APPENDIX B.

REPORT OF THE DIVISION ENGINEER OF THE BRIDGE AND FERRY DIVISION.

MR. THOMAS F. SULLIVAN,

BOSTON, February 1, 1922.

Commissioner of Public Works:

DEAR SIR-I respectfully submit the following report of the income, expenditures and operation of the Bridge and Ferry Division for the year ending January 31, 1922. The expenditures of the division in the regular maintenance appropriations of the department were $917,425.17. Under a number of special appropriations $970,631.48 was expended, making the total expenditure for the year $1,888,056.65.

BRIDGE SERVICE.

Apportionment of Cost of Bridges between Boston and Chelsea. The City of Chelsea has as yet paid nothing toward the maintenance cost of Chelsea Bridge and Meridian Street Bridge.

Cambridge Street Bridge - Allston Bridge (over the Boston and Albany Railroad).- This bridge should be rebuilt.

Beacon Street Bridge (over the Boston and Albany Railroad). This bridge should be rebuilt.

Chelsea Bridge (over the South Channel of the Mystic river). Work on the rebuilding of this bridge should be begun this year.

Congress Street Bridge. This bridge is antiquated, in bad condition, and should be replaced with a new structure within the next two or three years.

Dartmouth Street Bridge (over the Boston & Albany Railroad). This bridge should have extensive repairs made to make it safe.

Arlington Street Bridge.

The easterly sidewalk of the Arlington Street Bridge over the Boston & Albany Railroad at Arlington square

was rebuilt in March and April of this year.

Some of the brackets were replaced by new ones and considerable patching and strengthening was done, new stringers and floor were aid. The steel work was done by the Transit Department force, woodwork and painting by the Bridge Service force.

Ashland Street Bridge.

The contract which was awarded to the Boston Bridge Works and approved by the Mayor, July 6, 1920, for the reconstruction of the superstructure of this bridge was completed July 7, 1921, at a cost of $54,000.

By the completion of this work a modern steel and concrete bridge, paved with granite blocks and grout jointed, took the place of the old wood and iron bridge.

The new structure is 50 feet wide, with a clear span of 73 feet. Two sidewalks, 6 feet wide, are provided. The new steel deck girders are encased in concrete with a concrete floor slab resting on them. The duct lines. for the Boston Elevated Railway and the Edison Electric Illuminating Company are carried underneath the southerly sidewalk encased in concrete. The westerly approach was regraded and paved with granite block, grout jointed down to Hyde Park avenue,

Bennington Street Bridge.

The floor of the northerly section of the Bennington Street Bridge was rebuilt and the steel work supporting the floor strengthened and painted. A contract was made with John B. Dolan for the rebuilding of the floor. This consisted in removing all wooden stringers on the bridge, planking with 3-inch tongued and grooved planking, water-proofing and paving with wood blocks, with asphalt joints. This work cost $3,047.20. The steel floor beams were strengthened by stiffeners under the stringer bearings and the steel work was cleaned and painted. The steel work and painting was done by day labor forces.

Charlestown and Warren Bridges.

December 6, 1921, W. S. Rendle & Co. was awarded a contract for repairing the fender piers of the Charlestown and Warren Bridges. The face of the draw pier of Charlestown Bridge was repaired by removing vertical planking and placing new wales on the existing piles.

The face of the draw pier of Warren Bridge was repaired with 6-inch vertical plank.

Capsills, stringers, riders', caps, etc., of the piers were renewed where necessary and some piles refitted and refastened.

The entire pier was replanked and fences erected to restrict the areas to be used in the future to smaller dimensions.

The drawtender's house at Warren Bridge was underpinned and the platform which surrounds it rebuilt. This work cost $19,311.67.

Chelsea Bridge North.

The southerly approach to the draw span of the Chelsea Bridge North had settled so low near the draw crack that it was necessary to raise the grade of the street surface to avoid accidents to street railway and vehicular travel. This was done by taking up the granite block paving, raising the curbs with new timber, repairing the under planking and sidewalk planking where necessary and relaying the paving and street railway tracks at the new grades on a deeper sand cushion. The cost of this work was $3,949.95.

Clarendon Street Bridge.

