City Hall Renovation Offers a Lesson in Civic Archeology

Jim Treadaway started at the bottom in Los Angeles’ storied City Hall, but he’s working his way to the top.

Below street level, he proudly showed visitors the seismic improvements, the base isolators and the massive steel columns with protruding Nelson studs.

Next he came to the terra cotta bricks, the naked exterior of the rotunda, the bare corridor walls no longer covered in marble.

Finally, he was at the top, on the observation deck of the 27th floor of old City Hall, looking out over the city on a sparkling November afternoon.

“You hope for one of these in your career,” said Treadaway, the structural engineer on City Hall’s massive and ongoing renovation project. “And we’ve got a great one.”

When it is completed in April 2001, Los Angeles’ 71-year-old City Hall will be a rebuttal to those who say that the city too readily destroys its history and a testament to Treadaway and the others like him who believe the future can be lived in a renovated past.

City Hall, the idiosyncratically majestic landmark--once Los Angeles’ tallest building--is closed to the public and to the scores of filmmakers who have used it over the years. It’s been the Daily Planet building in the Superman TV series, the setting for a key scene in “Chinatown,” the closing scene in “L.A. Confidential,” “Dragnet’s” police headquarters and is soon to be the backdrop for “A Civil Action,” one of the last features shot there. Los Angeles police officers’ badges even feature an outline of the building.

The City Council and various departments moved out of the historic building in March, making City Hall East the seat of city government.

The $273-million City Hall project, so far a mere five days behind schedule, is an enormous undertaking that primarily involves seismic retrofitting. The building cost the city $9.7 million in 1928.

It is also an exercise in civic archeology, in which the past has definitely met the future. And, it is nothing if not a labor of love for many of those working on it. Consider:

* One of the three architects of the original building was Albert C. Martin, a Los Angeles designer and structural engineer whose material legacy is sprinkled from downtown to the Mid-Wilshire district. His grandson, Christopher C. Martin, also an architect, is heading the design of the building’s modernization.

* Architects, engineers and other construction team members are still drawing plans by hand--as the others before them did in the 1920s--but this time, they are also using the Internet, electronically mailing designs, updates on costs and timelines, and even exchanging digital photographs.

* The marble that lined the walls, primarily on the third floor, and the granite Spring Street steps have all been removed and will be cleaned and replaced in their exact locations--a kind of jigsaw puzzle for construction workers.

* The hollow, terra cotta bricks lined with grout that made up the interior walls of the building (“State of the art in 1928,” Treadaway says, smiling), will be replaced with steel studs and drywall, the 1990s version.

* The communications system in the building--which also served as police headquarters before Parker Center was built--will remain and will probably be updated, allowing city leaders to use it as a command center in a major emergency.

But all of that is far in the future for Treadaway and City Engineer Stan Morimoto, who oversees a dozen project team members as well as varying consultants.

Now, they are concerned with the 250 workers welding, hauling and pounding in what was once the parking garage. It is cavernous and dark, filled with the sights and sounds of construction: sparks flying from welding torches, whirring large fans, Bobcats circling and removing yards and yards of dirt.

All of this is in preparation for installing what could be considered the largest shock absorbers ever made: The building will sit on 532 base isolators, imported from Japan. The isolators, which look like flattened spools of rubber and steel, will enable the building to withstand a magnitude 8.1 earthquake; the isolators flex horizontally up to 21 inches in three directions to absorb movement and reduce shaking inside the historic building.

To wedge those isolators under the columns, however, would have taken Superman himself, if it weren’t for the hydraulic jacks that actually lift the columns while the isolators are placed underneath. Once that is complete, the columns are fastened so they cannot move horizontally in an earthquake.

As far as he knows, Morimoto says, City Hall will be the tallest retrofitted building in the world with base isolators. San Francisco recently used the technique for its new library and City Hall buildings, and Salt Lake City did the same for its historic civic center.

“Everyone comes to the same conclusion with a historic building,” Treadaway said. “Base isolation protects the building.”

Moving up in the grand building, Treadaway and Morimoto pointed to the exposed terra cotta bricks, held together only with grout. Those bricks explain why, after the 1994 Northridge earthquake, the so-called tower portion of City Hall was closed; another earthquake could have led to even more damage on those floors.

Overall, Martin said, the old building held up well over the years, and for that he credits his grandfather, a pioneer in so-called moment frame engineering, in which steel-framed buildings are expected to move and absorb energy in an earthquake.

“He didn’t quite know what he was doing, but he did understand that the building would absorb energy,” said Martin, 48.

The trick for all of the architects, designers, engineers and assorted other construction experts in this project is to maintain the historical aspects of the building.

“It’s a landmark . . . that is known all over the world,” said Charles Merrick, vice president of Bovis Construction Corp., which is working with the city on the project. “There are unique, historical elements . . . we are trying to upgrade and modernize.”

Martin is unequivocal.

“I love it,” he said. “It’s truly a passion. The chance to keep the old building and do this seismic strengthening is really a thrill for us.”

The walls on the third floor, perhaps the area best known to visitors (and moviegoers), are bare now, with masking tape labels marking the spots where heavy marble once lined the corridors. The magnificent rotunda, which has more than 4,000 inlaid pieces of 46 types of marble, and the City Council chamber, with Italian marble columns and a green tiled arch, remain intact. All will probably be restored. That project, however, is separate from the seismic work; it will be funded primarily by Project Restore, another city initiative.

“Money needs to be raised,” Al Avila, who heads Project Restore, said as he entered the red hoist elevator that runs along the Spring Street side of the building. “Now would be the perfect time to do all this work.”

And when it is complete, city officials like Avila hope to reopen the building in lavish style--as their predecessors did in 1928.

“I can just see it,” Avila said in the observation tower, where the walls of one reception room still bear this inscription:

“The City Came Into Being to Preserve Life, It Exists for the Good Life.”