RANSPORTATION LIBRARY T-G Z5f h N li:Tr ~;.`~~ rl~-F.,.-~.b:~~~.lS::CJCi r.~~.C S...b'. "F;STf'i Y -: It-'~ ~ L i i `(ji ~;;"~*?f'~''"`,I r ~\ ~e ~t. ,:*?.....-;t~~i ~~.i~. ':"! ~~:."' "'' c '' * -~ r. lr'?y: "' ~..1 . ::::. ~:R. I,I ~r ~ ~~ i. r:~~ 7 ~rJr. ~~1 1 5;,~~i ~~~,. ~ * '~ rU.-' ~~ ~I '~~~~ C 420,702 I If vl jrz.r~;_~ -;~;rF; ~' i..L.:~~S '`~:~~ F'::~~~~.~e;:~~ Ih ~r' r. i'; ~5 ~";. * r ~ A. - - ~~ -—: THE PORT OF NEW YORK AUTHORITY -CREATED BY COMPACT BETWEEN THE STATES OF NEW YORK AND NEW JERSEY AND RATIFIED BY CONGRESS TENTATIVE REPORT OF BRIDGE ENGINEER ON HUDSON RIVER BRIDGE AT NEW YORK BETWEEN FORT WASHINGTON AND FORT LEE =A FEBRUARY 25, 1926 PROPER"I Or t a A RT ES SC I E N'I A VERITAS :..t. I; "j 11.. 1a T THE PORT OF NEW YORK AUTHORITY CREATED BY COMPACT BETWEEN THE STATES OF NEW YORK AND NEW JERSEY AND RATIFIED BY CONGRESS TENTATIVE REPORT OF BRIDGE ENGINEER ON HUDSON RIVER BRIDGE AT NEW YORK BETWEEN FORT WASHINGTON AND FORT LEE FEBRUARY 25, 1926 NEW YORK, N. Y. PANDICK PRESS, INC., PRINTERS 1926 -~2i -Ii S~0 THE PORT OF NEW YORK AUTHORITY Commissioners JULIAN A. GREGORY, Chairman FRANK C. FERGUSON SCHUYLER N. RICE JOHN F. GALVIN, Vice-Chairman OTTO B. SHULHOF HERBERT K. TWITCHELL J. E. RAMSEY, Chief Executive Officer JULIUS HENRY COHEN, Counsel WILLIAM LEARY, Treasurer WILSON J. VANCE, Secretary ADVISORY COMMITTEES ON HUDSON RIVER BRIDGE New York GEORGE GORDON BATTLE ALBERT S. BARD MRS. JOHN KIRKLAND CLARK FREDERICK S. GREENE JOHN M. HAFFEN CHARLES HARWOOD SULLIVAN W. JONES E. VD. H. KOCH GEORGE F. KUNZ BENJAMIN W. MORRIS ROBERT MOSES EDWARD C. PALMENBERG GEORGE W. PERKINS HENRY W. SACKETT J. CONRAD SCHEIDER MISS LAURA A. SKINNER New Jersey C, V. R. BOGERT MRS. EVERETT CARTER WILLIAM CONKLIN JOHN G. EDSALL EARNEST J. HEPPENHEIMER MRS. MABEL S. LORD DUNCAN McCLAVE MRS. DWIGHT W. MORROW DAN FELLOWS PLATT ERNEST A. SIBLEY MRS. E. E. VANN JAMES WILSON I THE PORT OF NEW YORK AUTHORITY 11 BROADWAY NEW YORK March 11, 1926. To the Governor of the State of New York: To the Governor of the State of New Jersey: SIRS:-We herewith transmit to you the Tentative Report of our Bridge Engineer dealing with a bridge across the Hudson River between Fort Washington and Fort Lee, which gives the engineers' tentative conclusions. We send this report at this time in order that you may have the latest available engineering information on this matter. The Commission has not yet determined the design or location of the bridge. We have the honor to remain, Respectfully, JULIAN A. GREGORY, Chairman, JOHN F. GALVIN, Vice-Chairman, The Port of FRANK C. FERGUSON, New York Authority OTTO B. SHULHOF, SCHUYLER N. RICE, HERBERT K. TWITCHELL, Commissioners. P) —" I -- ---------- -— I- -— e l... --- —-r. bo '0 ' -4 -4. 0 -4-A ~0 U, 4-4 0 U, bo) 0 '-4 4-i 0 V-4 rc$ w 93 0 04 0I bI 4 -k..Ca 4.4 I' I I.- " *^ -1", i 1 -- ---— " —" *ra*~ara-' --- —-- i lr-~~eann~elr`~- - — l~- -L~.. THE PORT OF NEW YORK AUTHORITY TENTATIVE REPORT OF BRIDGE ENGINEER ON HUDSON RIVER BRIDGE Between Fort Washington and Fort Lee February 25, 1926. To the Commissioners of the Port of New York Authority: DEAR SIRs:-The preliminary work necessary for the planning and construction of the Hudson River Bridge between Fort Washington and Fort Lee, with which The Port of New York Authority has been charged by the Legislatures of New York and New Jersey, has now advanced to a point where conclusions can be drawn regarding the physical and financial feasibility of this bridge, its necessity as a link in the local and interstate transportation systems, its location, size, type, method of construction, approximate cost and aesthetic merits. Briefly the work so far accomplished embraces comprehensive traffic studies to determine the probable volume of traffic over the bridge and the revenues to be derived therefrom, topographical surveys, river borings and engineering design studies to determine the suitable site, size and type of crossing and its cost, and finally, architectural studies to determine the feasibility of rendering the bridge a befitting object in a charming landscape. The project being of exceptional magnitude and complex aspect, it was necessary that the preliminary studies be undertaken with great care and thoroughness. The appropriations by the two States for these preliminary studies, amounting to $200,000, became available only on July 1, 1925, and the time has not been sufficient to permit either the completion of the studies or the rendering of a comprehensive report on the project. However, it is believed that from the studies so far completed the following conservative conclusions may be drawn: CONCLUSIONS (1) The traffic studies reveal an urgent demand for a crossing for vehicular traffic in the vicinity of the proposed bridge to