Tacoma's Titanic: Galloping Gertie's world of wonders
ROB CARSON; The News Tribune
Bob Mester figures he's scuba dived onto the ruins of Galloping Gertie - the first bridge across the Tacoma Narrows, blown apart in 1940 - more than 300 times.
He's been amazed many times on those dives, he says - at the crystalline clarity of the water, at the enormous scale of the collapsed girders, at the diversity of sea life that has blossomed in the bridge's barnacle-encrusted ruins.
But he was never so amazed as he was Wednesday, when he dropped in on one of his favorite places to view pieces of the wreckage, 115 feet below the surface near the Gig Harbor end of the bridge.
Parts of Gertie were buried in rock, he said. Others were draped with heavy anchor chain, sawing back and forth with the tides.
"The place is just devastated," Mester said.
The state Department of Transportation and Tacoma Narrows Constructors, the company building the new bridge, say they're doing only what's necessary to build the new bridge. The rock is needed to protect the old caissons from erosion, they say, and the anchor chains are essential to fix the new caissons in place.
According to Mester and other divers who regularly explore Gertie's wreckage, the construction is violating protections guaranteed to the old bridge because of its placement on the National Register of Historic Places.
"It's outrageous," Mester said. "If somebody tried to do the same thing with the USS Arizona in Pearl Harbor, they wouldn't be allowed to do it. They'd have to figure out some way around it."
Walt Amidon, who owns a Federal Way scuba shop called ScubaSET Adventure Center, echoes Mester's concerns.
Amidon says he has dived in the Narrows two or three times a month since 1961 and is intimately familiar with Gertie's wreckage at the bases of the bridge caissons.
"The first time I made the dive after they started the construction of that bridge, I couldn't believe what I saw down there," he said. "It was like landing on the moon. The marine life we had down there is just gone."
While admitting they aren't sure exactly which parts of the wreckage might have been affected by construction, managers at TNC and the transportation department maintain that no significant piece of the old bridge has been covered or compromised.
Even if significant portions of the old bridge had been affected, they say, it would not have violated historical preservation laws.
"A lot of people think a listing on the National Register (of Historic Places) gives some magic protection," said Rick Singer, the transportation department's business manager for the bridge project.
"The Historic Preservation Act does not require protection at all costs," he said. "You want to avoid where you can avoid. Where you can't avoid, you minimize. What's left, you need to mitigate for."
Allyson Brooks, Washington state's historic preservation officer, agrees.
"A listing on the National Register really doesn't protect anything," she said. "It's just an honor. We are not the preservation police."
The most the state Historic Preservation Office can do, Brooks said, is negotiate for adequate mitigation - that is, accomplishing some other task or project intended to make up for a loss.
The comparison with the USS Arizona is misleading, preservationists say. The ship, where 1,177 sailors and Marines died during the Japanese attack on Pearl Harbor, is protected because it is managed by the National Park Service, not because it's on the National Register.
The only time a "historic" designation offers real protection, said Airyang Julia Park, Pierce County's historical preservation officer, is when local jurisdictions enact specific ordinances.
"The federal law does not have a lot of teeth," she said.
Gertie is not on the county's list of historic places, but it is on the City of Tacoma's list. Tacoma's influence over Gertie stops at the city limit, which lies in the middle of the Narrows channel. The city has no protective regulations for the bridge that go beyond the national standards, according to Jennifer Schrek, Tacoma's historic preservation officer.
In the environmental impact statement prepared for the Narrows project, the state determined the new bridge would have no adverse impact on Gertie's remains. Therefore, no mitigation was required.
Based on his underwater explorations, Mester says that is not the case. The remains have already been compromised, he says, and he thinks something should be done to make up for the loss.
"I certainly am not going to be all upset with the contractors because, if the rock is necessary, it's necessary," Mester said. "You can't build an unsafe bridge. But you can do some mitigation that means something."Salvager watches over Gertie
Mester is not just a weekend sport diver. He's a professional salvager whose Puyallup-based company - Underwater Admiralty Services - specializes in underwater recovery, insurance investigation and marine security.
