Leaks, Tunneling Undermined Street : Transit: Traffic reopens on buckled stretch of Hollywood Boulevard. Subway excavation is at a standstill; responsibility for repairs is unclear.

Water leaks and tunneling into soft earth caused the ground above on Hollywood Boulevard to sink up to nine inches and prompted a halt in excavation for the Los Angeles Metro Rail subway project, officials said Monday.

The famous thoroughfare was reopened to traffic Monday afternoon. But it was unclear how long the subway tunneling would remain at a standstill and who would pay to shore up the tunnels and repair the damage aboveground.

Life on the Walk of Fame was anything but back to normal.

“What is this--from the earthquake?” Leslie David, an actress, said after a police officer turned her away from walking down Hollywood Boulevard.

Store owners also were grumbling over lost business opportunities.

“Everybody’s up in arms,” said George Erickson, owner of “By George!” a sort of Frederick’s of Hollywood for men.

Metropolitan Transportation Authority officials blamed the sinking on two problems: loosely packed, sandy soil and leaky water pipes.

Both problems have caused the earth to sink along a multi-block stretch of Hollywood Boulevard and forced subway builders to brace sections of the tunnel.

Don Miner, deputy construction manager for Parsons-Dillingham, which is overseeing building of the subway, said experts were still assessing the cause of the problems.

Some water pipes may have been ruptured by the Northridge earthquake, he said. “We’re gathering information to find out exactly what transpired,” he said.

“The subsidence was anticipated to a certain degree,” said MTA spokesman Bill Heard. “What could not be anticipated was the saturated area.”

The MTA has put together a “water search team” to look for all the leaks. A spokesman for the city Department of Water and Power said Monday that the leaks appear to be “coming from a number of leaks in service lines.” Repairs are the responsibility of the water customer, she added.

“Responsibility for all these things will have to be sorted out,” Heard said. But the MTA spokesman acknowledged that the initial subsidence was caused by tunneling and added, “We’re not trying to dodge anything.”

Officials took steps to brace the tunnels. “My impression is that the stabilization . . . is apparently working,” said Kim Kimball, the MTA’s deputy chief executive officer who took aides of Mayor Richard Riordan on a tour of the tunnel Monday.

Thursday, workers noticed that the wooden wedges supporting the concrete tunnel liners were compressed, apparently squeezed from above. To shore up the tunnels, workers have installed horizontal and vertical steel beams.

Kimball said he saw some water dripping in the tunnel but added, “I didn’t see anything I would consider abnormal water flow. That’s comforting.”

“The other part that is comforting is that we have not had any more subsidence at the surface level,” he said.

MTA’s response failed to satisfy Los Angeles County Supervisor Mike Antonovich, who Monday called for an investigation into the subway construction.

After shopkeepers on Hollywood Boulevard complained about cracks in buildings, work was suspended Thursday on the $1.5-billion second leg of the subway that eventually will connect Downtown Los Angeles to the Valley.

Sections of the Walk of Fame also buckled and cracked, and celebrities’ stars were removed over the weekend from sections of damaged sidewalk.

A multi-block section of Hollywood Boulevard was closed Saturday afternoon. Many stores along the closed-off stretch remained shuttered until the street was reopened Monday afternoon.

MTA officials have been accepting claims from business owners seeking to recover repair costs or economic losses. Some owners complained that they were unable to get an explanation for the damage.

“Nobody knows anything,” grumbled Elias Khoury, owner of Georgio’s Famous Pizza, pointing to cracks in his building.

Khoury said he lost $1,200 in business; the restaurant had no gas or water, and water damage had rippled the floor. “The whole floor is like a roller coaster,” he said.

A Sinking Street Several blocks of Hollywood Boulevard were reopened Monday after the earth above an unfinished Metro Rail tunnel sank-by as much as nine inches in one spot. Officials are still trying to determine what happened. *1. Workers are digging two subway tunnels about 40 to 50 feet beneath Hollywood Boulevard. 2. Between the street and the tunnels is a layer of loosely packed, sandy soil, saturated with water. There are broken water lines nearby, but it is unclear when they ruptured. 3. A combination of wet, sandy earth and excavation apparently caused the sinkage. 4. On Thursday, workers noticed that the wooden support wedges in the ceiling of the north tunnel were compressed, apparently squeezed from above. They closed the tunnel. 5. Over the weekend, the street began to sink noticeably, leading to its closure. 6. Workers are now shoring up the north tunnel with steel and wood bracing every four feet. Sources: MTA Researched by NICHOLAS RICCARDI / Los Angeles Times