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The following is an excerpt from a report published by the New York City Transit Authority.
New York City Transit Authority
June, 1973
This report summarizes the engineering studies for Route 132-C of the Second Avenue Subway performed in accordance with the Agreement of February 24, 1972 between the New York City Transit Authority and De Leuw, Cather & Company of New York, Inc. The studies include:
Three different schemes were explored thoroughly, each containing a combination of alignment, profile, construction methods, engineering and construction costs and impact on the environment during the construction period. The final choice, identified herein as the RECOMMENDED SCHEME, contains elements of the other schemes arranged in an optimum combination offering the lowest construction cost consistent with the safety, comfort and convenience of the subway user.
An alignment satisfying the engineering, geologic, economic, environmental and practical demands for a Second Avenue and Water Street Subway has been developed. It is presented herein as the RECOMMENDED SCHEME. It is, of course, an optimum compromise between divergent determinants and represents the choice between various Alternative Schemes documented in detail in Chapter IV.
Route 132-C, the Second Avenue and Water Street Subway, is 3.7 miles long. It extends from Whitehall Street to East 34th Street generally along Water Street, Pearl Street, St James Place, Chrystie Street and Second Avenue north to the interface with Route 132-A in the vicinity of East 34th Street. It will be constructed by cut~and~cover and rock tunneling methods, possibly with a very short section of earth tunneling under air pressure.
Its relationship with other existing and proposed rapid transit lines is shown in Exhibit 1, General Location Map. Route 132-C joins at its northern end with Route 132-A in the vicinity of East 34th Street, extending the Second Avenue Subway northward through midtown Manhattan to East 126th Street, the interface with Route 132-B. The latter continues the route northward through a tunnel under the Harlem River and thence easterly to connections in the Borough of the Bronx. The flexing connections with Route 131-A at East 63rd Street will provide service easterly to Queens.
Exhibit 2, Key Plan, focuses on Route 132-C and indicates its location within the existing street pattern and the general location of planned stations. Details of these stations are presented in Chapter III.
For Route 132-C, the Second Avenue and Water Street Subway, it is recommended that the Transit Authority adopt the plan depicted in Figures 1 through 6, the salient features of which are:
Whitehall Station, two mezzanines over two-level island platforms, four tracks, the south mezzanine connecting to the existing Whitehall Station on the BMT line, the north in the vicinity of Coenties Slip;
Pine-Wall Station, a continuous mezzanine from Wall Street to John Street, with single island platforms on two levels, four tracks, with mezzanine passageway entrance to Fulton Street for the South Street Seaport Museum;
Chatham Square Station, single mezzanine centered on Chatham Square with entrances to all sides of the Park Row-East Broadway-St. James Place-Oliver Street intersection compatible with traffic and pedestrian movements there;
Grand Street Station, improvement of the existing mezzanine and widening of the existing platforms to accommodate across-the-platform passenger transfer movements between the Second Avenue line, the Manhattan Bridge and West End services;
East Houston Station (existing Second Avenue Station) intersection, through the existing mezzanine, by two tangent, side platforms for the Second Avenue line;
14th Street Station, with interconnected mezzanines adjacent to the north and south of East 14th Street, with internal passageway connections to the side platforms of the existing Third Avenue Station on the 14th Street Canarsie line. This station has three tracks and two island platforms;
A pit track, between the two main line tracks, from East 16th Street to East 21st Street; and
23rd Street Station, with two mezzanines, one at East 23rd Street and the other at East 27th Street, and two tracks with an island platform.
Technical planning is the art of choosing among alternatives. Each of the alternatives must be thoroughly documented if it is to be understood and apportioned its rightful character and the magnitude of its attributes. With these in hand, judgments must be made through the weighing of these attributes as they conflict, qualify or eliminate in comparison with others. Lower Manhattan is an amalgam of history and comprises an accumulation of nearly three centuries of man's efforts to adapt the land to his uses. Each year the choices for those who would build new things become narrower as space, above and below ground, is filled rapidly with facilities and equipments deemed permanent upon completion.
It is of pertinence, then, to set forth the complex and difficult procedure through which the current vertical and horizontal alignment of Route 132-C of the Second Avenue Subway evolved. It can answer questions before they are asked, explain arrangements within their full context, and provide a view of the whole necessary for rational examination of the parts. There follows, therefore, a technical narrative of the development of the final concept.