relieve the present intolerable traffic situation. The traffic volume is of more than sufficient magnitude to make it financially feasible to construct, operate and maintain, from tolls, such a crossing, not considering the broader benefits to the people of both States as well as to the local community. [1] 2 THE PORT OF NEW YORK AUTHORITY (2) The general location of the bridge is well chosen with regard to topography in its vicinity and the feasibility of convenient connections to the important local and arterial highway routes on both sides of the river. A crossing at this point also appears to be the next logical step after construction of the vehicular tunnel at Canal Street, since the two crossings are far enough apart not to influence materially each other's traffic quota. (3) From the engineering point of view the construction of the bridge is in every respect feasible and, while of unusual magnitude, will involve no extraordinary difficulties, nor hazardous or untried operations. The bridge will have a single river span of at least 3500 feet and a clear height above water of about 200 feet. The piers will be located within pierhead lines, as established by the War Department, and will therefore be no obstruction to navigation. (4) The bridge is to be of the suspension type, the most economical and aesthetically superior type available. It will be of extremely simple construction, and its design is conceived so that it will be feasible to build the bridge at a minimum initial expenditure to serve present traffic needs, and to enlarge its capacity as the traffic volume increases. (5) If funds for construction of the bridge shall become available in 1927, it is expected that not later than 1933 the bridge will be open for four-lane vehicular and bus passenger traffic and for pedestrians. It is estimated that this capacity will suffice to take care of the initial traffic and the expected increase until about 1943, whlen it will probably become necessary to enlarge to an eight-lane vehicular capacity. (6) While it is not possible, at the present time, to report definite cost figures, it is estimated, upon information so far available and upon such forecast of real estate values as may now reasonably be made, that the bridge can be opened for highway traffic at a cost of less than $50,000,000, inclusive of interest during construction. (7) Depending upon the traffic capacity finally to be decided upon, it is estimated that the bridge can later be enlarged at an additional cost of between $15,000,000 and $25,000,000, if, and when, the vehicular and passenger traffic will have grown in volume to pay for this additional cost. (8) On the basis of conservative traffic analysis, and without counting upon the vehicular traffic which will be generated by the construction of the bridge, nor upon possible income from other than vehicular traffic, it is estimated that during the first year after completion the revenue will TENTATIVE REPORT ON HUDSON RIVER BRIDGE 3 more than cover the annual interest charge, administration, maintenance, and amortization. The bridge will thus be self-sustaining in every respect from the first year without imposing unreasonable toll charges upon the traffic. (9) On the basis of conservative assumptions for future growth of traffic, and counting upon revenue from vehicular traffic alone, it is estimated that within ten years after opening to traffic the bridge may be enlarged to eight-lane capacity, and that within twenty years thereafter the entire bond issue raised to cover construction cost can be amortized. (10) The architectural studies so far made, while yet tentative, indicate clearly that the bridge may be so designed as to form an object of grace and beauty as well as utility, and to blend harmoniously with the grandeur of its natural setting. (11) In view of this favorable aspect of the bridge, its urgent necessity to relieve traffic conditions and in order to derive the benefit of a complete investigation, it is recommended that the preliminary work be carried to completion, and that the States be asked to appropriate an additional sum of $100,000 to make that completion possible. Following is a more complete and detailed account of the work so far accomplished: TRAFFIC STUDIES Since the Legislative Acts provide that the Port Authority may levy charges for the use of the bridge and that the bridge shall be built and paid for in whole or in part by bonds of the Port Authority, or other securities, it has been necessary to ascertain whether or not the revenues from tolls for vehicles and pedestrians, and possibly franchise rights for rail passenger facilities, will be adequate to meet the cost of construction. This involves the study of a number of traffic factors, viz.: First: