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Macombs Dam Bridge

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69-787: The Macombs Dam Bridge ( / m ə ˈ k uː m z / mə- KOOMZ ; also Macomb's Dam Bridge ) is a swing bridge across the Harlem River in New York City , connecting the boroughs of Manhattan and the Bronx . The bridge is operated and maintained by the New York City Department of Transportation (NYCDOT). The Macombs Dam Bridge connects the intersection of 155th Street and Adam Clayton Powell Jr. Boulevard (Seventh Avenue) , located in Manhattan, with

138-615: A swing bridge over the Harlem River, pivoting around a small masonry island in the middle of the river. The swinging span is the oldest remaining swing bridge in New York City that retains its original span. According to the New York City Department of Transportation (NYCDOT), which maintains the bridge, it is the city's third-oldest major bridge still in operation. It is variously cited as being 408 or 415 feet (124 or 126 m) long. It has four lanes for vehicular traffic and

207-485: A connecting road descends from the median of Seventh Avenue, connecting to the lower section of 155th Street. At the eastern end of the over-water span, there are two Warren truss spans, followed by a camelback span over the tracks of the Metro-North Railroad 's Hudson Line . Past the camelback span, the bridge intersects with the on- and off-ramps to and from the southbound Major Deegan Expressway . To

276-509: A dam. In one incident in September 1839, local residents breached the dam over several days, and their actions were later reinforced by New York Supreme Court despite the operator's objections. Following legislature passed by the city in 1858, the dam was demolished that year, and was mandated to be replaced with a swing bridge. The wooden Central Bridge, a swing bridge across the Harlem River, followed in 1860 or 1861. The span's construction

345-552: A gate, but require substantial underground structure to support the pivot. Many inner cities have swing bridges, since these require less street space than other types of bridges. (A "swing bridge" in New Zealand refers to a flexible walking track bridge which "swings" as you walk across.) In the UK, there is a legal definition in current statute as to what is, or is not a 'swing bridge' The largest double swing-span bridge in

414-399: A sidewalk on each side for pedestrians. The roadway measures 40 feet (12 m) wide and the sidewalks measure 9.9 feet (3.0 m) wide. The total width of the deck, including additional space for supports and railings, is 65 feet (20 m). The span's trusswork consists of concave chords running along the top. The chords taper up toward a square section in the center of the span, which

483-480: A tall chain-link fence above. The rest of the viaduct contains utilitarian metal railings and tall chain-link fences. The viaduct was designed similar to a landscaped boulevard or parkway , with observation decks projecting outward from the viaduct's sidewalks. Additionally, four long metal staircases originally connected the viaduct and the lower level of 155th Street; these stairs had canopies covering their upper flights. By 1992, only two of these stairs remained on

552-402: A vertical locating pin and support ring, usually at or near to its center of gravity, about which the swing span (turning span) can then pivot horizontally as shown in the animated illustration to the right. In its closed position, a swing bridge carrying a road or railway over a river or canal , for example, allows traffic to cross. When a water vessel needs to pass the bridge, road traffic

621-736: A viaduct connecting the high point of Coogan's Bluff to the Central Bridge. Around the same time, the Central Bridge was slated to be rebuilt as a result of the River and Harbor Act, passed by the United States Congress in 1890. As part of the act, bridges on the Harlem River with low vertical clearance were to be replaced with those with at least 24 feet (7.3 m) of clearance during mean high water springs . Drawbridges and swing spans were determined to be most suitable for this purpose. Structural engineer Alfred Pancoast Boller

690-566: Is 2,540 feet (770 m), including its approach viaducts. As of 2019, the Macombs Dam Bridge carries New York City Transit 's Bx6 and Bx6 SBS bus routes. In 2016, the New York City Department of Transportation reported an average daily traffic volume in both directions of 38,183, with a peak of 55,609 in 1957. Between 2000 and 2014, the bridge opened for vessels 32 times. The Macombs Dam Bridge includes

759-419: Is a logical and sometimes privileged area for the use of high-performance concrete. High-performance concretes are manufactured by reducing the porosity of the concrete, which means reducing the ratio E/C of the mass of water to that of cement per 1 m3 of concrete. A ratio E/C below 0.4 generally corresponds, with common cements, to the domain of HPC (the strength then exceeds 50 MPa). In practice, to overcome

