L.A. Port Span Still at Quake Risk

Almost 16 years after the Loma Prieta earthquake collapsed an elevated freeway in Oakland, killing 43 people, the state has spent $2.4 billion to strengthen the vast majority of bridges it had identified as most vulnerable to failure.

But 16 of the 2,194 spans have yet to be retrofitted, including the landmark Commodore Schuyler F. Heim Draw Bridge -- a lifeline for port traffic between Terminal Island and Long Beach.

The unreinforced spans stretch across the state, from Highway 255 in Humboldt County to a portion of Highway 18 over the Mojave River in San Bernardino County.

Caltrans officials said most would eventually be retrofitted or replaced. Caltrans officials said the 1946-built Heim Bridge was in such poor condition that they probably would replace it with a new one -- beginning as soon as 2008.

The bridge, which carries about 40,000 big-rig trucks a week on the Terminal Island Freeway, is essential in large part because it could become a main port traffic outlet if a major earthquake damaged two larger nearby bridges -- the Vincent Thomas and Gerald Desmond -- said Louis Rubenstein, senior traffic engineer for the Port of Long Beach.

“It’s in terrible shape,” Rubenstein said, adding that some officials worry that an earthquake would prevent the drawbridge from coming down if it were in the raised position during a temblor.

The bridge rises as a square-ish monolith above the Cerritos Channel, marked by its two imposing green columns with a webbing of crisscrossed metal beams. The roadway’s center section rises to allow ships to pass through -- although officials say not many ships still do that.

“Very few tall cargo ships go under the Cerritos Channel anymore,” Rubenstein said. “It’s mostly barges and pleasure crafts.”

He said something must be done soon about the bridge, which is falling apart. “The Federal Highway Administration has a rating system of bridges from 1 to 100,” he said. “And this bridge got a rating of 27.”

A new bridge -- expected to cost more than $170 million -- probably would look more like an overpass than an old-fashioned bridge. And it wouldn’t be a drawbridge.

So far, 669 of the 670 most at-risk bridges in Los Angeles and Ventura counties have been retrofitted, according to Caltrans spokesman David Anderson; 184 of 186 of the most susceptible spans have been reinforced in Riverside and San Bernardino counties.

Though thousands of school and hospital buildings throughout the state still need seismic upgrades, 99.2% of the most troubling state-owned bridges have been bolstered in the last decade, Anderson said.

“They’re not quake-proof,” he said, “but they’re designed to withstand a significant seismic event.”

Ever since the 1971 Sylmar temblor exposed the danger of collapsing bridges, efforts to strengthen them have inspired controversy and accusations of foot-dragging.

Budget cuts, layoffs, political priorities and even disagreements about whether retrofitting was necessary for most of the structures delayed work.

But after the elevated span of the Nimitz Freeway in Oakland came crashing down in 1989, a shaken Caltrans began reviewing the state’s 12,000 bridges to identify candidates for seismic upgrades.

The retrofitting program accelerated dramatically after the Northridge quake caused portions of three elevated freeways to come down. At the time, about 80% of the state’s most susceptible bridges still had not been retrofitted.

Since 1994, Caltrans has reinforced an average of 200 bridges a year, Anderson said.

“From an engineering perspective, we’ve learned how to strengthen bridges and make them more flexible at the same time,” Anderson said. “We will continue to look at new technology and ways of evolving and improving to make our bridges stronger and safer.”

The 16 spans that Caltrans needs to fix include elevated freeway segments and traditional bridges in nine general locations.

Some of the work is virtually complete, such as the five segments of bridges at the Colton interchange on the San Bernardino Freeway in San Bernardino County.

The bridge at Highway 101 at Hollister Avenue in Santa Barbara is slated for replacement, possibly by 2009.

Caltrans also plans to replace a bridge crossing Ten Mile River in Mendocino County, three spans in Alameda County, and one crossing the Mojave River on Highway 18.

Much of the work on the remaining bridges includes strengthening columns, reinforcing footings and anchoring bridge abutments.

The Heim project is by far the most costly.

Caltrans had originally designed a retrofit project of $46 million to upgrade the bridge.

However, it could have cost tens of millions of dollars more for incidental things, including getting rid of all of the lead paint, Rubenstein said.

Caltrans subsequently decided to replace the bridge.

Rubenstein said the structure is a main thoroughfare for truck drivers heading to nearby rail yards and other container transfer facilities.

One option being considered is replacing the old span and building an elevated highway connecting the bridge to Alameda Street just south of Pacific Coast Highway.

Such a route would provide a north-south alternative to the crowded Long Beach Freeway, Rubenstein said.

Unlike the existing lift bridge, the proposed span would rise only about 47 feet above the Cerritos Channel, Rubenstein said.

“The number 47 came about because that is what is required to accommodate the largest fireboat in the area,” he said.

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Shoring up bridges

Caltrans plans to replace the aging Commodore Schuyler F. Heim Bridge in Long Beach rather than strengthen it.

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Some other bridges that still need work

To be retrofitted:

- Highway 255 crossing Humboldt Bay (Humboldt County)

To be replaced:

- Interstate 80 and 580 interchange (Alameda County)

- Interstate 880 at High St. (Alameda County)

- Interstate 880 at 5th Ave. (Alameda County)

- Highway 1 crossing Ten Mile River (Mendocino County)

- Highway 18 crossing Mojave River (San Bernardino County)

- Highway 101 at Hollister Ave. (Santa Barbara County)

Source: Caltrans