to gravelly soil to boulders to shifting sands without warning from foot to foot.
"If you go to the Midwest, the layers might go for miles," says Red Robinson wistfully. Senior vice president of Shannon & Wilson Inc., one of the biggest tunnel geotechnical and environmental consulting firms in Seattle, he is a battle-tested vet whose job is determining, as well as possible, what will be encountered on a tunneling job. Not just soils, either: Seattle's buried past also lurks underground: riprap-armored, buried shorelines; abandoned well casings; snapped steel cable from logging mills; mishmashes of fill in long-forgotten, man-made embankments.
Through it all, Robinson helped lead the work on the Mount Baker Ridge Tunnel, and he savors to this day bringing a novel construction technique to completing the tunnel on time and under budget in 1986.
But then, many of the biggest advances in tunnel construction — from the machines that gnaw through the earth to projects bigger and more complex than ever built before — that's Seattle. Robinson has mapped our history of tunneling, and counts more than 100 tunnels under the city, more than 40 miles' worth in all, built since 1890.
One, the Downtown Transit Tunnel, was the first tunnel for buses ever built to be used by rail, too — and it crosses alignment not once but twice, with the double-track railroad tunnel along the waterfront, twining both under and over it with just 5 and 15 feet of clearance, respectively.
No wonder the tunnel tribe here — the workers, engineers, designers, geotechs and construction managers — is known around the world for its innovation, expertise and sheer bench strength. "Seattle Renews its Large Diameter Legacy," noted one of the leading trade journals last spring of the city's commitment to build the Alaskan Way tunnel, which, at 58 feet in outside diameter, likely will be the largest tunnel of its type in the world.
The Mount Baker Ridge Tunnel we zip through on Interstate 90 to get to the Lake Washington floating bridge is still the largest tunnel in soil (as opposed to hard rock) in the world.
The Great Northern railroad tunnel along the waterfront the bus tunnel twines around? That tunnel, completed in 1904, was excavated by more than 350 men with pickaxes, shovels and wheelbarrows. The highest and widest tunnel in the U.S. of its time, the tunnel, having shrugged off at least four big earthquakes, is still in use.
The tunnel drilled into the rock at Snoqualmie Falls houses the world's first underground hydroelectric project, a pioneering feat completed in 1898. It, too, is still in use.
PROVIDING ALL-WEATHER, reliable, energy-efficient conveyance, tunnels in Seattle today remain an option for everything from buses to sewage.
But why Seattle's tunnel affinity? The answer is as old as our topography.
Rising from tideflats to a series of north-south ridges, Seattle's terrain has been a challenge since the Denny Party beached.
Ever notice those purple glass squares in the sidewalk in Pioneer Square? Those are not art installations but skylights into the now largely abandoned underground of the old downtown Seattle. That underground today is covered with the streets and sidewalks built after the Great Fire leveled 25 blocks of the city in 1889.
A great chance, it turned out, for a do-over. Today's street level is actually at the second-story level of the city's oldest buildings, whose feet reside in the unseen netherworld of the city's abandoned first draft. It was just the first in a series of monumental razing, grading, filling, replumbing and tunneling projects undertaken in our obsession to remake the lay of the land.
Tunnels enable us to get around without the bother of going over or around terrain that even after our regrading bender still rises some 300 feet above Puget Sound. And — as with the viaduct-replacement tunnel — tunnels put the utilitarian stuff out of sight, saving aboveground for pretty things, such as waterfront views. Tunnels also put gravity to work, using hills to move water and sewage in pipelines to provide and preserve clean water, a very old Seattle priority.
Those workers on the Brightwater sewage-plant tunnels? Their predecessors built the first tunnels in Seattle beginning in the 1890s. Spurred by a cholera outbreak in San Francisco caused by sewage-contaminated water, those first tunnels were built to carry sewage — untreated, back then — to Puget Sound.
The workers labored using donkeys, picks and shovels, with candles for lighting; mule- or horse-driven fans provided ventilation. Men worked in street clothes and felt hats, hand-shoveling muck and laying temporary wood supports followed with brick lining.
The death toll to build those first tunnels was terrible — losses of at least one man per mile were simply expected.
Those old but still-functioning tunnels, and water pipes bored through wood timbers, were the beginning of a modern, clean-water infrastructure that remains under construction, in the 13 miles of conveyance system for the Brightwater plant from the suburbs of Woodinville to the Sound.
