The arduous and tricky task of pumping millions of gallons of water from a flooded underground Loop tunnel system could begin as early as Monday, but officials reported a new flood-related crisis Saturday on a key section of the Kennedy Expressway.
A huge drain about 20 feet beneath the expressway was in danger of collapsing, threatening to flood the 2,000-foot-long Kennedy tunnel known as Hubbard`s Cave. The traffic artery carries more than 200,000 vehicles a day.
Two northbound and two southbound lanes through the area were closed to traffic until further notice, leaving three lanes open in both directions.
”There will be major traffic tieups,” said Illinois Transportation Secretary Kirk Brown, who urged motorists to use other routes or use public transportation when the work week begins Monday.
Meanwhile, officials said Saturday that the news was encouraging at a bustling construction site at the Chicago River and Kinzie Street. Crews there have been trying all week to stop the flow of water into a breach in an underground freight tunnel, a breach that has led to the flooding of numerous Loop buildings.
Workers seeking to seal off the damaged tunnel section by early Saturday had filled two shafts sunk west of the breach with gravel and sandbags. In an operation that ran into the night, they then began to pour tons of concrete into two companion shafts.
A concrete plug poured earlier down a shaft on the east side of the breach ”to the best of our knowledge is holding firm,” said John Kenny, vice president of Kenny Construction Co., the city contractor in charge of the effort.
Measuring devices lowered into the section of the damaged tunnel that is being sealed have shown little if any water movement inside, indicating that the flow from the river has been virtually shut off, officials said.
Crews planned to drill small holes near the plugs on both sides of the breach to apply grouting designed to fill any fissures in the coarse concrete plugs and prevent leaks.
Kenny said that the pumping of the tunnel and Loop buildings could begin Monday, though no exact timetable has been established.
”We definitely want to know that the concrete is set,” he said.
”Right now, I`m like an expectant father,” Kenny said. ”I`m just nervous.”
A team of engineers has been meeting for several days to determine the safe rate of removal of the water, but the pumping operation could take a few weeks to complete, said Avis LaVelle, Mayor Richard Daley`s press secretary.
Removing water too quickly from the 60-mile-long tunnel system and from subbasements of downtown office buildings connected to the system could cause structural damage, officials said.
The Army Corps of Engineers will oversee the water-removal effort under terms of an agreement reached between city and federal negotiators on Saturday after several days of negotiation.
At Hubbard`s Cave, engineers from the Illinois Department of Transportation were monitoring conditions closely, as state police stood ready to close it immediately if the drain pipe beneath it collapsed.
The drain pipe, which is 6 feet wide and 8 feet high, runs near sections of the freight tunnel that were capped off when the expressway was built in the 1950s.
Transportation Secretary Brown said that the tunnel is leaking, saturating the soil and allowing escaped water to exert tremendous pressure on the drain pipe.
When the pipe was inspected in June, it was reported in good condition. But a videotape made on Friday showed serious deterioration, with large cracks in a 20-foot section of the reinforced concrete tube and steady streams of water showering through from outside.
”It looks like a car wash,” said Duane Carlson, head of IDOT`s Chicago- area office.
In an attempt to prevent a collapse, officials allowed the drain to completely fill up to stabilize the pressure being exerted from the outside.
Engineers` computations show that if the pipe collapses, Hubbard`s Cave would fill with 2 feet of water in 40 minutes. The water would rise up to cover the road because it is below the level of the Chicago River.
Officials said they did not know how high the water ultimately would rise if the drain ruptures.
The drain will be emptied at the same time that the freight tunnel system is pumped out, officials said. After that, the drain will be inspected to determine the extent of necessary repairs. Work in the drain could extend lane closures for weeks.
More Top Picks Best Car Amplifiers For Subwoofers
Kennedy regulars have become accustomed to disruptions. A $450 million rehabilitation project began last month, reducing the expressway from a total of 10 lanes to 8 for 7.5 miles from Ohio Street and the Edens Expressway junction.