He has a special interest in Gertie because he was instrumental in getting it placed on the National Register in the first place, more than a decade ago.
Back then, Mester's fear was that the steel in the old bridge would be claimed by salvagers who would haul it up and sell it as scrap. He campaigned relentlessly for the old bridge, extolling its virtues with the passion of a country preacher.
At the time, many people thought Mester was nuts to be worried about the bridge, regarding it as a failure better off forgotten. But he persisted, and federal officials saw things his way.
The ruins of the bridge were added to the Federal Register in 1992.
In part, the nomination read: "The collapse of the Tacoma Narrows Bridge was a hallmark in the history of bridge design and civil engineering. Its impact is still felt in the profession today. The bridge's remains at the bottom of Puget Sound are a permanent record of man's capacity to build structures without fully understanding the implications of the design and the forces of nature."
The old suspension bridge, which had the third-largest center span in the world when it was completed in 1940, shook itself apart in a windstorm after being open to traffic for just four months and six days.
After the fact, investigating engineers determined what was by then obvious: The bridge's roadway was too narrow and light for its length. Also, the roadway had been supported underneath with flat steel girders running along its outer edges. The girders presented a solid front to the wind and made the bridge deck behave like an airplane wing.
On Nov. 7, 1940, when a prevailing wind out of the southwest topped 40 mph, the bridge went into a spastic fit and fell apart. The entire center span, about a half-mile long, fell into the Narrows and sank in about 200 feet of water.
Gertie's replacement, the bridge currently in use, was built in 1950 on top of the old bridge's foundations, which were not damaged in the storm.
The rock Mester saw at the base of those foundations is part of an armoring process that TNC engineers say is necessary to prevent erosion.
Computer modeling and hydraulic tests indicated that, once the new bridge caissons are planted next to the old ones, they'll create vortexes capable of scouring out deep trenches around them.
If nothing were done, the studies indicated, the vortexes would suck rock and gravel off the seabed and whisk it away like a enormous Shop-Vac. Scouring would leave trenches around the caissons at least 75 feet deep, the studies indicated, more than enough to compromise their stability.
The danger of scour is not just theoretical. According to a study at Texas A&M University, scour was responsible for the collapse of 600 bridges in the United States between 1969 and 1999.
The solution TNC engineers came up with in the Narrows entailed building a protective covering of rock too heavy to be washed away in the currents. Since March, cranes equipped with clamshell diggers have been lowering rocks ranging in size from television sets to golf balls - 70 tons in all - in a 50-foot radius around the bases of the caissons.
The new bridge is a "design/build" project, meaning many construction details were not finalized before the project started. Instead, they are refined on the fly.
Placing the rock around the caissons was not an example of that, Singer said. Armoring the caissons was expected from the beginning and was part of the plan back when the original environmental impact statement on the project was prepared in 1999.No serious impact
At that time, the state Historical Preservation Office, which interprets the requirements of the federal law, agreed with the transportation department's assessment that construction of the new bridge was unlikely to have any serious impact on Galloping Gertie.
That conclusion was based in part on sonar scans of the floor of the Narrows, which showed the largest pieces of the old bridge lying where they fell in 1940. Most of them are nowhere near the caissons.
The sonar scans clearly show the big pieces - the old roadbed, the supporting girders and anchor blocks, and 56 concrete boxes the size of houses that were used to hold the old caissons in place as they were being built.
But the diagrams didn't begin to show all of the wreckage, Mester says. And some of what they didn't show, in places most accessible to divers, is now either under newly deposited rock or being whipped to pieces by heavy anchor chains.
Fast currents and deep water make dives to the middle of the channel impossible for all but the most sophisticated and well-equipped divers.
