Thicker Monorail Columns Urged : Transportation: The Ventura Freeway median has room enough for four- to six-foot-wide supports for the proposed line, a report says.

Columns supporting a proposed monorail line above the Ventura Freeway should be thicker than previously proposed so they will be strong enough to withstand earthquakes and being hit by vehicles, an environmental report has recommended.

The report to be discussed today by a panel of the Los Angeles County Transportation Commission says the freeway median is wide enough to accommodate circular columns at least four feet in diameter and perhaps as wide as six feet. Previous design studies suggested 28-inch columns for the 16-mile line from Universal City to Warner Center, one of two mass transit alternatives for the area under consideration by the commission.

A 28-inch steel column “is not recommended for further consideration,” the report said. “Such a column was not found to offer a sufficient factor for safety when exposed to a combination of worst-case structural forces. . . .”

Questions about the columns’ strength and the danger of failure during a major catastrophe were among six major concerns addressed in the environmental study that will be discussed today by the Planning and Mobility Improvement Committee. The panel is expected to direct the commission’s staff to release it to the public for a 30-day public comment period.

In August, after the comment period, the Transportation Commission is expected to certify that the environmental review of the proposed project has addressed all of the project’s environmental impacts.

The other concerns addressed in the study include how the project would affect freeway traffic during the construction phase, the impact on adjacent parks and historical structures, effects on traffic on Canoga Avenue, how it would encourage transit-related development along the route, and whether a parking structure should be built in the Sepulveda Basin flood plain.

The monorail line, which could carry 50,000 passengers per day, is one of two mass transit alternatives being considered by the Transportation Commission for the Valley. An environmental report has already been approved for the rival project--a 14-mile rail line that would follow Southern Pacific’s little-used right-of-way from North Hollywood to Warner Center. Called the Burbank-Chandler line because it would run parallel to Burbank and Chandler boulevards, it would be built as a subway in most residential neighborhoods and above ground in commercial areas.

Proponents of the monorail alternative say it would be cheaper than the Burbank-Chandler line. County transportation officials estimate that the Burbank-Chandler line would cost about $3 billion, but that an elevated monorail line in the Ventura Freeway median would cost $2.4 billion.

The commission is expected to decide between the two projects before the end of the year.

A previous public comment period on the monorail project generated about 600 letters and telephone calls, more than twice the number of comments generated by the Burbank-Chandler line.

“I think this is a reflection that the Valley is taking this seriously,” said David Mieger, project manager for the monorail line. Most of the comments expressed concerns or objections, he said.

Concern over the safety of the monorail columns had been expressed by several groups, including state agencies, homeowner groups, local politicians opposed to the project and the Valley Industry & Commerce Assn.

Roger Stanard, transportation chairman for the association, said his group had raised questions about the column size due to concern about how the line would withstand an earthquake or being struck by a large truck. But he said thicker columns would require additional construction on the medians and would raise the overall cost of the project.

“The more we study, the more we learn that the advantages are not really there,” he said.

Mieger acknowledged that the cost advantage for the monorail alternative is diminishing. He said the estimated cost of the monorail line will increase slightly to take into account the modifications called for in the environmental study.

But he said the monorail line still will be slightly cheaper to build than the Burbank-Chandler line. Mieger said final cost estimates for the monorail line will be released today at the committee hearing.

Gerald A. Silver, chairman of the Coalition of Freeway Residents, which represents five homeowner groups along the proposed route, said he is most concerned about a plan to build a 650-space park-and-ride structure for monorail passengers within the Sepulveda Basin.

The basin--which is meant to fill with water backed up by Sepulveda Dam during heavy rains--was flooded by storms in February, trapping dozens of motorists who had to be rescued by helicopter from fast-rising waters.

“They have no business planning a parking structure in the basin,” Silver said.

The environmental study said the structure would be safe from flooding because the maximum possible flood level in the basin is 714 feet above sea level and the structure’s lowest level will be at least 715 feet above sea level.

Proposed Ventura Freeway Monorail Length: 16 miles Route: From Universal City to Warner Center Column Width: 4 feet or 6 feet in diameter, up from previously recommended 2 feet, 4 inches.