The present volume of vehicular and pedestrian traffic over each of the seventeen ferries across the Hudson River. Second: The volume of traffic the bridge will be expected to attract when it is opened to traffic. This requires an estimate of the effect on the bridge traffic of the opening of the vehicular tunnel in 1926. Third: The volume of traffic that can reasonably be expected to be diverted to the bridge from each of the other crossings in that year. Fourth: The volume of traffic over the bridge for each year, for twenty years subsequent to the opening of the bridge, proper allowance 4 THE PORT OF NEW YORK AUTHORITY being made for the effect upon the bridge traffic of the possible construction of other crossings below 179th Street, Manhattan. This necessitates the determination of the origin and destination of vehicles by types for the existing ferries and apportioning the divertible traffic to each of the proposed crossings in such a way as to take into account relative distances and ferry, tunnel, and bridge charges and the elimination of undue congestion on the approach streets to each of the proposed facilities. Fifth: An estimate of the revenues for each year subsequent to the opening of the bridge, based upon an average toll per vehicle and per pedestrian. In order to estimate the vehicular traffic, it was necessary to obtain the trend or rate of growth of the present day traffic over seventeen ferries between the Battery and Tarrytown (for the most recent normal year). This required the records, by classes of vehicles, kept by each of the ferry companies from 1914 to date. Where revenues only are available for this traffic, average tolls for each class of vehicle must be applied to the revenues to estimate the number of vehicles. From these records the volume of traffic over each of the ferries can be forecast for each of the years subsequent to 1932. Instead of forecasting the traffic for each of the ferries it is better to forecast the volume of traffic that will be diverted from the existing ferries to the bridge. To obtain this divertible bridge traffic it is necessary first to ascertain the distribution of the present-day traffic over each of the ferries for the most recent normal year. To do this the origin and destination of each vehicle is necessary for a sample period of time, so selected that the peak and the average traffic condition in the year will be reflected. These occur in the months of July and October. The variations of traffic between week-days and Sundays and from hour to hour, or both, are necessary to estimate the peak traffic conditions to test out the roadway capacities on the bridge. Field clockings, therefore, were taken by placing inspectors on each of the ferry boats of every route to ride the boats throughout the day. The inspectors ascertained and recorded the following information respecting each vehicle crossing the river by ferry: (a) Type of vehicle, that is, whether horse drawn or motor propelled. A division of motor vehicles was made as between commercial and pleasure, and again sub-divided to indicate the carrying capacity of the commercial vehicles and the seating capacity of the pleasure vehicles: (b) Number of persons carried in each vehicle; TENTATIVE REPORT ON HUDSON RIVER BRIDGE 5 (c) State license; (d) Origin and destination of each vehicle; (e) Frequency of use of ferry route by each vehicle. These clockings were made throughout the months of July, August, September and October, 1925. In carrying forward the clockings a field force of fifty-six men was employed on the seventeen ferry routes. The detailed information noted above was ascertained and recorded for a total of 242,000 vehicles. Clockings were made of the vehicular traffic now passing over the streets and street intersections in the vicinity of the proposed location of the bridge, to determine the degree to which capacity of these streets is now used. Also a study was made to determine the volume of traffic carried at present by the East River bridges, particularly during the peak of travel; and the extent of saturation. Examination of the records of the various ferry companies operating the seventeen ferry routes, for the purpose of ascertaining the volume of traffic and its classification handled by the ferries of each route for the past ten years, has required a force of three to four men constantly from July to the present date. After having completed the field clockings, the next step was the tabulation and summarization of the data. The work of tabulating was carried on in part during the period of clocking and has proceeded since the clockings were completed in October, to bring it to a point to permit of detailed analysis. These analyses are for the purpose of determining future