How tall is whitestone bridge

Until the late s, wooden lightposts adorned the approaches. Here, if anywhere, we have pure, functional architecture. When the bridge opened, it carried four lanes of traffic and two pedestrian walkways between the Bronx and Queens. With its sleek, efficient Art Deco design, the bridge also won acclaim from architects, as well as from Mayor Fiorello LaGuardia: Here, completed, we have one of the many monuments of an industrial country that confronted hardship by creating work.

There she stands in all her beauty, awaiting dedication! During , its first full year of operation, the Bronx-Whitestone Bridge carried approximately 17, vehicles per day. The Tacoma Narrows Bridge in Tacoma, Washington, which employed a steel-plate girder deck stiffening system similar to that found on the Bronx-Whitestone Bridge, collapsed during a windstorm in In the aftermath, the Federal government spearheaded a blue-ribbon commission to investigate the collapse of "Galloping Gertie.

With a deck depth of only eight feet and a main span of 2, feet, the depth-to-main span ratio was Moreover, the deck of the Tacoma span was too narrow. Finally, the side spans of the Tacoma span were too long relative to the main span, and the cables were anchored a considerable distance beyond the side spans. A more favorable ratio may have provided more stability. While Ammann believed that the Bronx-Whitestone Bridge was safe, he was aware that the span was subject to oscillation during high winds.

In an effort to enhance the deck's stability, eight cable stays were installed from the towers to the decks in However, this did not stop the bridge's movement: the span was temporarily closed in when the bridge oscillated during a windstorm.

Under orders from Moses, Ammann oversaw the retrofitting of two foot-high stiffening trusses atop the foot-high longitudinal deck. At the time of the retrofit, the six traffic lanes were widened, and the pedestrian walkways were eliminated. In his autobiography Public Works: A Dangerous Trade , Moses recalled the design modification process as follows: Othmar Ammann kept saying in his best Swiss brogue, "The britch is safe, the britch is safe," and we kept saying, "That doesn't make a damned bit of difference if drivers won't use it.

The first remedial step, in which I never had any confidence, was to install diagonal cables leading from the towers down to the girders on the road. It was like lifting a man up by his suspenders. Cables leading to the tower bases would obviously have had more effect in holding down the roadway, but Army Engineer rules prevented narrowing the horizontal clearance of the navigational channel.

In the end, stiffening the bridge by adding foot-high trusses over the plate girders proved to be the only feasible answers. These huge trusses immediately dampened the vertical motion, but they detracted from the extreme simplicity and airy, gossamer lightness of the entire structure.

The bridge was widened by removing the sidewalks to provide six lanes of adequate width, and the correction of vertical motion appeared to most travelers and observers to be an incident. The stiffening trusses provided an additional level of stability, albeit at a price of aesthetics. Nevertheless, the deck of the Bronx-Whitestone Bridge tended to sway more than most suspension bridges.

On November 12, , the bridge swayed vertically by as much as ten inches during a Nor'easter in which winds gusted as much as 70 miles per hour. The incident closed the span for five hours during the morning rush. Ralph Herman, contributor to nycroads. The Triborough Bridge and Tunnel Authority TBTA had to close the Whitestone Bridge at the height of the morning rush hour because of the abandoned vehicles, as well as obvious concern by the public about the integrity of the bridge.

I also remember the TBTA engineers checked the bridge, then had their public relations people assure the public the bridge was safe. If they didn't have give, they would snap. The reason that motorists noticed the sway today is because they were sitting in stalled cars. They felt it move. They don't notice it much when driving. Between and , the Bronx-Whitestone Bridge was stabilized further when engineers installed a mass damper system. Commonly found in skyscrapers, the mass damper system is designed to protect the span against dangerous oscillations.

The mass damper system uses torsion springs measuring feet long, mass blocks weighing 25 tons each, and multiple disc brakes to disperse more than horsepower. They work independently of outside intervention whenever bridge motion due to wind exceeds a pre-determined threshold. Photos by Jim K. It also proved crucial in the development of similar parkway systems in upstate New York and Connecticut.