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828-409: Is considered tall when it exceeds 70 m. The slenderness, the ratio of the maximum diameter of the shaft to the height of the pile, is generally less than or equal to 1/10°. The compression exerted at the base of the pile is accentuated both by the weight of the pile itself and by the weight of the supported deck, as tall height generally combines, for architectural reasons, with long span. Therefore, this

897-473: Is stopped (usually by traffic signals and barriers), and then motors rotate the bridge horizontally about its pivot point. The typical swing bridge will rotate approximately 90 degrees, or one-quarter turn; however, a bridge which intersects the navigation channel at an oblique angle may be built to rotate only 45 degrees, or one-eighth turn, in order to clear the channel. Small swing bridges as found over narrow canals may be pivoted only at one end, opening as would

966-426: Is the third-oldest major bridge still operating in New York City, and along with the 155th Street Viaduct, was designated a New York City Landmark in 1992. The Macombs Dam Bridge was named after Robert Macomb , the son of merchant Alexander Macomb . It is composed of an over-water span and the 155th Street Viaduct, both of which were designed by consulting engineer Alfred Pancoast Boller . The bridge's total length

1035-494: Is topped by four finials . On the Manhattan side, there is a plaque stating the year 1894, the words "Central Bridge", and the name of the bridge's major engineers. The design has been compared to a "raffish tiara" due to the presence of the Gothic Revival -style abutments. The swing span can be rotated around a tower located below the center of the deck, which in turn is located on the small masonry island. On both sides of

1104-507: The United States Congress moved to ban tolls on these bridges. A new interchange on the Bronx side opened in 1977, providing easier access to Yankee Stadium. The same year, jurisdiction passed to the NYCDOT, which still operates and maintains the bridge and viaduct. By 1988, the NYCDOT listed the Macombs Dam Bridge as one of 17 bridges citywide that urgently needed restoration. The work, initially expected to cost $ 34 million, would pay for

1173-491: The Harlem [...] which warrants a walking tour". After Boller's death in 1912, a colleague wrote that the Macombs Dam Bridge was one of several spans designed by Boller that were "characterized by their originality and boldness of design". The painter Edward Hopper depicted the bridge in a 1935 painting of the same name . Boller designed several bridges across the surrounding section of the Harlem River. Two of them were built to

1242-466: The Hooper Fountain after its donor, businessman John Hooper—still exists on the southeast corner of the 155th Street Viaduct and Edgecombe Avenue. Just east of the column, a path leads south to Jackie Robinson Park . Before the viaduct was built, the 155th Street station of the elevated IRT Ninth Avenue Line , located along Eighth Avenue at the bottom of the cliff, could only be reached from

1311-544: The Macombs Dam Bridge was "the most pretentious and costly" of the Harlem River swing bridges, and that the Macombs Dam and University Heights Bridges were "highly creditable works, in an artistic as well as in a scientific sense." The writer Sharon Reier, in the book "The Bridges of New York", referred to the Macombs Dam Bridge and the University Heights Bridge as "the only movable bridge[s] across

1380-551: The Manhattan borough president's office in 1898. A trolley franchise was awarded to the Union Railroad Company in 1903, providing Bronx residents with a direct connection to the Eighth Avenue trolley. The first trolley traveled over the Macombs Dam Bridge in 1904. Due to the increasing prevalence of trolleys and automobiles, there was a decrease in horse-drawn carriages that used the bridge. Also in 1904,

1449-471: The United States is the 3,250 feet (990 m) long, 450 feet (140 m) navigable span, 60 feet (18 m) clearance George P. Coleman Memorial Bridge . Omaha NE Turn Style Bridge is now a historical landmark. Located 86H674H5+98 Used for rail transport. Connecting Council Bluffs, Iowa to downtown Omaha, Nebraska Bridge pier The pier of a bridge is an intermediate support that holds

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1518-420: The approach road is 1%. The original river crossing on the site was called Macombs Dam and was built along with the since-demolished lock-and-dam system on the Harlem River. The dam was opened in 1814, and the bridge was finished in 1815 or 1816. Macombs Dam's capacity was limited by its narrow width, as the manned lock only measured 7 by 7 feet (2.1 by 2.1 m), and by the mid-19th century, no longer used as

1587-498: The approach viaducts and the four ramps to and from the Major Deegan Expressway. The over-water span was also repainted and the electrical systems were replaced. Simultaneously, the NYCDOT also assessed the Macombs Dam Bridge and 155th Street Viaduct for a seismic-retrofitting project, which at the time was slated to be completed between 2010 and 2013 for $ 36 million. Despite the low probability of earthquakes in