distribution of vehicular traffic among the present crossings, the proposed 178th Street bridge, and any other crossings that might later be constructed and which might affect the future revenues of the 178th Street bridge. One of the first determinations to be arrived at by analysis is the probable volume of traffic that may be expected to use the 178th Street bridge when it is opened, assuming that were the only highway across the Hudson River between Manhattan and New Jersey. The second determination to be made is the volume of traffic which will be attracted to the vehicular tunnel, when it is opened, which otherwise might, in part at least, have used the 178th Street bridge. The third determination is the probable effect on the 178th Street bridge traffic by the opening of any additional highway crossings over the Hudson in the future. Each of these steps involves a large number of intermediate steps. For example: highway access to the bridge; determination of a toll which will - I I FIRST TENTATIVE ESTIMATE OF TOTAL HUDSON RIVER TRAFFIC AND AMOUNT DIVERTED TO THE PROPOSED HUDSON RIVER BRIDGE LUL z 0 c() Q D I LUI I r r H z (I) 0 LU Q) LU IL 0 r LU D z _ Tl 4000000 30000000 25 00000- HUDSON RIVER FERRY AND TUNNEL TRAFFIC ooooooo 15ooooo i II i0oooooo ) I I I I I I HUDSON RIVER BRIDGE TRAFFIC I I T1945 | | 9 I O 0. I I. I * I I I I I I I I I I I - I I I I I II 19151 I I I 119201 1 I 1 119251 1 I 11931 I 1935 I I 19551 I I I 9i I I I ~I ~ I I I I I - I I I ~ I I I I L_ F Jl1 I I I I - -I... -.-.. -.- I I - I I I Y- - - I Exhibit (A) Estimate of Hudson River Bridge Traffic TENTATIVE REPORT ON HUDSON RIVER BRIDGE 7 secure maximum traffic and maximum revenue; future crossings to be constructed by the City of New York across the East and Harlem Rivers; and traffic that will be generated by the stimulation of industrial and residential development, particularly on the Jersey side. The results of-all of these traffic studies are now being carefully recorded and will be included in a later report on the project. Exhibit (A) illustrates the growth of the total trans-Hudson vehicular traffic as tentatively estimated, fom 1924 to 1960, inclusive, and the number of vehicles of this total traffic which would have been, or will be, diverted to the 178th Street bridge. Below is recorded the first tentative estimate of total trans-Hudson vehicular traffic for all ferries from the Battery to and including Tarrywill divert from these ferries and the town, and the traffic that tunnel. the bridge Year 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 Hudson River Traffic 11,706,000 12,912,000 14,185,000 15,510,000 16,887,000 18,313,000 19,815,000 21,284,000 22,740,000 24,193,000 25,607,000 26,984,000 28,280,000 29,484,000 30,607,000 31,678,000 32,689,000 33,619,000 34,484,000 Bridge Traffic 3,208,000 3,596,000 4,017,000 4,459,000 4,921,000 5,406,000 5,903,000 6,404,000 6,904,000 7,401,000 7,889,000 8,364,000 8,807,000 9,221,000 9,609,000 9,971,000 10,321,000 10,642,000 10,937,000 Year 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 Hudson River Traffic 35,298,000 36,055,000 36,767,000 37,408,000 38,006,000 38,579,000 39,105,000 39,589,000 40,045,000 40,465,000 40,841,000 41,172,000 41,478,000 41,765,000 42,032,000 42,282,000 42,532,000 42,766,000 Bridge Traffic 11,216,000 11,476,000 11,723,000 11,944,000 12,153,000 12,355,000 12,538,000 12,708,000 12,868,000 13,016,000 13,144,000 13,263,000 13,369,000 13,471,000 13,565,000 13,651,000 13,738,000 13,821,000 These figures must be revised as the analysis proceeds to take into account the effect of the opening of additional crossings. The above figures do not include traffic which will be generated from the adjacent territories, whose growth the bridge will stimulate. While this cannot be measured accurately, an analysis of the growth of population, intensity of realty development, and motor vehicle registration is in process to determine the effect of the East River bridges upon Brooklyn and Queens, in order to gauge roughly the effect that the Hudson River bridge will have upon -— I_ I u 0 C1\3 R I/ r R Zr R THE POTOF NE W YORK A U THORI TY HUDSON RIlVE BRIDGE FORT WASHINGTON - ORT LEE HMP J5nowcwGALrTCNAT LOCAT ON Exhibit (B) Location Map TENTATIVE REPORT ON HUDSON RIVER BRIDGE 9 Fort Lee and its contiguous communities. The amount of this traffic will be considerable and eventually will be added to the above estimates. While the above traffic is the principal source of revenue, there are four other sources which will contribute to the income of the bridge. This revenue will come from passengers in vehicles, pedestrians, bus lines and rapid transit facilities. Studies are under way to ascertain the potential traffic which will give rise to this income and will