Transportation has been the city's other big impetus for tunnels. The Great Northern tunnel, owned by the BNSF and used for freight as well as Amtrak and Sound Transit Sounder trains, was built right along the waterfront with, shall we say, aplomb unimaginable today. Engineer John F. Stevens recollects in his memoirs directing railroad boss James J. Hill to "secure, under cover, by purchase or option," the lands through downtown Seattle he figured would be needed for the job, and assuring him, "I would go to Seattle and assist with the matter of getting the ordinance (to build the tunnel) which I did . . . We secured the ordinance without much difficulty."
DESPITE LAYERS of Seattle process accreting for better and for worse ever since, we haven't stopped tunneling or innovating. The Robbins Company in Kent was in 1952 the birthplace of the world's first machine of its type, a rock-tunnel-boring machine that could, with a giant, rotating disc fitted with cutter heads, rip through the earth like a T-Rex.
The cutter head of the machine that will dig the Alaskan Way tunnel will be more than five stories high and custom-made for the job, as most tunnel-boring machines are. A mobile, underground factory, it will cruise through the ground like a computer-guided, hydraulic-jack-powered submarine, mining earth, crushing rock, ejecting grout and other soil conditioners from the cutter head to ease passage of the machine through the soil, then slurrying muck mined from the hole out the back.
When, along the way, things get stuck, go sideways, dive, jam or literally grind to a halt, that just makes it more interesting for guys like Greg Hauser.
A construction manager for Jay Dee/Coluccio JV who was hired by King County when another contractor's tunnel-boring machine jammed up on the Brightwater project, Hauser and his team rescued the job by boring in, finding the machine spot on and cutting it up with a torch.
"Things are going to happen, and when they do, we handle it," says Hauser, a career-long tunnel rat who looks like he should be leading a cattle drive.
From the Supercollider in Texas, to sewage tunnels from Chicago to Washington, D.C., Boston and Seattle, he's worked all over the country, maintaining a focused mission statement: "You find out as much as you can about something, you plan it well and get on with it. They want a tunnel from here to there, and you are going to make it for them."
The tunnel, he notes as he marches down it with the second-shift workers, is a beauty: clean, dry, straight. Too bad, he notes, few will appreciate their work. "They make calendars with pictures of bridges," he says ruefully. ". . . This gets filled with shit, and no one ever sees it."
THOUGH THEY labor sight unseen, the workers' pride down here is real. With four years on the job, laborer Willie Bullard didn't mind confessing that at first he got the creeps working underground. "I always think, 'What's going to happen?' But my boss keeps saying: 'Nothing is going to happen to you.' So it's a scary thing. But it's a good thing.' " Like all tunnel workers, he wears a small brass disc with his number on it when he goes underground, leaving a second disc with his number hung on a board at the entrance to the tunnel when he's on the job, moved to the active, at-work side of the board.
That way, if anything happens, everyone knows who's underground. It's an old practice — as are many of the ways of this very traditional business, where till, hard rock or mud is all called muck and the workplace is Down in The Hole.
For many here, tunnel work is what's fed their families for generations, a proud, unionized trade they learned from fathers, uncles, grandfathers. The money is good: Often paying six figures, the underground trade may be one of the last places in Seattle a hard worker with a high-school education can own a house and support a family before age 40.
"Keeps you out of the rain!" cracks Mick McMackin of his job in the Brightwater tunnel. An electrician here, he likes the work because it's consistent, different and busy. "And you make a tunnel, it's going to be there."
Shift foreman Edgar Valles of Everett said over the roar of fans and torches that it was his uncle who first started taking him underground. "Ever since I was a little kid, I wanted to do this work, it was something different from all the other jobs up top."
Hauser squeezes himself through a port in the cutter head of the tunnel-boring machine, all that's left of the tons of steel, hydraulics and electronics the workers cut up after the machine completed its bore-through from Point Wells.
It's interesting to see, after some 30 years of work underground, how instinctively careful Hauser is down here, checking with a gas meter the oxygen level of the tunnel on the far side of the machine's cutter head, where the lighting and ventilation systems have already been removed, and the tunnel recedes into spooky blackness miles away.
Against the darkening distance, his living breath is white, wispy, vulnerable.
"Dragon's teeth," he says, passing a gloved hand over the worn rippers on the cutter head of the machine his team steered to its exact meeting place, head to head with the other section of tunnel they were tasked with completing.
"It's amazing, what we did here," Hauser says. And it is: boring in, to dock one gigantic tunnel-boring machine against another without an inch of tolerance to miss the target. "We were able to move in here from 31,000 feet and come right to it. Dead nuts right where we wanted.
"That's the way we do things."
Lynda V. Mapes is a Seattle Times staff writer. Mike Siegel is a Times staff photographer.
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