For many years, trucks and buses had to enter the Bronx-Whitestone Bridge at ramps near the Bronx and Queens approaches. This was because the Hutchinson River Parkway continued north into the Bronx, while the Whitestone Parkway continued south into Queens. In February , the Whitestone Bridge was given the I designation after the preliminary I and I designations were rejected. To allow for the commercial traffic required for inclusion in the Interstate system, the Bronx and Queens approaches were reconstructed from parkway to expressway standards.

When the Throgs Neck Bridge opened in January , traffic volume on the Bronx-Whitestone Bridge dropped from the pre-Throgs Neck level of 30 million vehicles per year. However, this statistical drop would not last long, and by the 's, volume on the Bronx-Whitestone exceeded its pre-Throgs Neck level. The Bronx-Whitestone Bridge, which today has the 23rd longest main suspension span in the world, carries approximately , vehicles per day AADT.

Design modifications -- specifically, the addition of a Warren truss and diagonal stays -- were made on the bridge to help it better withstand stress from heavy loads and high winds. Photo by Steve Anderson. In recent years, engineers have discovered that the added weight of the stiffening trusses and the thicker concrete roadway have accelerated wear and tear on cables that were not designed to carry such heavy loads.

Upon completion of the project in , the bridge lost 6, tons, or one-quarter of its total suspended weight. The highlights of the Bronx-Whitestone Bridge rehabilitation, which was supervised by Weidlinger Associates, were follows: The heavy steel Warren stiffening trusses, which were a remedial measure taken to stabilize the bridge in the s, were removed during mid-to-late To replace the trusses, new lightweight fiberglass fairings were installed during along each side of the existing plate-girder deck.

The eight-foot-high, wedge-like fairings produce the aerodynamic effect of an airplane wing, allowing the wind to circulate around the deck in effect "slicing" the deck , rather than twist it.

The new deck, which has a three-inch-thick roadway, is 40 percent lighter than the old deck. Construction of the new roadway required closure of one lane of traffic at all times.

A concrete "zipper" was used to regulate traffic flow: three lanes to the Bronx during the morning rush, and three lanes to Queens during the evening rush. The deck replacement was completed in September Similar improvements will be made to the approach roadways at a later date.

There was another incident in August in which a ton steel girder dropped from the side of the Whitestone Bridge, though no one was severely injured. The bridge featured pedestrian walkways as well as four lanes of vehicular traffic, and initially charged passenger vehicles a toll of 25 cents. The 2,foot m center span was the fourth longest in the world at the opening, behind the George Washington Bridge and the double spans of the San Francisco—Oakland Bay Bridge.

At its south end, the bridge was to connect with the new Whitestone Parkway, which led southwest off the bridge to Northern Boulevard. A specialized set of lampposts, the "Whitestone" or Type 41 lamppost, was made for the bridge. The lamppost design was later used in many other projects, though it was no longer being actively installed by the s, and only a few such lamps remained as of [update].

In preparation for the World's Fair, amber street lights were installed on the bridge's approach roads, as well as other key corridors around the city. These lamps were distinctly colored so motorists headed to the fair could follow them while driving.

In , the American Institute of Steel Construction recognized the Bronx—Whitestone Bridge for being the "most beautiful monumental steel bridge completed during the last year". Additionally, two parks were opened following the bridge's completion.

A acre 4. On the Bronx side, the blueprint for Ferry Point Park had been developed in conjunction with the bridge's construction, and additional facilities were added in the early s. It had employed an 8-foot 2. After performing a series of experiments on the bridge's design, Ammann concluded that additional measures to stiffen the Whitestone Bridge were unnecessary.

Even so, the public was scared by the fact that the two bridges were similar in design, and this led to a belief that the Whitestone Bridge might be unstable, as Moses later related. To mitigate the risk of failure from high winds, eight stay cables, two on each side of both suspension towers, were proposed for installation. Planning for the project resumed in September at the end of the war, and a low bidder for the project was announced that November.

The project's primary goal was to reinforce the bridge with trusses, thus ensuring the bridge's stability. The four lanes of roadway traffic were widened to six lanes, with the two additional lanes replacing the pedestrian walkways on each side.

On both sides of the deck, foot 4. The stiffening project was completed in In the late s, the Whitestone Parkway and the portion of the Hutchinson River Parkway between the bridge and the Bruckner Interchange were converted to Interstate Highway standards.