be presented in a later report. Tables (1-a), (1-b), (1-c), appended to this report, give the gross revenues estimated to date for a 50~ rate, a 600 rate, a 700 rate, respectively, from vehicles only. It will be seen that for 1933, or the first year of operation, the income from vehicles alone is forecast as at least $3,700,000. Subtracting the charges for administration, maintenance and operation, the net operating income is close to 6~/2% on the $50,000,000, the probable maximum initial cost of the bridge. In addition, there will be revenue from passengers in vehicles, pedestrians, and bus lines, and from vehicular traffic which will be generated by the bridge. Consequently, it is safe to conclude at this time that the charges on the initial and ultimate cost of construction can be met out of the potential revenue from traffic, and that therefore the project is economically sound. LOCATION STUDIES The Legislative Acts of New York and New Jersey provide that the bridge shall be located at a point between 170th and 185th Streets in Manhattan, New York City, and a point approximately opposite thereto in the borough of Fort Lee, New Jersey. After a general examination of the territory on both sides of the river, within these limits, three specific sites which appeared to offer possibilities were tentatively selected for more careful study. (See location map, Exhibit B.) The three sites chosen are those in close vicinity of 181st Street, 179th Street, and 175th Street, Manhattan, respectively. River borings, studies of approaches, grades, street connections, tentative designs and comparative cost estimates were made for these locations. These studies revealed the central location near 179th Street as being not only the most economical, but also the most desirable with respect to approach grades and street connections and natural setting, and it was therefore decided to confine the elaboration of more complete plans and estimates to this location. In the selection of the locations, careful consideration was also given to the scenic effect of the bridge, more particularly with regard to the ef 10 THE PORT OF NEW YORK AUTHORITY feet upon Fort Washington Park. While, by locating the bridge at 181st Street or 175th Street, encroachment upon this park by bridge piers might be avoided, the much longer river span required at these locations, and the consequent greater proportions of the bridge, would not be as favorable, aesthetically, as a bridge at 179th Street. Moreover, the location of a pier in the Park is not believed to curtail in any way the usefulness of the Park or to mar its beauty. TOPOGRAPHICAL SURVEYS, MAPPING AND TRIANGULATION Owing to lack of maps, sufficiently accurate and complete for preliminary planning and reliable estimates of cost, it has been necessary to undertake extensive and accurate topographical surveys extending over the territories on which the bridge approaches and street connections may be located. These surveys are now nearing completion and will form a valuable basis for the final planning and construction of the bridge. The results of these surveys have been embodied in a large map to the scale of 1" — 100'. Owing to the lateness of the season it has been found impracticable to undertake an accurate triangulation across the river, but the necessary base lines have been established, and all other preparations for these measurements have been made, and it is expected that they can be accomplished in the Spring as soon as weather conditions permit. For the tentative studies, the triangulation made by the U. S. Coast and Geodetic Survey was considered to be sufficiently reliable. RIVER BORINGS In order to obtain reliable information on the character of the river bottom and to establish beyond question the surface of the solid bedrock upon which the bridge piers have to rest, it was necessary to undertake borings carried well into the solid rock. In all, sixteen borings, at the three locations tentatively selected, have been sunk, the results carefully recorded and the rock cores preserved. These borings have established the fact that, outside of the pierhead lines established by the War Department, that is, within the width of river reserved for navigation, bedrock is too deep to permit of economical construction of bridge piers and that such piers must, and can, be placed between the pierhead lines and the shore, or on shore. Moreover, thus located, the piers will form no obstructions to navigation. The borings were carried out under contract awarded to the Osborne Drilling Company in October and were completed in November, 1925. TENTATIVE REPORT ON HUDSON RIVER BRIDGE 11 Additional borings will have to be made when the location of the bridge is definitely established. The character