1656-578: The approach's southern side, which are carried by box girders. Part of the approach ramp is carried on an abutment pier, which contains a limestone-and-granite facade. A stairway leads from the Seventh Avenue approach's western sidewalk to the lower level of 155th Street; a corresponding stair on the eastern sidewalk of Macombs Place was demolished when the Seventh Avenue ramp was rebuilt in 1930. As originally laid out, Macombs Place provided access to Eighth Avenue (Frederick Douglass Boulevard) , which

1725-504: The area, the project had been proposed after more stringent building codes had been implemented in 2003. Even while under construction, the Macombs Dam Bridge and the 155th Street Viaduct were favorably appraised by contemporary media. Scientific American praised the design of the ornamental iron handrails and lampposts in 1890. Two years later, the Engineering News-Record said that the two structures comprised "two of

1794-539: The bridge was officially renamed with its original moniker in 1902. The 155th Street Viaduct and over-water span were formerly operated by two different entities. The over-water span was erected by the New York City Department of Parks and Recreation before being transferred to the Bridge Department in 1898, while the 155th Street Viaduct was erected by the Department of Public Works and was transferred to

1863-559: The bridge, connecting with the IRT Jerome Avenue Line (current 4 train). The bridge opened in 1880, and was demolished after that portion of the Ninth Avenue line stopped operating in 1958. Notes Citations Sources Swing bridge A swing bridge (or swing span bridge ) is a movable bridge that can be rotated horizontally around a vertical axis. It has as its primary structural support

1932-462: The bridge. Two are from the Manhattan side (the 155th Street Viaduct and the Seventh Avenue approach), while the third leads to the intersection of Jerome Avenue and 161st Street in the Bronx. At the western end of the over-water span is a long steel viaduct, carrying two sidewalks and two lanes of traffic in each direction. The viaduct stretches from the intersection of 155th Street , Edgecombe Avenue, and St. Nicholas Place, at its western end, to

2001-498: The construction of increasingly daring and economical structures. Paul Séjourné would be the last great theorist of masonry bridges, and his methods and formulas for calculating piers remain relevant today. Piers then became more slender and taller. As early as 1937, considerable height was reached with the Golden Gate Bridge in the United States, which has pylons 230 meters tall. A further leap forward occurred with

2070-436: The deck of the structure. It is a massive and permanent support, as opposed to the shoring , which is lighter and provides temporary support. Until the advent of concrete and the use of cast iron and then steel, bridges were made of masonry. Roman bridges were sturdy, semicircular, and rested on thick piers, with a width equal to about half the span of the vault . It was only from 1750, with Jean-Rodolphe Perronet , that

2139-670: The decrease in workability of the concrete due to low E/C ratios, superplasticizers are used to deflocculate the fines (cement, mineral additions, ultra-fines). The composition of the HPC80 concrete used for the Elorn Bridge was as follows: Two construction methods can be used to build tall piers: Structures with the tallest piers in the world are concentrated in Europe, specifically in France, Germany, and Austria. The first of these

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2208-435: The emergence of two new technologies: pre-stressed concrete developed by Eugène Freyssinet in 1928 and high-performance concrete in the 1980s. The combination of the two allowed for the construction of very tall piers. In masonry bridge piers, there is a resistant part and a filling part: The dimensions of the supports result from the consideration of four criteria: stability against overturning, compression resistance of

2277-450: The existing Central Bridge. In 1877, the swinging component's square-shaped frame was removed and an A-frame was installed. The approach spans were subsequently replaced with iron in 1883, and the wooden span was rebuilt in 1890. The rebuilt span was 210 feet (64 m) long and 18 feet (5.5 m) wide, with two 4-foot-wide (1.2 m) sidewalks, as well as approach ramps measuring 180 feet (55 m) long. These improvements did not help

2346-470: The foundations for the over-water span. A caisson was used for the western bank's pier and the central pivoting "island", while a cofferdam was used for the eastern bank's pier. The latter required a modification to the original contract "owing to the great depth of swampy bottom". The design of the short span over the Hudson Line railroad tracks was likely also changed when the contract modification

2415-542: The illustration opposite. Columns, being visible surfaces, are often subject to architectural research. This can result in a different section from the classic disk or specific surfaces. This is called architectural concrete. Some structures have pile forms different from these two classic forms of column or wall. The deck of the Europe Bridge in Orléans is supported by particularly original tripodal piers. A pile