For sport divers who want to see Gertie, Mester says, their only opportunities are the pieces in relatively shallow water near the shore, where the caissons protect them from the currents.
Amidon said he was particularly dismayed about one of those spots near the Gig Harbor caisson, a place divers call the arena, because of how pieces of Gertie's old roadbed were stacked.
"A big, huge anchor chain has just raked across the bottom," Amidon said. "It just tore everything down and rearranged it. Nothing is the same as it was a year ago. That habitat is gone, and I'll never see it again in my lifetime."
Singer acknowledges that some small pieces of the old bridge may have been disturbed.
"Galloping Gertie flew apart in thousands of pieces," he said. "The sonar that was done identifies the major parts. Clearly, it would be impossible to build this bridge and not impact parts of Galloping Gertie. We're trying to protect the major chunks of Galloping Gertie that are down there."Impacts on the existing bridge
Ironically, while state historical preservation officers who reviewed construction plans saw no potential consequences to Gertie, they did predict an adverse impact to its replacement - the bridge currently in use.
At the time, that structure was just 49 years old, a year shy of being eligible to be listed on the National Register. Knowing it would come of age during the five-year construction process, transportation department officials themselves nominated the existing bridge to the National Register. The listing is pending.
The impact of the new bridge on the existing one, historical preservationists said, is a matter of aesthetics.
The bridge's graceful arch, stretching like a strand of green ribbon across the channel, creates a scene that has become iconic in Pacific Northwest culture, they said. Putting a new parallel bridge into that picture, they reasoned, would "modify its character-defining features."
As a way of making up for the intrusion, the transportation department promised to spend $150,000 on a Web site documenting all historical crossings at the Narrows, from prehistoric times to the present. That project, designed to be used in public schools, is to be online in January.
That's nice, Mester says, but it's not enough.
Mester doubts that the transportation department and TNC are being as careful with Gertie as they say they are. He has a problem with the state agency, whose clear mission is efficiency and economy, playing the watchdog to make sure TNC toes the line.
"That's like giving the key to the chicken house to the fox," he said.
Singer, who used to be the head of historical and cultural projects at the transportation department, resents that implication. He has a strong interest in history, he says, and has no intention of letting anything happen to the old bridge.
"That's the fun part of this project," he said.
If it turns out that the divers are right, and a significant part of the old bridge was buried or damaged by anchor chains, Singer says, a portion of the agreement with the state historical office, called an "unanticipated discovery plan," will kick in, perhaps requiring more mitigation.
An example of how that process might play out is already in the works, he said.
While locating anchor lines for the new caisson, TNC discovered that the heavy chain attached to one anchor, designated "F," on the inner ring of anchors on the Gig Harbor side, might come into contact with a 280-foot section of roadway lying on the bottom.
Engineers are not sure whether the chain will touch the wreckage, but TNC has agreed to send divers down when it gets close, to make sure.
Even if the anchor chain does touch the old bridge, engineers don't expect it to compromise the integrity of either the anchor or Gertie.
"It's not going to be slicing this thing in half," Singer said. "It's just going to be rubbing on a portion."
Even so, if it does touch, Singer said, a detailed copy of the anchoring plan will be inserted into the official bridge archives to document what has happened, as a form of mitigation.
Mester is not impressed.
"Again, this does not sound like adequate mitigation," he said.
A better idea, Mester thinks, would be an underwater trail for scuba divers, perhaps linked by cable, that would lead divers to Gertie's most interesting features.
Either that, or an interpretive site on shore, perhaps with monitors linked to underwater pan and tilt cameras so people could see the wreckage and the wildlife for themselves.
"That way," he said. "Everybody could see for themselves what's down there."Rob Carson: email@example.comOn the Net
View Gertie's collapse: www.camerashoptacoma.com/narrows.asp
History: www.nwrain.net/~newtsuit/ recoveries/narrows/gg.htm
Photos: content.lib.washington.edu/ farquharsonweb/index.html