One positive aspect of the project, given the flooding problem, has been a drop in traffic volume by about 25 percent from its normal level of 270,000 vehicles a day.
If Hubbard`s Cave becomes flooded, southbound traffic will be detoured off the expressway at Ogden Avenue, sent down Ashland Avenue to the eastbound Eisenhower Expressway, then back onto the Kennedy and the adjoining Dan Ryan Expressway.
Northbound traffic will be diverted onto the Eisenhower and Congress Parkway. Motorists then will make their way to north-south thoroughfares such as Lake Shore Drive and Ashland Avenue, coming back onto the Kennedy anywhere north of Hubbard`s Cave.
Hubbard`s Cave stretches between Ohio and Lake Streets.
Meanwhile, parking restrictions on downtown streets imposed last week remain in effect, but police said they would make special provisions for people attending Easter service at churches in the area, said Lt. Bernie McDermott.
”Since church services will be going on at different times during the day, we will make reasonable exceptions throughout the day,” he said, adding that police on hand to control traffic will make sure that only worshipers park.
Those seeking off-street parking will be unable to use the Grant Park South garage. It remained closed Saturday, as crews continued pumping out water that was entering the subterranean structure at the rate of 3,000 gallons a minute.
The downtown flooding began Monday, and the city was declared a federal disaster area several days later.
Saturday night, the Federal Emergency Management Agency announced that it had reached agreement with the city on the details of the aid in a contract that also shifts responsibility for reclamation work from City Hall to the Army Corps of Engineers.
Under the pact, Washington will cover at least 75 percent of city expenses, including the cost of repairing public facilities damaged by the flood and overtime pay for fire, police and other city emergency workers.
The Corps will provide ”technical, construction and other assistance as may be required to stop river water from entering the freight tunnels . . . and to drain the tunnel systems,” FEMA said.
”The most expeditious manner to continue the work is to use the contractor already in place,” Kenny Construction, said Lt. Col. Randall Inouye, commander of the Corps` Chicago district. ”We don`t intend to miss a beat in the smooth transfer of responsibility.”
Other contracts will be awarded for the draining operation once plugging at Kinzie Street is completed, Inouye said in a statement.
The Fire Department and the Corps will monitor water levels and pumping rates, he said.
”There may be requests to building owners to adjust pumping rates to synchronize draw-down in basements and tunnels so that undue stress is not placed on structures,” he said.
Earlier Saturday, Fire Commissioner Raymond Orozco said that building engineers at flooded Loop structures were told to halt or cut the rate of their pumping because it was creating a vacuum in the freight tunnel that had caused the fill in one of the concrete plugs to sink.
Orozco said ”a few people were reluctant” to adhere to the order, so his officers had to use ”powers of persuasion” to get them to comply.
The plug stabilized.
The Corps has called for more than 20 specialists from its offices across the country to assist in the Chicago effort, officials said. About 100 Corps personnel were on the scene Saturday.
In the Loop, 14 buildings that have been without electricity for a week because of the flood may remain in the dark for at least another week, depending upon how quickly the structures can be drained, a Commonwealth Edison Co. official said Saturday.
Restoring electricity could take ”as long as a week after the water goes down, depending on what cleanup is required,” said Bob Mannning, vice president of Edison`s commercial operations.
”We can`t do anything until the water goes down,” Manning said during the utility`s demonstration of a remote-controlled video submarine that could photograph damage to subterranean electrical equipment at affected buildings. Use of the high-tech underwater device, nicknamed Rover, also would allow the utility to determine what type of refurbishments and equipment would be needed to restore full service to the buildings, which serve as the daytime homes to thousands of Loop workers, Manning said.
Donald Petkus, vice president of Edison`s corporate relations, said the utility planned to open a temporary office at Monroe Street and Wabash Avenue on Monday to assist building owners, operators, engineers and tenants who plan to return to work Monday.
”If they have any problems from an electrical standpoint, they can visit us to make it more convenient to them,” Petkus said.