The construction of the new Clarendon Street Bridge over the tracks of the New York, New Haven & Hartford Railroad and the Boston & Albany Railroad was completed May 7, 1921.

A contract was was made with Coleman Brothers, approved on February 9, 1920, for the removal of the old structure over the New York, New Haven & Hartford. Railroad, consisting of brick arches and concrete slabs resting on steel I-beams and girders which formed the original foundation for the Back Bay Hotel, the hotel itself being removed by the railroad company prior to the contract. This work was completed May 4, 1920. A new reinforced concrete abutment was built at the northerly end of the bridge.

The bridge, 60 feet wide and 131 feet long, was then built utilizing the old piers and abutments which formed the foundation of the Back Bay Hotel for other supports. It consists of three spans. The two easterly spans over the New York, New Haven & Hartford Railroad are of steel beams encased in concrete; the westerly span over

the Boston & Albany Railroad has two through plate girders with a floor of steel beams encased in concrete. The pavement is granite block with grouted joints; considerable work was required on the southerly approach, consisting of grading and filling. The roadway of the approach was surfaced with asphalt on a concrete base.

The job was done by the John McCourt Company under contract approved May 24, 1920, and was completed May 7, 1921, at a cost of $115,220.

Columbus Avenue Bridge.

Columbus Avenue Bridge over the Boston & Albany Railroad, a pony truss bridge carrying two roadways, built in 1877 and rebuilt in 1899, has been extensively repaired during the year. The bottom chords of the trusses, the floor beams and sidewalk brackets were patched and strengthened. New stringers and floor plank were laid and some cleaning and painting done. The steel work was done by the Transit Department force, woodwork and painting by the Bridge Service.

Dorchester Avenue Bridge.

On account of decay the westerly sidewalk on the north approach to the draw span collapsed and fell into the channel. This was rebuilt under contract by John P. Cavanagh, with yellow pine underplank and new asphalt surface at an expense to the City of Boston of $3 924.26.

Dover Street Bridge (over Fort Point Channel).

On June 1, 1921, a bad fire destroyed the two middle girders and several floor beams and stringers of the middle span of the Boston approach to the draw span. In the rebuilding the design was changed to allow for a concrete floor slab instead of the original 6-inch yellow pine plank, on which would be placed the granite block pavement. Two new steel center girders were built and new steel floor beams and steel stringers provided in place of those destroyed. A concrete floor slab is to be laid on the steel stringers; the granite paving block to be recut and laid with an asphalt mastic joint. The wooden platform supporting the water pipes under the bridge is to be removed, and a reenforced concrete slab walk substituted. The wooden formwork around the

Edison conduit is also to be removed. Repairs will also be required to shelf angles and floor beams of the other spans. The work of reconstruction will be completed early in the coming year. The work is being done chiefly by day labor forces of the Transit Department.

A damaged section of the upstream draw pier of this bridge was repaired by driving new piles bringing the face of the pier out 15 inches to a straight line. Both faces of the waterway were repaired, as well as part of the surface.

W. H. Ellis & Son Company was the contractor. Work was completed December 12, 1921, at a cost of $2,850.32.

It was found that salt water action on concrete had badly damaged the center draw pier of the bridge. This was repaired by the application of gunite to the eroded portions with a cement gun. Steel reinforcement was placed before the gunite was applied.

The work was done by Maurice M. Devine and completed November 19, 1921, at a cost of $2,078.

Navigation lights have been installed on the Dover street draw which is a swinging span. There are four draw lanterns and five pier lanterns fitted with electric lamps wired with double conductor armored cable. The switches are hand operated and located in the operating cabinet. This work was done under contract by Sterns, Perry & Smith for the sum of $791 and completed December 12.

Hyde Park Avenue Bridge (over Mother Brook).

On September 20, 1921, a contract was approved with the General Construction Company, Inc., for the rebuilding of this bridge. The old steel and wooden bridge is to be replaced by a modern concrete bridge paved with granite blocks. About one half of this work is completed. The estimated cost of doing this work according to the bid is $11,250.

Massachusetts Avenue Bridge.

Massachusetts Avenue bridge over the Boston & Albany Railroad has been stripped and repaired this year. Bottom chords of the trusses, floor beams, sidewalk brackets and bracing were patched and strengthened where badly deteriorated; the lower part of the