The very first problem presented proved one of the most difficult: design of the terminal station at Whitehall and Water Streets. This station must do more than handle its passengers: it must not only contain facilities for the storage of trains during off-peak periods but turn back more than 30 trains per hour during rush hours. Failure of this station to perform this critical function comfortably could reduce capacity of the whole subway along its entire length. Yet both Whitehall Street and Broad Street already contain subway tracks and stations restricting the options for the new line.
Four tracks separated by two platforms requires a structural width of 100 feet. But Water Street between Whitehall and Broad Streets is not only less than 100 feet wide but is curved. This station arrangement, therefore, would require excavating under several of the many large new office buildings fronting Water Street including the plaza and shopping arcade of 1 New York Plaza, a difficult and costly procedure. But two tracks, astride a 24-foot platform, could be accommodated easily within the present street width, and four tracks provided by placing the pairs one above the other, and this is the solution adopted. This dual-level arrangement has the added advantage of permitting each of the "Bronx" and "Queens" trains to be reversed at different levels. Only half of the trains would operate over any one of the crossovers as they enter and leave Whitehall Station and crossovers on both levels will provide ample flexibility of operation to permit the reversing of even more than the scheduled 30 trains/hour at peak hours should the demand be made. This determination having been made, the next problem was the question of the vertical locaLion of the station.
The existing BMT station on Whitehall Street occupies the desirable depth for a new Second Avenue terminal station, as does the BMT stub trackage under Broad Street. It is impractical, therefore, to place the new subway n the same horizontal level as these existing structures and the Second Avenue line is forced, therefore, deeper in order to pass under them. Allowing for required double-level station height, the new station was placed at Elevation 5, or about 100 feet below ground level. This is a practical arrangement accommodating all significant local conditions. However, another consideration intruded.
Proceeding north, two obstacles intervene: the IRT Seventh Avenue ("2" and "3" services) Subway along Old Slip and the Eighth Avenue ("A" and "E" services) Subway on Fulton Street, both at approximately the same elevation. It is not difficult to pass under the first of these proceeding north but to pass over the IND Subway at Fulton Street demands a rapid climb, at a grade in excess of four percent from Whitehall Street. This is an excessive grade for routine subway operations, requiring major additional expenditure of power and braking costs and unacceptably slow acceleration from the departing station with a full passenger load. Modern engineering practice considers that a three percent grade is the maximum practical operating incline for steel wheel on steel rail rapid transit, if excessive power cost, equipment wear and reductions in schedule times are to be avoided.
Passage under the IND Subway posed problems for the planned Pine-Wall Station, lying between the Whitehall Station and the IND Subway at Fulton Street. Avoiding the excessive grade meant that the Pine-Wall Station must be placed deeper than otherwise planned. The final form of the station is shown as Section 3 in Figure 1, and will be seen that the two levels of double track serve center platforms which, in turn, are served by the continuous mezzanine only a few feet from the street surface. The provision of two platform levels in the Pine-Wall Station will minimize the effect of dwell time (i.e., loading time) in this very heavily-used station.
Prior to accepting this solution to the problems posed, a study was made of an entirely different approach using a "high" or minimum-depth subway from Whitehall Street northward. A study was made of a potential line at the 20-foot level under the street, the entire line to be installed using the cut-and-cover construction method. This alignment would require the removal of the stub tracks under Broad Street, which would shorten the "J" service by two stations, an unacceptable feature from a service and operations standpoint.
Continuing northward, the route from Pine-Wall Station transitions from two tracks over two tracks to two main line tracks on a single level in the vicinity of Fulton Street and climbs at required grade to the Chatham Square Station. Northward the route encounters the BMT Route 20 on Canal Street and the existing old Route 9 structure south of Canal Street, both of which are passed under without difficulty. Vertical alignment is controlled at the Grand Street Station by the existing platform level in that station for IND Chrystie Street Subway ("B" and "D" lines) and by the "B" and "D" line feeder tracks north of Canal Street. The BMT Center Street Loop on Delancey Street ("M" and "J" services) are surmounted without alignment difficulty. But this alignment along Chrystie Street encounters an environmental problem:
The amount of parkland required for temporary construction easement varies, the maximum width of encroachment being 40 feet at Rivington Street. Approximately 36,000 square feet of park will be required for construction. This is less than ten per cent of the total area of the park, which is a long, narrow strip, approximately seven acres in size, divided into three separate areas by Grand Street and Delancey Street, major east-west crossroads.