2484-408: The intersection of Jerome Avenue and 161st Street , located near Yankee Stadium in the Bronx. The 155th Street Viaduct, one of the bridge's approaches in Manhattan, carries traffic on 155th Street from Seventh Avenue to the intersection with Edgecombe Avenue and St. Nicholas Place. The bridge is 2,540 feet (770 m) long in total, with four vehicular lanes and two sidewalks. The first bridge at

2553-438: The intersection of Macombs Place, Macombs Dam Bridge, and Seventh Avenue (also Adam Clayton Powell Jr. Boulevard) at its eastern end. There are traffic lights at both ends of the 155th Street Viaduct. An unconnected lower section of 155th Street runs at ground level under the viaduct. The viaduct stretches 1,600 feet (490 m) was built due to the presence of Coogan's Bluff at its western end, some 110 feet (34 m) above

2622-452: The island are shipping channels with 150 feet (46 m) of horizontal clearance. When closed, the bridge provides 25 feet (7.6 m) of vertical clearance. The swinging portion weighs 2,400 short tons (2,100 long tons; 2,200 t) and is turned by two concentric drums: the inner drum has a diameter of 36 feet (11 m) and the outer has a diameter of 44 feet (13 m). At the time of its construction, Macombs Dam Bridge's over-river span

2691-421: The line of view between Seventh Avenue and the bridge, so the builders decided to destroy the rock. The city also acquired land for a park between Macombs Dam Road, Seventh Avenue, and 153rd Street. Additionally, there were problems in coordinating work on the viaduct and over-water span, since the two segments intersected at an angle. An additional contract for a second Bronx approach from Sedgwick and Ogden Avenues

2760-509: The northeast, a steel approach road leads to Jerome Avenue, which extends north into the Bronx and Westchester County , and there are cloverleaf ramps to and from the northbound Major Deegan Expressway. The approach road consists of six steel-and-concrete spans across the expressway, as well as six more Warren trusses. These spans are supported by girders located atop granite piers. The approach road contains another intersection, with 161st Street, before terminating at Jerome Avenue. The grade of

2829-449: The old drawbridge was floated slightly north to 156th Street while the new span was constructed immediately adjacent. The old bridge remained there until the new span was completed, at which point the old span was demolished. After the height of the over-water span's deck had been established, two falsework rails were placed on the outer edges of the span, along which a rolling scaffold traveled. Two different methods were used to construct

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2898-415: The over-water span cost $ 1.3 million (equal to $ 48 million in 2023); however, the total cost of the over-water span including land acquisition was $ 1.774 million (about $ 65 million in 2023). The new bridge was also called the Central Bridge, and though a plaque bearing this name still can be seen on the swing span, the name never stuck. The old "Macombs Dam" name remained in popular use, and

2967-466: The over-water span that November; the plans entailed a smaller approach viaduct in the Bronx to cross over the swamp on that side. Work on the 155th Street Viaduct began in December 1890. At the end of 1891, the foundations for the 155th Street Viaduct's support structure, as well as the masonry abutment at the viaduct's western end, had been constructed. However, further work at the viaduct's east end

3036-562: The parts of a grand system of improvements which will [...] transform that section of the city of New York." In 1895, after the bridge was completed, the Real Estate Record called the bridge "a beautiful piece of engineering work splendidly conceived." Bridge engineer Martin Gay praised the masonry's "fine lines" and the "graceful sweep" of the over-water span's upper chord in 1904. Architectural critic Montgomery Schuyler stated that

3105-400: The pedestrian railing was damaged in 1949 after a boat's boom ran into the over-water span. Around the same time, from 1949 through 1951, the approach to Ogden and Sedgwick Avenues in the Bronx was demolished to make way for the construction of the Major Deegan Expressway. Three segments of truss bridge were also removed during this time, and the removed truss segment over the expressway's path

3174-436: The piers at the level of the vault spring lines is given by the formulas of Paul Séjourné . In this case, the height of the structure, measured between the top of the deck and the ground, is between the values a/3 and a/2, where a denotes the span of the arch, which is generally a semicircular or elliptical arch. The thickness e of the pier depends solely on the span of the arches: a/10 < e < a/8. The total height of

3243-586: The piers of the Fades viaduct in France, inaugurated on 10 October 1909, are the tallest traditional masonry piers ever built. Considerable progress was then made with the invention of modern natural cement discovered in 1791 by James Parker in England and especially through the work of Louis Vicat in France (1813–1818) who laid the foundations of the hydraulic binders industry and thus of concrete. The alliance with steel gave birth to reinforced concrete, allowing