of rock revealed by these borings corresponds to that prognosticated by the U. S. Geological Survey. On the New Jersey side bedrock was found to consist partly of solid red sandstone and shale, known as the "Newark Formation", partly of the so-called "Stockbridge Dolomite" which forms the major portion of the rockbed under the Hudson River. The borings on the New York side revealed a solid bed of "Hudson Shist" (mica shist), which is the prevailing rock of Manhattan Island. All of these rock formations are sufficiently hard to constitute a solid and permanent foundation for the bridge piers and to safely sustain the great pressure from them. The material overlying the rock is almost entirely river silt, unsuitable for foundation purposes. ENGINEERING DESIGN STUDIES In order to determine the most economical and suitable type and general proportions of the structure, for various possible locations, it was essential to undertake extended comparative design studies and cost estimates, before any final planning could be undertaken. Complete tentative designs were made for a 3500 foot river span and a 3900 foot span, as required for the 179th and 181st Street locations, respectively. Comparative estimates of cost have also been prepared for various capacities for highway traffic and for combined highway and rail passenger traffic. Various possible forms and materials for the individual parts of this structure were given most careful consideration, and all essential features of the structure have been studied in detail with a view to assure not only economy, but conformity to the most advianced standards of design and methods of fabrication and construction. Tentative schemes of erection have been evolved, inasmuch as the method of erection of a large bridge not only has an important bearing upon its design and economy, but because in this case it involves operations of unprecedented proportions. As a result of these studies a tentative design has been developed which, for the 179th Street location, may be briefly described as follows: TYPE AND GENERAL PROPORTIONS OF BRIDGE Little study was necessary to determine the suspension bridge as the most suitable type, because its superior economy for such great spans and capacities is now generally recognized by engineers. Its superior 12 THE PORT OF NEW YORK AUTHORITY aesthetic merits, when properly designed, further single it out as the best adapted type in this case. A cantilever bridge, the nearest other possibility, would, with its dense and massive network of steel members, form a monstrous structure and truly mar forever the beauty of the natural scenery. The general proportions of the bridge, as to length of spans and height above water, were sharply defined by the topographical and geological conditions of the site. As a result of the borings, heretofore described, the main pier on the New Jersey side was located well within the pierhead line at a point where rock can be reached at a depth of about 100 feet, which is the approximate limit for the pneumatic process, the safest and most reliable foundation method. On the New York side the logical and natural place for the pier is the rocky point of Fort Washington Park close to the pierhead line. This results in a central span of 3500 feet between centers of piers, or twice the span of the Philadelphia-Camden bridge, the longest suspension bridge so far built. The rock cliffs of the Palisades form the natural abutment and anchorage on the New Jersey side and, for the sake of symmetry, which is an essential aesthetic requirement, the side span on the New York side is made the same, or approximately 700 feet. The clear height of the bridge floor above water is approximately 200 feet, this height resulting from the elevations of the connecting streets on both sides of the river and the limiting grades of the approaches. Incidentally, this height is ample to permit passage of the largest vessels which are likely to go up the river beyond this point. The general form and arrangement of the structure are of extreme simplicity. Essentially the floor deck is suspended throughout its length from simple cables or chains. The latter will pass over the two towers and are to be firmly anchored in rock or massive concrete blocks at their ends. To enhance the gracefulness of the bridge, the cables are to have a comparatively small sag or flat catenary. Structurally, the cables are to be built either of steel wires or of high grade steel eyebars, both types of construction having reached a high degree of perfection in American bridge practice and a degree of safety superior to that of any other type of structural members. Detailed studies have been made of two essentially different types of towers, a slender steel tower, as