The park is presently in a very poor physical condition and is only lightly used. Access to it is limited because of grade differential along the Chrystie Street side. The park is mainly used by local residents for sitting and for strolling along the walkways parallel to Chrystie and Allen Streets. The existing active recreational facilities (basketball courts and playgrounds) are little used.
Referring to Figure 13, the park presently contains four buildings which from south to north may be described as follows: a two-story brick building, the first floor of which is used by the Parks Department while the second floor is completely vandalized and vacant; next a comfort station brick building which is completely vandalized and not in use; next, the Sara Delano Roosevelt Golden Age Center, a one-story brick building, relatively new and in good shape, and in active use, which will be underpinned and maintained in use during construction, and finally a one-story brick building in good repair being well used as a community center. After completion of the subway construction in the park, the part of the park affected will be rebuilt, restored to its original condition, and refurbished. Approximately 97 trees in the park will be affected by the construction. These are mostly London Plane trees with some trees of the Ginkgo variety. Maximum trunk size of the Plane trees, measured four feet above the ground, is 20 inches in diameter, while the Ginkgo trees have a trunk size of three to six inches. Due to the limited ground cover above the subway, even with tunneling, about half these trees affected by open cut would have to be transplanted. A consulting arborist has been retained on the project to advise on care of the trees and transplanting methods to be followed.
All proposed construction work will have to be approved by the Administrator of Parks, Recreation and Cultural Affairs Administration, City of New York. Except for temporary diminution of the area of the park available, construction of the proposed Route will not interfere with any of the regular activities of the park users.
We understand that it is the intention of the Transit Authority to engage a consulting park architect for the purpose of drafting a master plan for restoration and ultimate development of Sara D. Roosevelt Park. Services performed by this consultant would include (but not be limited to) preparation of a detailed development program showing construction staging and utilization of the recreational areas in addition to providing general input for the restoration of the park with sufficiently detailed information to permit a future architect to prepare contract drawings and specifications.
A close coordination of efforts will be necessary between all interested parties and agencies having jurisdiction of the park area in order for this segment of the project to be successfully realized.
To meet the level of the existing platforms in the Grand Street Station, and due to other existing restraints between approximately Canal Street and East Houston Street, the profile of Route 132-C on Chrystie Street will necessarily be shallow. The alternative of tunneling under the Sara D. Roosevelt Park was investigated, with the additional cost of tunneling construction estimated to be $10 million.
Northward the subway passes through the East Houston Street Station and thence to the 14th Street Station. It is desired to have a separate pit track in the vicinity of the 14th Street Station for the inspection and light maintenance of subway cars in operation on the Second Avenue line, and this pit track on the "high line" study was located between East 8th Street and East 12th Street. Adjacent to the pit track facilities would be the necessary crew quarters and parts and tool storage rooms.
The work of the "high line" study was continued northward until it encountered difficulties at the 14th Street Station presented by the existing Canarsie line on East 14th Street. The Canarsie line is shallow so that it is necessary for the new Second Avenue Subway to pass under this existing subway. Here the geology of the site comes strongly into play. Generally, rock tunneling is less expensive than cut-and-cover construction and, therefore, to be chosen when all other factors are compatible. It is in the vicinity of this station that the rock line rises to within 30 feet of the ground surface. The Canarsie subway structure lies above the rock.
In order to use rock tunneling construction, the profile must be dropped sufficiently below the existing structure to provide the minimum necessary rock cover above the crown of the tunnel. For this reason, the Second Avenue Subway line is dropped in this area to a depth of about 80 feet below the surface. This solution has an effect on the location of the inspection pit previously mentioned.