3312-517: The public's reputation of the bridge, and one driver was quoted as saying, "They ought to keep it for clam wagons, though no clam with any regard for himself would ever cross the bridge." By the late 1880s, landowners in Upper Manhattan were advocating for development of Washington Heights , the then-sparsely-populated area atop Coogan's Bluff, the high cliff to the west of Macombs Dam. At the time, there were few options for traveling between

3381-425: The restoration of steel brackets and deteriorated concrete supports. The New York City Landmarks Preservation Commission designated the Macombs Dam Bridge and the 155th Street Viaduct as a city landmark on January 14, 1992. The NYCDOT conducted a $ 145 million overhaul of the bridge between 1999 and 2004. As part of the renovation, the NYCDOT replaced the deck of the bridge, and renovated the structural elements of

3450-447: The river. It passes over an unconnected section of 155th Street located at the bottom of the cliff. The viaduct is supported by 31 girders; the western 22 girders contain horizontal, diagonal, and vertical bracing, while the eastern 9 girders do not contain bracing. The extreme western end of the viaduct is located on a granite and limestone abutment; the roadway retains its original ornamental iron railings designed by Hecla Iron Works, with

3519-491: The site was constructed in 1814 as a true dam called Macombs Dam . Because of complaints about the dam's impact on the Harlem River's navigability, the dam was demolished in 1858 and replaced three years later with a wooden swing bridge called the Central Bridge, which required frequent maintenance. The current steel span was built between 1892 and 1895, while the 155th Street Viaduct was built from 1890 to 1893; both were designed by Alfred Pancoast Boller . The Macombs Dam Bridge

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3588-656: The south of the Macombs Dam Bridge. These spans were the 145th Street Bridge and the Madison Avenue Bridge , which originally opened in 1905 and 1910, respectively. Though the 145th Street Bridge was replaced in 2006, writer Sharon Reier had described the original 145th Street Bridge as an "uninspired copy" of the Macombs Dam Bridge. Immediately to the north of the Macombs Dam Bridge was the Putnam Bridge , also designed by Boller. The New York City Subway 's now-demolished Ninth Avenue elevated line ran over

3657-404: The steam engine that powered the movable over-water span was replaced with a 24 horsepower (18 kW) electric motor, which itself was replaced with a 52 horsepower (39 kW) motor in 1917. The New York City Department of Plant and Structures assumed control of the over-water span in 1916, and five years later it also had jurisdiction of the 155th Street Viaduct. In 1920, while Yankee Stadium

3726-698: The structure is generally between 1.5 a and 2.5 a. The arches are semicircular, and their thickness T depends both on the span a of the arches and on the height H of the structure: If H = 2.5 a, T = 0.1 a + 0.04H If H < 2.5 a, T = 0.125 a + 0.04H However, if the span a is small (a<8 m), it is preferable to use the following formula for T: T = 0.15 a + 0.4. Most of the piers of modern bridges are made of reinforced concrete or prestressed concrete for larger structures. Two types of forms are mainly encountered: columns or walls. Each support can be composed of one or more walls or columns. The standard-shaped walls that can be found on most highways are represented in

3795-512: The support masonry, permissible pressure on the ground, and aesthetics. However, the piers of the first bridges were not calculated, and the characteristics of the structures resulted from empirical formulas. The piers of the early structures were very robust to ensure the stability of the support during construction: each pier was self-stable under the thrust of the already built vault. Subsequently, technical evolution, such as simultaneous vault construction, allowed for refinement. The thickness of

3864-411: The thickness of the piers could be reduced. While it was considered an absolute rule to give them a thickness equal to one-fifth of the span, Perronet proposed and succeeded in having thicknesses equal to one-tenth of the span and rises varying between one-fifth and one-seventh accepted. These reductions significantly reduced the obstacle to water flow created by the structure. With a height of 92 meters,

3933-525: The top and bottom of Coogan's Bluff. Another reason for developing this region of Manhattan was the opening of the Polo Grounds stadium at the bottom of Coogan's Bluff in 1890. By 1886, local landowners had come to an agreement that a viaduct was needed to connect the top of Coogan's Bluff and the Central Bridge. The next year, the New York state legislature passed a law that enabled the construction of