exemplified in the Manhattan bridge, and a combined steel and masonry tower of massive appearance. While the economic merits of the slender steel tower, and its justification in some TENTATIVE REPORT ON HUDSON RIVER BRIDGE 13 localities, are recognized, it is felt that the conspicuous location of the proposed bridge in the midst of a bold and impressive landscape makes the selection of the aesthetically superior massive tower imperative. TRAFFIC CAPACITY OF BRIDGE One of the most important and complex questions which had to be solved, and will involve further careful study in connection with the planning of this bridge, is the determination of its traffic capacity, as regards both kinds and volume of traffic. The question is necessarily closely related to the study of the traffic situation and definite solution has to await the results of these studies. While the Legislative Acts do not specify the kind of traffic to be accommodated, existing conditions point clearly to the need of a crossing primarily for vehicular traffic. Furthermore, while the development of the territories contiguous to the bridge will, sooner or later, call for the accommodation of a considerable volume of passenger traffic, it is not likely that rapid transit or other rail passenger traffic facilities will be needed for many years to come. It is also realized that the demand for passenger traffic in the immediate future, and possibly for many years to come, may be filled by passenger buses running over the bridge roadway. Any provision for the accommodation of rail traffic, which would involve a comparatively large outlay at present, would therefore not be warranted. As a result of our studies it now appears quite feasible, however, to build the bridge initially for highway traffic only, but with provision, at a small extra expenditure, for the future accommodation of rail passenger, or additional bus passenger traffic. In fact the design, as now developed (See Exhibit C), is exceptionally far-reaching in its provision for a gradual increase in traffic capacity with a minimum possible initial expenditure, and with the least possible time of construction before the bridge can be opened to traffic. The plan provides for an initial capacity of two 24-foot roadways which will conveniently accommodate four lanes of vehicular traffic, two in each direction. Two footwalks for pedestrians are also provided for. It is estimated that these two roadways will be sufficient to fill the demand for highway traffic for about ten years after the opening of the bridge. If and when justified by increased volume of vehicular traffic, another four-lane roadway can be added, and used for truck traffic, while the two initial roadways may be reserved for the faster passenger automobiles. It L PROVISION FOR HIGHWAY TRAFFIC ON UPPER DECK INITIAL 006~V CAPACITY 7,- Z4. ft.*~ W F., I- -" 71.1. T go us ULIMTEbf~ CAOATYO I I L~ 11 MEME:v Sk:L 1, r T -. T T in ILJ-,, f I U-iz' - -P-wq - f I I I I -I I I — I I I 40 I PROVISION FOR PASSENGER TRAFFIC ON LOWER DECK II II-L-O.,..,B.,Ff,, ~P-df I I MLaL A u I L=b. Mr 4 - - 1. EME6mill qq um-j " i f I it r I I. I II I 1 I I I 11 L I IiI 2,; I rIlzN U-119 W-W. VIOIW I - I y I I v -I II 1- FII TI fr..L. I I i 10. 11 F —1 - HWDSON RWVR BRDOM T"MAL CJM=CWoO 0 -i I i Exhibit (C) Typical Cross Sections of Bridge TENTATIVE REPORT ON HUDSON RIVER BRIDGE 15 is estimated that the eight lanes will be ample to take care of all vehicular traffic which may be concentrated at this crossing. All of this highway traffic is to be accommodated on an upper deck of the structure. If and when accommodation for rail passenger traffic, or for additional bus passenger traffic, across the bridge becomes necessary, two or four lanes, or tracks, of either form of such traffic can be added on a lower deck. The question as to whether, and to what extent, rail passenger traffic should be provided for on the bridge is still under consideration, and the cooperation and advice of the transit authorities in the two States has been sought in order to arrive at a satisfactory solution. APPROACHES AND HIGHWAY CONNECTIONS Tentative studies for the approaches and highway connections on both sides of the river have been made, but further studies in cooperation with the proper municipal and State highway authorities, are necessary. The studies so far completed indicate conclusively that direct connections of the bridge approaches with important highway arteries, such as Broadway and Riverside Drive in Manhattan, and Lemoine Avenue in New Jersey, are entirely feasible and involve no extensive changes in the street system, at least for many years after completion of the bridge. It would be lacking in foresight, however, not to recognize the fact that when the