This 615-foot-long pit track section must be level to permit de-energized parked trains to remain stationary; a grade in such area could generate unwanted train movement with attendant risks. The deeper tunnel proposed for the 14th Street Station rendered the provision of a 615-foot stretch of level track between East 8th and East 12th Streets virtually impossible. Therefore, this inspection pit section was relocated north of the 14th Street Station where it is possible to provide a level 615-foot-long section. A third track through the 14th Street Station facilitates access to and from the pit track section.
The balance of the line from 14th Street Station to Kips Bay Station at the interface with Route 132-A was explored as a continuation of the "high line" but the rock line proved determinant in this region, and to preserve required cover of solid rock, the final elevation chosen was below the alternatives studied and the subway enters the Kips Bay Station some 60 feet below the surface where it meets the profile previously established for Route 132-A. This clears by an adequate margin the Penn Central rail tunnels some 20 feet deeper.
The RECOMMENDED SCHEME was evolved from improvements to both Schemes I and II. In profile, at the south end, it envisages two-level platforms at both Whitehall Station and Pine-Wall Station, as required for passenger traffic and train operating purposes. The platforms of Whitehall Station would be constructed deep in rock so as to avoid disturbance to the existing transit tunnels on Whitehall Street and Broad Street including stub tracks there. The track grades are limited to 3.0 percent. In this area as much construction as is practical would be by rock tunnel, up to approximately Pine Street, where rock dips down sharply to the north. It was concluded that Route 132-C must pass under the existing Fulton Street transit tunnels. To the north of Fulton Street, the profile of Route 132-C rises steadily, mostly at 3.0 percent grade, to the Chatham Square Station. From Chatham Square the profile is similar to Schemesl and II, being constrained by existing and possible future transit tunnels under the Manhattan Bridge Plaza and the necessity to meet fixed elevations in the existing Grand Street and East Houston Street Stations. Proposed scheme for Sara D. Roosevelt Park is shown in Figure 13.
North of East Houston Street Station, the profile of Route 132-A drops at 2.9 percent reaching rock at about East 7th Street. The profile from this point to the north has been set deeper than Scheme I, in order to maximize the amount of construction that would be in rock tunnel. Station mezzanines will be constructed by cut-and-cover methods in any event. Tunneling is planned where the platforms of the 14th Street Station are under the Canarsie line structure in order to minimize disturbance to, and construction problems under, that structure. Advantage is taken of the rock cover up to approximately East 32nd Street, where the rock level again dips down, necessitating a short section of cut-and-cover construction adjacent to the interface with Route 132-A, just south of the Kips Bay Station for which cut-and- cover construction was planned. It is noted that the profile at the extreme south end of Route 132-C, RECOMMENDED SCHEME, is such as to not preclude future extensions to the south, to Staten Island or to Brooklyn. The RECOMMENDED SCHEME has entirely acceptable track grades, includes all the operating features requested by the Transit Authority, and will utilize tunnel construction to the maximum degree practical to minimize the impact on surface conditions during construction.
Length of cut-and-cover 12,400 feet Length of tunnel 6,700 feet Estimated Construction Cost (including Utility Relocation) $327,000,000 Estimated Annual Operating and Maintenance Costs $1,230,000* *Expressed in mid-1973 dollars.
The subsurface at the south end of the Second Avenue and Water Street Subway, Route 132-C, from approximately Whitehall Street to Pine Street, consists of fill, overlying dense, saturated sand, overlying rock. The rock is relatively shallow, from 30 to 40 feet below the street surface. In the vicinity of Pine Street, the rock dips down sharply to the north, being approximately 140 feet below ground level at Fulton Street, 175 feet below ground level north of the Brooklyn Bridge, and remains deep to about East 6th Street. The subsurface consists of fill overlying large horizontal lenses of organic silt near the ground water level, and below it consists of overlying medium to dense saturated sands and sandy silts. North of Chatham Square, the fill overlays dense sands and sandy silts, above the water table, and north of Canal Street, the subsoil consists of dry dense sands and sandy clays, these comprising the rock overburden to the north end of Route 132-C at East 34th Street. Rock occurs approximately 150 feet below ground level at East Houston Street and rises to the north to approximately 25 feet below ground level at St. Marks Street. Continuing north, the depth of rock is quite variable from approximately 15 feet to 45 feet below ground level, with dips at East 20th Street and East 32nd Street.
