Historic New York bridges in need of major repair

On a clear day, many of New York City's 2,001 bridges look more like grand works of art than utilitarian structures over which million of people ride safely to work every day.

Yet faced with the cumulative effects of age, the lack of adequate maintainance, and funding shortages for structural repairs, some of these bridges are the source of major safety concerns.

Uppermost in the minds of state officials who have responsibility for the repair and safety of these bridges is addressing those problems which could endanger the lives of motorists and pedestrians in the immediate future.

In late June, a Brooklyn Bridge cable snapped, killing one person. Similar cables now are being anchored.

Last year, the outer roadway of the Queensboro Bridge was closed just before it might be collapsed and fallen into the East River, officials told the Monitor.

But these are only relatively "minor" problems plaguing city bridges, according to state officials. Unless something is done about the more serious structural problems, officials say, a few of the most traveled and historic bridges will have to be closed.

Although the state has launched an ambitious, 10-year plan to correct major faults, the plan hangs precariously in the balance in the face of moves to trim federal aid. About 75 to 80 percent of money used to repair and rehabilitate the city's bridges comes from federal coffers.

This comes at a time when "our bridges in general are in poorer structural shape than most of the bridges throughout the state and the country," says George Zaimes, director of engineering and operations for the New York Department of Transportation (DOT), Office of New York City Affairs.

Officials here are hopeful, however, that they can dissuade the Reagan administration from cutting federal bridge rehabilitation funds when legislation comes up for consideration in Congress next year.

Already some favorable political winds have been blowing toward the bridges most in need of repair or replacement. Top administration officials have called the Federal Highway Administration's (FHA) proposed five-year (1982-86) Highway Bridge Rehabilitation and Replacement Program of "major importance" in shoring up deficient bridges. Mr. Reagan's budget analysts have not sought to cut this program, though there is concern within the FHA that it may.

State officials plan to spend more than $1 billion on bridge repair work over the next decade provided the anticipated federal funds (approximately $750 million) are not cut. Nearly $400 million will be spent just on the four East River bridges -- the Brooklyn, Williamsburg, Manhattan, and Queensboro. The Brooklyn Bridge is the nation's oldest suspension bridge; it will be 100 years old in 1983. The others are less known to Americans but are almost as old as grand.

Major structural problems have been found with the following bridges:

* Queensboro. Opened in 1909, the bridge connects Manhattan to the borough of Queens. This bridge carries traffic on two levels. The lower "deck" has seven lanes. Last year, the outer lanes of the lower deck were closed when it was discovered they were in danger of falling from the bridge because of major structural problems. Had the lanes not been closed and repair work begun immediately, "We could have really had a disaster," says DOT's Mr. Zaimes. Even more significant work lies ahead, including rehabilitation of the upper roadway and the inner roadway of the lower traffic deck.

* Williamsburg and Manhattan Bridges. Completed in 1903, sections of the main suspension system of the former are rusting seriously while the steel "floor beams" of the Manhattan Bridge are showing signs of severe cracks. The cracks have developed in part because the bridge was not designed to carry the heavy subway cars it now does. According to officials, the cracks are not yet "unsafe."

In both cases, state officials say, the technology is not currently available to correct these specific problems. However, on-site and laboratory research is being conducted. Zaimes and others are confident answers will be found in the not-too-distant future.

* Brooklyn Bridge. The biggest problem facing engineers is the rust that thas developed at the ends of the main cables anchored on the Manhattan side of the bridge. The bedrock caves containing the steel "eyebeams" to which the cable ends are attached are only three feet high and are impossible to work in. The caves are being enlarged "very carefully," notes John Marino, assistant commissioner for New York City Affairs of the state DOT. Once access to the cable ends is provided, new segments must be spliced onto the main unrusted portion of the cable. Although the technology needed to accomplish this has not yet been developed, it is under comprehensive study. This is believed to be the first time in history this kind of engineering feat has been attempted.

State engineers rank bridges for safety on a scale of 1 to 7. A ranking of 1 constitutes an immediate safety hazard; 2 indicates a "potential hazard"; 3, a serious condition that must be addressed immediately; and 4, a condition that should not be ignored for any length of time.

Mr. Zaimes currently ranks the four East River bridges "between 3 and 4."