bridge is to be completed to capacity the vehicular traffic will have grown to such an extent that new arteries will become necessary on both sides of the river, more particularly for that traffic which will flow to and from the bridge in an easterly and westerly direction. While such new arteries will not form part of the bridge project proper, studies are being made with respect to them and with a view to give the bridge a proper setting in the future net of highway arteries. Regarding the structural arrangement of the approaches, more particularly that on the New York side, it should be mentioned that aesthetic considerations have been paramount in developing their design. The New York approach is designed as a short viaduct of monumental appearance which will enhance rather than destroy the good character of the neighborhood (see Exhibit D). The New Jersey approach is designed as a cut through the top of the Palisades so marked at the face of the cliffs as not to destroy the appearance of the latter or to break their natural silhouette. Tracks, if any are provided, will be hidden from view on the approaches. 16 THE PORT OF NEW YORK AUTHORITY ARCHITECTURAL STUDIES The commanding location of the bridge in a charming landscape made it imperative to give prominent consideration to the aesthetic side of the bridge design; in other words, to combine beauty with utility and strength. For this purpose the Port Authority has engaged an eminent architect, Mr. Cass Gilbert, to assist the engineering staff in the preparation of the plans. A statement by the architect on the architectural aspect of the project is appended. ESTIMATES OF COST In view of the incompleted state of the preliminary work and certain as yet unsettled questions, such as provision for passenger traffic, extent of architectural treatment of the bridge and approaches, more accurate appraisal of property and damages, etc., it is impossible to give at the present time reliable cost estimates. Making reasonable allowance for the uncertain features, it is estimated that the bridge can be constructed, ready for the initial highway capacity, at a cost of less than $50,000,000, inclusive of interest during construction, and that it can later be strengthened for the eight-lane highway capacity, and provision for from two to four electric railway tracks, at an additional cost of between $15,000,000 and $20,000,000. FINANCIAL STATEMENT The financial statement following gives, for the years 1933, 1943, 1953 and 1960, the gross revenue and net operating income from vehicles only, based upon average toll rates of 50~, 600 and 70t, respectively, an initial cost of $50,000,000 and an additional expenditure, ten years later, of $15,000,000, as required for the increased vehicular capacity. Net Operating Per Cent. of Gross Revenue Administration Income Available Net Operating from Vehicles Operation for Interest and Income to Year Only Maintenance Amortization Estimated Cost A. AVERAGE TOLL CHARGE 50. 1933 $3,700,000 $ 500,000 $3,200,000 6.40% 1943 5,608,000 750,000 4,858,000 9.72 1953 6,572,000 1,000,000 5,572,000 8.57 1960 6,910,000 1,000,000 5,910,000 9.09 B. AVERAGE TOLL CHARGE 60~. 1933 4,441,000 500,000 3,941,000 8.76 1943 6,730,000 750,000 5,980,000 13.29 1953 7,886,000 1,000,000 6,886,000 10.59 1960 8,293,000 1,000,000 7,293,000 11.22 TENTATIVE REPORT ON HUDSON RIVER BRIDGE 17 C. AVERAGE TOLL CHARGE 70~. 1933 $5,181,000 $ 500,000 $4,681,000 10.40% 1943 7,851,000 750,000 7,101,000 15.78 1953 9,201,000 1,000,000 8,201,000 12.62 1960 9,675,000 1,000,000 8,675,000 13.35 NOTE:-Additional revenue from generated vehicular traffic and from bus- and railpassenger traffic is expected to increase materially the potential net operating income. ACKNOWLEDGMENT The Engineering Staff has been aided in its studies so far made by valuable advice and information from various individuals and organizations to whom due credit will be given at the proper time. The undersigned also take this occasion to express their acknowledgment for the valuable services so far rendered by other members of the engineering staff, more particularly, R. A. Lesher, Traffic Engineer, in charge of traffic studies; W. J. Boucher, Engineer of Construction, and R. Hoppen, Jr., Resident Engineer, in charge of surveys and borings; W. A. Cuenot and A. Andersen, Assistant Engineers, in charge of design studies. Respectfully submitted, (Signed) O. H. AMMANN, Bridge Engineer. Approved: (Signed) W. W. DRINKER, Chief Consulting Engineer. (Signed) WMr. HI. BURR, Consulting Engineer on Bridges.. Approved: J. E. RAMSEY, Chief Executive Officer. : _~.-.1-~.1.1 __ _..IY_-__. -— .. -_..~1..-. —~._.I- _ i _ " 1171 lmu~ IN, '~ " X x:": KINORE~ i999 l;rg.\-~ "C -'" ' E ~: J '":d ~: ~.." ~. t;. "l, 1 * ' - '' i "