Daily News from New York, New York • 72

It-f ffl Daily News, Monday, August 8, 1983 Alternate routes For QB, and RR passengers trying to avoid the bottlenecks caused by the Manhattan Bridge rehabilitation work beginning today, there are alternatives. Trains on the and line will be operating normally. To accommodate QB and RR riders at Chambers service will run more frequently, and additional cars will be provided for RR trains. The train will use the Montague St Tunnel between Dekalb Ave. and Canal making additional stops at Lawrence St.

and Court St in Brooklyn as well as at the Whitehall Rector St, Cort-landt St and City Hall stations in Manhattan. By CHARLES EATON Displaced straphangers will either have to grin and bear it or use alternate routes to and from Brooklyn for the next 12 weeks as subway trains that use the Manhattan Bridge are diverted from the East River crossing beginning this morning. For the next twelve weeks, service will be disrupted on five lines. For the first six weeks, the QB, and RR trains will be affected, while the last six weeks will see a re routing of the and lines. The 73-year-old East River span has been deteriorating rapidly, according to the State Department of Transportation regional director, John Marino.

"An inspection a short time ago showed that these repairs could "not wait any longer," said Marino. "Any delay might have caused a forced closing of the entire bridge in the future." It is the placement of the subway tracks themselves that are causing the well-publicized problems. The term "torsional deflection" refers to the twisting of the bridge This happens when a train passes over tracks located on the outer edges of the span. THE WEIGHT OF THE heavy steel subway cars causes one side of the bridge to drop as much as four feet while the other side rises correspondingly. "If the four tracks had been placed in the center of the bridge, with the vehicle roadways on the outside, there would be minimum movement in the span and the bridge would not be as far gone as it is today," continued Marino.

The designer of the bridge, Leon Mosieuf, could not foresee the loads that would be carried by his creation almost three quarters of a century later. But the 10-year, $100 million rehabilitation program which is under way should make the span better than ever. "If the price seems Marino said, "try balancing the 10-year tag against the cost of a new bridge across the East River. Conservatively, a new bridge would cost $500 million." The $7 million cost of the present 12-week rebuilding program seems like 1 real bargain when examined next to the other figures. Marino said that the entire bridge could have been shut down to allow work to proceed more quickly-, but "we wouldn't even consider that route.

However sometime down the road, when all of the track work is completed, we will be forced to interrupt auto traffic to begin work on the roadways." WHILE SOME PASSENGERS will simply take the delays in stride, others will be forced to seek alternate routes. William Katz, an 80-year-old Bensonhurst resident who frequently travels into Manhattan on the train, said, "I can walk a couple of blocks over and take the train or I can just take the delays and continue to ride the Express buses and other subway lines will absorb some passengers, while others will take to their cars and still others may swell the ranks of those already riding the illegal van sevices. The delays for the project just beginning are not likely to last later than mid-November. According to Marino, most of the work being done now involves the use of concrete to -strengthen the subway roadbeds. It isn't easy to mix and pour concrete when the temperature drops below about 50 degrees.

Trains that normally use Manhattan Bridge, such as one above, will be diverted for 12 weeks beginning today as span undergoes repairs. I -T? I 'Ail -4.