from east of Seventh Avenue and south of 34th Street. It was decided to
build this sewer of cast iron where it crossed the proposed construction
work, and also to replace with cast iron the brick sewers on 31st, 32d,
and 33d Streets from Seventh Avenue to a point east of the west end of
the standard tunnel section, and also the sewer on Eighth Avenue from
the north side of 33d Street to the south side of 31st Street. This
arrangement permitted: first, the removal of the sewer in 32d Street
between Seventh and Eighth Avenues, which was necessary, as that street
was to be excavated; second, the reduction of the sewer in Eighth Avenue
from a 6-ft. to a 5-ft. circular conduit; and, third, assuming that the
sewage and drainage from the Terminal would be pumped directly to the
sewers in the avenues, the reduction of the sewers in 31st and 33d
Streets, from Seventh to Ninth Avenue, to 15-in. vitrified pipes, except
west of the Service Building in 31st Street, to accommodate which
section, a larger sewer was required. The sewer in 32d Street, from
Ninth to Eighth Avenue, of course, could be dispensed with in any
arrangement, as all the area tributary to it was to be excavated.

[Illustration:
Fig. 2.
PLAN SHOWING LAYOUT OF SEWER IN CATCHMENT AREA ABOUT TERMINAL STATION]


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