GAS AND WATER MAINS.

A rearrangement of the gas pipes in the three streets crossing the

Terminal site was necessary. These pipes were of two classes: trunk

mains and service mains. Fortunately, there were but two trunk mains

in the three streets, one a 20-in. in 31st Street from east of Seventh

Avenue to Ninth Avenue, the other a 16-in. in 32d Street from east of

Seventh Avenue to Eighth Avenue. The 20-in. main was relaid from Seventh

Avenue and 31st Street down Seventh Avenue to 30th Street and through

that street to Ninth Avenue. The 16-in. main was relaid from Seventh

Avenue and 32d Street north to 34th Street and through that street to

Eighth Avenue. The service mains in 32d Street were no longer required,

and were taken up and not replaced. The houses on 31st and 33d Streets

were provided with service by two 6-in. wrought-iron mains back of the

retaining walls in each street, that location being chosen to avoid

damage by gas drip to the water-proofing of the street bridges. As the

permanent structures under the avenues were not to approach the surface

nearer than 19 ft., only slight rearrangements, sufficient to permit the

new sewers and water lines to be laid, were necessary.

There were no large water mains to be cared for, in fact, those in the

streets were too small for ample fire protection, being only 6 in. in

diameter. The main in 32d Street was taken up and not replaced, and

those on 31st and 33d Streets were replaced by 12-in. pipes laid back

of the retaining walls. No changes were necessary in the mains in the

avenues, but, before approving the rearrangement for the streets, the

Department of Water Supply, Gas and Electricity added a 48-in. main in

Eighth Avenue to be laid as a part of this construction, the pipe being

supplied by the City.

Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 The Site of the Terminal Station. Paper No. 1157 · 第 5 / 12 题