4002-431: The top by a long staircase. A Scientific American magazine article in 1890 stated that "To draw a load up the hill a team has to be taken a mile or more to the south". The other approach viaduct to the over-water span is from Seventh Avenue and Macombs Place (formerly Macombs Dam Road). It is 140 feet (43 m) long. The approach ramp is carried by several steel plate girders , as well as three Warren truss spans on

4071-401: The west side of Eighth Avenue, and by 2000, both remaining stairs had deteriorated too severely to be restored. On the western end of the viaduct, a stone staircase connects the north sidewalk of the viaduct and the lower section of 155th Street. A 28-foot-tall (8.5 m) column with a weather vane , lamp, and drinking fountain is at the western end of the viaduct. The fountain—sometimes called

4140-660: Was delayed until the over-water span's foundations could be laid. The contract for the over-water span and Bronx approach was given to the Passaic Rolling Mill Company in March 1892, and work on that segment began two months later. The contractors and suppliers for the 155th Street Viaduct were also contracted for the over-water span. As the old bridge was about to be closed, residents of the town of Tremont, Bronx , expressed concerns that one of their few links to Manhattan would be temporarily severed. Ultimately,

4209-624: Was designed by Boller in January 1893, and was approved by the New York State Legislature . In 1894, the contract for the second Bronx approach was awarded to Passaic, while the contract for the over-water span's ornamentation was given to Valentine Cook & Son. The 155th Street Viaduct opened on October 10, 1893. The over-water span opened "without any particular ceremony" a year and a half later, on May 1, 1895. The viaduct cost $ 739,000 (about $ 25 million in 2023), while

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4278-526: Was hired to design the viaduct; his plans were officially approved in May 1890 at an estimated cost of $ 514,000, to be split evenly between the city and landowners. The city hired Herbert Steward to be the contractor; the Union Bridge Company for structural steel; and Hecla Iron Works for iron ornamentation. In June 1890, Boller was also hired for the over-water span. Boller submitted his plans for

4347-416: Was initially supposed to cost $ 10,000, but ultimately cost nine times as much. The wooden swing bridge included a rotating square tower situated atop a small island in the center of the river; the span itself was supported by iron rods attached to the tower. Because of the number of wooden parts, it often required maintenance. The city held a contest in 1875 for the installation of "a new wooden draw" to replace

4416-416: Was located at the bottom of Coogan's Bluff and was bypassed by the viaduct. Original plans did not provide for a connection to Seventh Avenue, but a curved ramp to Seventh Avenue was added by the time the bridge was opened. The approach was rebuilt in 1931 to provide direct access to Seventh Avenue. As of 2020, it provides access to southbound Macombs Place and both directions of Seventh Avenue. At 152nd Street,

4485-399: Was made. By late 1892, the 155th Street Viaduct was nearly completed and the Real Estate Record stated that pedestrians were already using the viaduct to access the elevated line. However, there were disputes over the ramp between Seventh Avenue and the over-water span. In the initial plans, the 155th Street Viaduct lacked a direct connection to Seventh Avenue. A rocky outcropping obstructed

4554-408: Was opened in 1931. The approach was built on land donated by John D. Rockefeller Jr. The new approach, designed by Andrew J. Thomas , entailed rebuilding the formerly-straight Macombs Dam Road approach to a "flared polygonal" route, which required extending the masonry abutment there. In 1938, both the over-water span and the viaduct became the jurisdiction of the Department of Public Works. Part of

4623-518: Was replaced with a new steel deck. The trolley tracks were also removed c.  1950 , and many of the original decorative and lighting fixtures were replaced in the early 1960s. The Transportation Administration assumed control of the bridge and viaduct in 1966. Mayor John Lindsay proposed enacting tolls along the University Heights Bridge, as well as all other free bridges across the East and Harlem rivers, in 1971. The proposal failed in 1977 after

4692-464: Was said to be among the largest drawbridges built to date, or the heaviest movable mass in the world. On either bank of the river are pairs of stone end piers with shelter houses. The shelter houses contain red tile roofs and are used by the bridge tender . Latticework gates are located near these end piers, blocking off access to the span when it is in the "open" position. Many of the original railings have been replaced. There are three approaches to

4761-447: Was under construction, ramps were built on the Bronx side of the Macombs Dam Bridge, leading to 161st Street. As part of this project, the staircase on the northern facade of the Bronx abutment was demolished, and a corresponding stair on the southern facade was built. On the Manhattan side, a rebuilt approach from Seventh Avenue and 151st Street to the bridge, as well as a rebuilt triangular plaza between Seventh Avenue and Macombs Dam Road,

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