Around this time, the Bronx—Whitestone Bridge was nearing its traffic capacity because it was the easternmost crossing of the East River between the Bronx and Queens. In , to alleviate traffic loads on the Bronx—Whitestone Bridge, construction started on the Throgs Neck Bridge to the east. Soon afterward, the World's Fair resulted in an increase in traffic on the Bronx—Whitestone Bridge. In the long run, use of the bridge continued to grow, and by , there were about 31 million vehicles using the bridge annually.

By , the Bronx—Whitestone Bridge carried 35 million vehicles annually, more than the 33 million recorded in , before the Throgs Neck Bridge had opened as an alternate route.

There had been several plans to build a Long Island Sound bridge east of the Bronx—Whitestone and Throgs Neck bridges to relieve traffic on these crossings, although such a bridge remains unbuilt.

No one was injured, and the abandoned cars were towed away. Officials later stated that the bridge was not in danger of collapsing during the storm. The anchorages, roadways, and drainage were to be repaired during off-peak hours for two years. Actual work took place between December and December As the Throgs Neck Bridge was being repaired simultaneously, this caused major traffic jams at both bridges.

During the renovation, the bridge's expansion joints were replaced by the American Bridge Company, which had originally built the suspension towers. However, in , the sealant around the joints was observed to be deteriorating, necessitating additional repairs.

In , the MTA restored the classic lines of the bridge by removing the stiffening trusses and installing fiberglass fairing along both sides of the road deck.

The lightweight fiberglass fairing is triangular in shape, giving it an aerodynamic profile that allows crosswinds to flow through the bridge rather than hit the trusses. The truss removal project also involved upgrading the lighting systems, including the bridge's lightbulbs and the beacons atop the suspension towers, as well as replacing the sprinkler and electrical systems. In , it was announced that the bridge's deck had to be replaced with a new steel orthotropic deck composed of prefabricated panels.

One lane at a time needed to be closed and replaced, so as to minimize traffic disruptions. During the deck replacement, five lanes were kept open at all times using a movable barrier, with three Bronx-bound lanes during the morning rush hour and three Queens-bound lanes during the evening rush. Other renovations included adding mass dampers to stabilize the bridge deck; repainting the two towers and the bridge deck; and installing variable-message signs.

The deck replacement was completed by However, cracks were soon observed in some of the new panels, and by , cracks had been observed in 66 of panels, necessitating approximately 1, feet m of rib welds. The renovations were intended to extend the Bronx—Whitestone Bridge's lifespan indefinitely. These improvements also accommodated the bridge's high traffic volumes: by , the bridge was being used by an average of , vehicles a day, amounting to 43 million crossings that year.

The Queens and Bronx approaches were replaced in a project that started in As part of the project, each of the approaches' lanes was widened to 12 feet 3. The replacement of the bridge's approaches involved replacing 15 supporting piers and 1, feet m of roadway on the Bronx side, as well as 1, feet m of viaduct on the Queens side, which helped support the wider lanes. During the renovation of that approach, the exit from northbound I to Third Avenue was closed and rehabilitated. International Database and Gallery of Structures.

Google Bot Logout. Bridges and Viaducts. Infrastructure projects. Towers and Masts. Tunnels, Caverns and Shafts. Urban planning. Structure Awards. Historic and Listed Structures. Author Index.

Structure Favorites. Media File Favorites. Company Favorites. Bronx-Whitestone Bridge. Add to Favorites. Data Media Literature. There is a total of 13 media files. Beginning of works: 1 June Completion: 29 April Status: in use. Dimensions main span m length of side spans Description The Bronx—Whitestone Bridge has a 2,foot m main span between its two suspension towers, with the span rising feet 46 m above mean high water.

History Predecessors The idea for a crossing between Ferry Point at Clason Point, Bronx, and Whitestone Point at Whitestone, Queens, was first proposed in by real estate speculators who wanted to develop Whitestone. Increases in traffic In the late s, the Whitestone Parkway and the portion of the Hutchinson River Parkway between the bridge and the Bruckner Interchange were converted to Interstate Highway standards. Participants Design. E-Mail Address. Password lost? Log In. No account yet?

Register here for free! Required Data First Name.