I-5 stretch due for repairs was a bust from the beginning
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Some Freeways age well. Others require a little extra care. Then there’s the “boat” of Interstate 5 in downtown Sacramento. Amid controversy Built in the 1960s, the sunken stretch of freeway trouble since it has been opened. Concrete cracks appeared immediately. Since then, the clogged drain pipes and the pavement is almost crumbling. Fearing a flood freeway, state officials last week announced plans for a project earlier this summer to save the mile of interstate worrisome. “With the potential for flooding, we feel we need to go in now,” State Department of Transportation Project Manager Ken Solak said. “The surface is wearing in dire need.” They will partially close I-5 for weeks at a time - risking massive traffic jams - to rip out and rebuild much of the freeway. The project is scheduled to start the last week of May The project area runs from Richards Boulevard on the north to the Highway 50 interchange on the south. But the task cunning lies below ground, where under the freeway dips Capitol Street Mall and P. Engineers call it the “boat section,” where the concrete-encased freeway is pressed in on three sides by muddy groundwater, below the level of the Sacramento River. The lowest portion of the boat is anchored in the mud by numerous 80-foot-long piles. Pressure from pushing water upward over the years has caused extensive pavement cracking. An underground drainage system designed to water suction away is failing. Pipes are so tightly packed with silt “it’s almost as hard as concrete,” Caltrans engineer Erol Kaslan said. Crews and maintenance engineers have applied Patchwork fixes for decades, but most have not taken, Caltrans reports show. Crews will close the freeway in downtown’s northern lanes for an estimated two weeks after the likely Memorial Day weekend and Jazz Jubilee in Old Sacramento. Crews will remove the 9-inch road surface and deep tube, then rebuild the road and drainage system with improved materials. New pumps will be added, with back-flush capability to prevent silting. The north lanes, then will be reopened, and the same tasks will be performed on southbound lanes closed. Each side of the freeway will be closed for a second time a week so crews can lay a waterproof seal on the road surface. Sacramento city officials have talked at times about building a concrete platform over the boat section Sacramento to better connect to its waterfront and create new space for parks, housing and office buildings. That is not part of this project repair. The project will cost estimated at $ 37 million - all for a piece of freeway Caltrans officials Did not want built in the first place. In 1959, amid intense debate on planned road to where the freeway, the state public works director warned that a sunken section near the river as well as unfeasible and would leak. City officials, however, wanted the depressed freeway so it would not block the view of the Capitol building from Tower Bridge, then the entrance into the city. Affections began even before the concrete laid. Ground Water pumping at the construction site caused the walls of the Crocker Museum and several nearby buildings to crack. Museum officials and others sued. Brief forced to pay the state $ 500000 in damages. Cracks began showing up in the seal concrete slab under the road even before the road opened. Crews sealed them with epoxy. In 1980, section flooded the boat to its brim after pumps were halted by a problem at the nearby city’s sewage treatment plant. Drivers had to activate from flooded cars and run the ramps up to safety. Caltrans officials say they believe that episode exacerbated silt buildup in drainage pipes. Disaster nearly struck in the winter of 1983 when the water table abnormally high pressure exerted more on the concrete than it was designed to withstand. A part of the section moved about three-fourths of an inch, officials said. Maintenance crews reportedly parked trucks filled with rocks on the boat to help it weigh down section, Caltrans’ Kaslan said. Engineers purposely came close to the flooding structure to hold it down. Caltrans subsequently pump installed between the river and the freeway to relieve high pressure water during times. In 2000, officials decided major rehabilitation work was needed. In an internal Caltrans analysis, written in 2003, officials noted “faulty construction” as a key of the boat’s problems section. But Kaslan, who helped prepare the report, said that phrase refers to the fact the project had leaks from the beginning, not work or that the design was faulty. “We have a few of these structures around the state and leakage is a big issue,” he said. “The design looks good on paper. Building it is another thing. Overall, the (boat’s section) has been adequate performance.” |