During the course of the study, information on the principal existing underground utility installations was obtained from the owning public utilities, agencies or companies. These materials indicated that the major utilities, all lying fairly close to the surface, would not constitute a determinant in the alignment of the subway. However, their preservation in continuous use was planned and associated costs for service maintenance and, in some cases, relocation in the cut-and-cover sections, were estimated.
The Steam Division of the Consolidated Edison Company has pipes deployed throughout the area of the route. These vary in size from 8 to 24 inches in diameter for the pipe itself, but the addition of thermal insulation and protection against mechanical damage increases their diameter another 12 inches. The system contains such auxiliary apparatus as anchor and thrust blocks, expansion joints, coolers and blow-offs. The following major lines parallel the proposed route: along Water Street from Broad Street to Fulton Street; along Pearl Street and St. James Place from Beekman Street to Madison Street and along Second Avenue from 13th to 15th Street, from 17th to Zoth Street and from 22nd to 23rd Street. Lateral lines cross the route at Broad Street, Old Slip, two lines at Wall Street, and lines at Fulton Street, 15th Street and 20th Street.
Cables in Empire City Subway Co. ducts will consume major restoration costs and represent a major item in the time scheduling. Their number and need for maintenance in use comprise a design and construction factor. These are low voltage lines used for the transmission of various types of communications, such as audio-visual, electro-mechanical control and the transmission of computer input data. The number of ducts lying parallel to the alignment varies greatly. Along Chrystie Street there is a main bank of 80 ducts, and on Water Street a main bank of 120 at the center with a lesser bank of 24 to the east. Crossing the route are many banks influenced by the location of central telephone offices. The Telephone Company is contemplating a major increase in plant, including 200 ducts from north of 23rd Street to the new building north of Brooklyn Bridge and continuing south.
Some of the existing cable may be moved, within the limits of their existing slack, but the highly sophisticated T-l control lines can not be readily shifted as any change in their physical alignment affects their electrical characteristics. These installations will be costly and time-taking to handle.
Manhole locations serving T-1 Carrier Apparatus Cases are at:
The route is interlaced with duct lines and cables of the Consolidated Edison Company including transformer vaults and access manholes. There are three "Oilastatic" lines, one feeding the new World Trade Center and two on 23rd Street that cross Second Avenue. These lines vary from dual five-inch lines to two 10-3/4-inch pipes plus two six-inch oil lines. Additional to these major lines is the variety of Transit Authority power and communications lines in the vicinity of existing subways and stations. Virtually all of these will remain undisturbed in continuous service.
Normal pressure water pipes in the area are generally 12-inch in diameter but major high-pressure lines exist, including three long runs of 20-inch diameter pipe and one 36-inch line, all in the vicinity of the proposed alignment but well above it.
Rock tunneling will be conducted well below existing sewer lines but cut-and-cover work will require temporary interruption and some permanent relocation of sewer lines. This will be the case at the 14th Street Station, which will have connections to the west requiring realignment of sewers in the area.
The route contains a wide variety of gas lines, varying from six to twelve inches in diameter and arranged in multiple and parallel installations. These latter contain cross-connections to equalize pressures. These are generally low-pressure cast iron pipes. However, there is a 24-inch medium-pressure line from East Houston Street to 32nd Street. None of these intrude into the proposed alignment at its planned elevation.
Pursuant to our Agreement with the Transit Authority, we have prepared comparative annual operating and maintenance costs for the three basic schemes developed for the Second Avenue line, Route 132-C. Included were an analysis of the annual hours of operation, computation of the electric energy used, and its annual cost, and estimates of annual cost of maintenance, supplies and parts for the particular unit. These analyses cover the annual operating and maintenance for the following sub-systems:
The operating and maintenance costs do not include the cost of electric power for traction, signals, communications or lighting nor the cost of maintenance of substations, track, signals, communications, lighting, cars or station cleaning.
Taking all of the foregoing into account, the following is a summary of annual operating and maintenance costs:
Operating Maintenance Total Scheme Cost Cost Annual Cost I $715,000 $405,000 $1,120,000 II $670,000 $400,000 $1,070,000 Recommended $795,000 $435,000 $1,230,000
The RECOMMENDED PLAN is the most costly from the standpoint of operating and maintenance cost, because it has the deepest profile.
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