High Bridge

High Bridge, located about one third of a mile below the Washington Bridge, was completed in 1849, and is a portion of the old Croton Aqueduct, carrying the water across the valley of the Harlem River. it extends from One hundred and Seventy-fifth Street and Tenth Avenue to Aqueduct Avenue.

Various schemes were proposed for the aqueduct at this point, and in 1837 a contract was actually let and work started on a rock fill, with an arch at the centre eighty feet wide and thirty feet high, the intention being to lay the water-pipes on top of the embankment and cover them with earth.

The government, however, seeing that such a structure would prove an effectual bar to the further improvement of the river as a navigable stream, refused to permit the continuance of the work, and caused the construction of the bridge as it now stands. it has a total length of 1450 feet, made up of 15 semi-circular arches, 8 of which are of 80 feet and 7 of 50 feet spans. The bridge is about 25 feet wide, and provided with a pathway for foot passengers, but has no provision for vehicles. The arches at the crown give a clear height of 100 feet above high water.

The Croton water is carried in three large pipes built in brick masonry. Two of cast iron, each three feet in diameter, were laid first, but were soon found to be of insufficient capacity. Between 1860 and 1864 the Croton Aqueduct Commissioners raised the side-walls of the bridge and laid a wrought ion pipe, 7 feet 6 inches in diameter, over the other two. The new Croton Aqueduct crosses under the river just north of this bridge. The bridge was built by the city at a total cost of $963,428.

Washington Bridge

The Washington Bridge, extending from One Hundred and Eighty-first Street and Tenth Avenue on the west to Aqueduct Avenue on the east, is one of the most notable structures crossing the Harlem, both in appearance and in form of construction. The two main spans are parabolic steel arch structures, each of six parallel ribs. These ribs are built up of immense voussoirs of steel, forming sections analogous to the ring-stones in a masonry arch. These sections are constructed in the form of an "I" beam, the flanges of the beam being made up of a number of plates, while the web is a single piece. They are each 13 feet in depth. The ribs rest on steel pins, 18 inches in diameter, placed at the springing point of the arch, and supported on pillow blocks carried by the abutments. The arches spring from granite piers, which are carried up to the level of the floor system. This floor is supported by latticed posts resting on the arched ribs, and is a little higher than the crown of the arches.

The principal dimensions of the bridge are as follows: Total length, 2375 feet, made up of the two steel arches, each 510 feet long, the eastern approach of four masonry arches making 342 feet, and a solid fill between granite walls about 325 feet long, and the western approach of three masonry arches 277 feet long, and a solid fill as on the east side of about 411 feet. The clear height of the main arches above high water is 133 feet. The roadway, which is paved with asphalt, is 50 feet wide and the sidewalks each 15 feet. The piers rest on caissons which are carried down to solid rock. There are 40,000 cubic yards of dressed granite and gneiss, and about 14,750,000 pounds of iron and steel in the structure.

The bridge is hoped by engineers to help solve the problem of the relative value of steel and masonry construction, as both forms are used in it. The masonry arches are, of course, much smaller, but the effects of time on each will be carefully noted.

The commissioners appointed to build the bridge asked for competitive designs, and offered prizes for them__$1500 to the best, and $1000 to the second best. The first prize was won b y C.C. Schneider, and the bridge was built on almost the lines shown in his design. The bridge was two years in building, and was opened to the public use in 1889. It cost $2,851,684.

Broadway Bridge

The Broadway Bridge over the Harlem ship canal, connecting the old Kingsbridge Road on the south with Broadway on the north, was commenced in April, 1893, and completed in December, 1894. it has a total length of 551 feet, made up of the two approaches and a swing draw.

The draw span is 265 feet long, giving a clear channel on each side when open of about 85 feet. The bottom chord of the draw is 26.5 feet above high water.

The roadway is 50 feet wide, and the sidewalks 8 feet, both paved with asphalt. The centre piers, abutments, and masonry on the approaches are of granite. The bridge was built at a cost of $450,000.

Spuyten Duyvil (Railroad) Bridge

The present bridge of the N.Y. Central & Hudson River R.R. at Spuyten Duyvil Creek, is a low structure of wood and iron. it has a swing draw 1 4/10 feet above high water, which gives a clear opening of 26.2 feet on each side when open. This bridge was authorized in 1846.

Preliminary surveys and soundings have been made with reference to a new bridge to comply with the law, but nothing definite has been decided upon as yet.

Broadway Bridge, Spanning Spuyten Duyvil Creek

A contract was awarded June 14, 1897, to Messrs. Gildersleeve & Smith, for the construction of a bridge over Spuyten Duyvil Creek at Broadway, to replace the old bridge. Total cost, $53,607.50

Willis Avenue Bridge: (Proposed)

As before stated, the plans for a new bridge to span the river from Willis Avenue to 1st Avenue, have been approved, and the contract will shortly be under way.

The plans provide for a swing draw 310 feet long, giving 108 feet clear opening on each side, and having a height above high water of 24 feet. The southern approach will be 585 feet long, made up of a masonry incline, from 125th Street and 1st Avenue 345 feet long, and a truss 240 feet long from the end of the incline to the end of the draw. On the north, the incline of masonry will commence at 134th Street and Willis Avenue, extending 200 feet. From this point, there will be a steel viaduct 479 feet long, extending to the draw, and supported on eight sets of steel pillars on masonry and pile foundations. The roadway and sidewalks are to be respectively 40 and 13 feet in width, and will be paved with asphalt. The estimated cost is $1,666,000.
 

End of Article: