Norwich bulletin., 1916-04-27
DETAILS OF NEW
 THAMES RIVER BRIDGE
Serious Engineering Problems Had to Be Solved in Connection With the Plans.

Many items have been printed in regard to the new bridge which the New Haven road is to build across the Thames, a project in which there is the transportation facilities and win make way for the adaptation of the present bridge to highwal needs by the state of Connecticut
 The work of constructing new bridge over the Thames river by the New York. New Haven and Hartford Railroad Co, Is now actively under | way. The contractors plant is arriv- | ing and the materials for the founda- tions are being assembled as rapidly | as possible.
 ] The new Thames river bridge will take the place of the present struc- ture. which was built in 1888 and 1889. It was originally a two-track | structure, but in 1908, owing to the increase in the weight of equipment, It was necessary to limit the use of the bridge to single track operation. | This section of the New Haven's main line has consequently become one of l it's most difficult points, and the new bridge, therefore, will not only mean a saving in time and an improvement in the service of the New Haven rail- road. but 1t also represents another step in the development of New Eng lands transportation facilities.
 | When the present bridge is finally abandoned by the New Haven 1t will
 be given to the state of Counecrfcut For use as a highway bridge. This will shorten and improve the wagon
 and motor road along the shore line
 to marked degree It is an inter-
 esting commentary on the develop
 ment of transportation in the United
 States that this bridge. which is less
 than three decades old. and which is
 to be abandoned for railway purposes
 should have been at the time of its
 opening one of the connecting links
 of a direct rail connection between
 Boston and New York Prior to its
 construction trains were transported
 across the Thames by ferryboats, and
 before that passengers were required to disembark upon one side of the river. take ferry across, and re- embark upon another train on tnS other side.
 There will be a clearance under the new Thames river bridge of 32 l.. feet. which will permit vessels not re. quiring a greater clearance than thil to pass under the structure at anJ point. For the purpose of accommo, dating masted vessels, a bascule typ, 2 of bridge has been decided upon Thii
 will be operated by electric motorI , to insure quick operation, reducing stallation of these win be dupif ' cate, and power will be taken iron , three sources to insure against a de
 lay to river traffic.
 The foundation of the bridge vii
 for the present, meet all require
 ments. The character of construc : tion will be such that the maximum 2 weights of locomotives may be op 3 erated over it, bringing this poin in the main line of the New Havei
 up to the standard capacity, whicl
 heretofore was limited by the pres ent structure.
 q Upon completion of the new bride q and the construction of the four tracI @ section between Groton and Midway '' 1t Is anticipated that saving of sev
 era1 minutes In time will be effecte
 and the congestion through New Lon a don very materially relieved. Tn
 reconstruction of the New Haven rail
 roda through New London canno t owing to the great cost, be seriousl
 given consideration it will probabl n be on the basis of an elevated strnc n ture through the city, connecting wit
 four track section on the line ter
 minating at Ocean avenue. By bring r ing the four track section to the vi b cinity of New London from eithe
 direction, the congestion and della
 incidental to the operation and train ; will be materially reduced.
 A' Construction of New Piers.
 Construction of the new piers wi ,- follow the most modern method h avoiding the use of pile supports. Tn
 piers adjacent to the channel will ez
 tend to a depth of 142 feet belA- " low water in order to rest upon suit Ie able foundation material. This gres
 depth will be reached by a caisson rs
 sembling an enormous box withoI Ie bottom CT cover. but divided int l. cells by partitions. Throught thes ,s cells the material in the river bed wi
 be excavated by dredging bucket
 The caisson' will sing as the materi, -- is removed and concrete will be adde l. to the caisson until the bottom or cut IS ting edge reaches the solid bearin j. strata At this point the mud an
 clay within the wall of the caisso