It is at the same time made the duty of the Board to represent the existing conditions, and to ask for the necessary appropriations required to supply the needs and to "provide a sufficient supply of pure water" for the various cities and towns constituting the Metropolitan Water District and for the inhabitants thereof. The Board, in its abstract of the Annual Report, which was laid before the Legislature on the third Wednesday in January, enumerated the various objects of construction for which it deemed necessary to make provision during the current year. These, as set forth upon a preceding page, included the construction of a new 48-inch main from Chestnut Hill Reservoir to the Boston line, more especially for the relief of the low-service district of the city of Boston. The Board also stated that it was believed that the time had come when it should take measures to utilize the opportunities for generating power at the Wachusett Dam, as contemplated by the Metropolitan Water Act. If the present rate of water consumption continues unchecked for one or two years longer, it will undoubtedly be necessary to proceed to lay a second 48-inch main from the terminus of the Weston Aqueduct into the Metropolitan District, and to make extensive additions to the pumping plant at Chestnut Hill. In like manner further pipe lines will be absolutely required in the northern part of the Metropolitan District. It is hoped that the Board will be able during the coming year to effect a settlement, through the courts or otherwise, of the various suits and claims brought in connection with the Water Works for damages still unadjusted on account of the construction of the Wachusett Dam and Reservoir, and on account of alleged depreciation in value of property not taken and injuries caused by the operations of the Board to estates and to established business in towns where the reservoir is located. It is expected that the construction of the extension of the Highlevel Sewer in the South Metropolitan Sewerage District will approach completion during the coming year. The further extension of the sewer through the city of Newton will probably not be required for a few years to come, unless additions are made to the District. The construction of the North Metropolitan System was begun about nineteen years ago, and, on account of the large increase in the population and business of the territory constituting the District and the still greater increase in the amount of sewage which must be received, it is becoming necessary to make considerable enlargements and extensions and to renew some of the works which have reached the limit of their capacity or period of safe operation. The Board has accordingly in its recommendations to the Legislature asked for authority to make additions to the East Boston and Deer Island sewerage pumping stations, and to install and equip additional plants in them. The situation at these pumping stations seems to call most urgently for relief. There are other parts of the system to which relief must be extended in a comparatively short period of time. This is particularly the case with the portion of the Mystic valley main sewer, which receives the sewage of the city of Woburn and town of Winchester. This main sewer has so nearly reached the limit of its capacity that it is inadequate in times of heavy rains to dispose of all the contents of the local sewers, and as a result considerable quantities of the sewage and manufacturing wastes diluted with storm water overflow in different localities through the manholes. The situation is such that a new main sewer in this district will probably soon be called for. The detailed reports of the Chief Engineer of the Water Works and of the Chief Engineer of the Sewerage Works, with various tables and statistics, are herewith presented. Respectfully submitted, HENRY H. SPRAGUE. HENRY P. WALCOTT. JAMES A. BAILEY, JR. BOSTON, February 26, 1908. REPORT OF CHIEF ENGINEER OF WATER WORKS. To the Metropolitan Water and Sewerage Board. GENTLEMEN:- The following is a report of the operations of the Engineering Department of the Metropolitan Water Works for the year ending December 31, 1907. ORGANIZATION. The principal changes in the personnel during the year have been the resignation of Frederic P. Stearns from the office of Chief Engineer, which occurred on February 1, and of Alexander E. Kastl, Division Engineer in charge of the Wachusett Department, on August 20. Mr. Stearns, with Joseph P. Davis and Hiram F. Mills, have been retained to act as consulting engineers upon important questions. The principal assistants employed under the direction of the Chief Engineer at the close of the year were as follows: Elliot R. B. Allardice, Arthur E. O'Neil, William E. Foss, . Superintendent, Wachusett Department. Superintendent, Sudbury Department. Superintendent, Pipe Lines and Reservoirs, Distribution Superintendent, Pumping Stations, Distribution Depart- Division Engineer. Division Engineer. Assistant in Charge of Drafting Department. Office Assistant. . Biologist. Arthur W. Walker,. William W. Locke,. At the beginning of the year the engineering force, including those engaged upon both the construction and maintenance of the works, numbered 48, and at the end of the year 45. There has also been a maintenance force, exclusive of the engineers above mentioned, averaging 234, employed in the operation of the several pumping stations and in connection with the maintenance of the reservoirs, aqueducts, pipe lines and other work. Special gangs of men have been employed in repairing and strengthening the North Dike, in constructing ditches for the drainage of swamps in Holden and Princeton, and in cleaning weeds from the bottom of the unfilled portion of the Wachusett Reservoir. The number of men employed on construction, exclusive of those employed by contractors, has averaged 93. ARRANGEMENT OF REPORT. The arrangement which has been adopted in the reports of previous years is followed in continuing this report, and the work charged to the construction account is kept separate from that charged to the maintenance account; but, as the work of construction and maintenance is supervised by the same principal engineers, and in very many cases the assistants are engaged upon both classes of work, it is not feasible to make a complete separation. CONSTRUCTION. GENERAL STATEMENT. The principal work of construction in progress during the year has been in connection with the repairs and reinforcement of the North Dike, the construction of ditches for the drainage of swamps on the Wachusett watershed in Holden and Princeton, the installation of electric lighting, pumping and hoisting machinery at the Wachusett Dam, the final cleaning of the bottom of the Wachusett Reservoir between elevation 375 and high-water mark, the completion of the Arlington pumping station, including the installing of pumping engines, boilers and piping, and the installation of an additional boiler at the high-service pumping station at Chestnut Hill. A detailed statement of the contracts made and pending during the year is given in Appendix No. 1. The following statement gives a summary of all the contracts charged to construction from the beginning of the work to the end of the year 1907: PORTION Of Work. Number of Approximate Wachusett Reservoir, Wachusett Dam, Relocation Central Massachusetts Railroad, Sudbury Department, reservoir, filter-beds, pipe lines and improvement of Lake Cochituate, Metropolitan Water Works contracts, Weston Aqueduct and Reservoir, Distribution Department, including pipes, valves, and special castings purchased for other departments, . Amount of 2 contracts made in 1907 (approximate), $11,934 00 15,240 00 50,585 96 WACHUSETT RESERVOIR And Dam. On the afternoon of April 11 an earth slide occurred at the North Dike of the Wachusett Reservoir, at which time 60,800 cubic yards. of material from a section of the dike about 700 feet long slid into the reservoir. The slide occurred at the highest portion of the dike, where the artificial embankment was about 80 feet high and 1,930 feet thick at the base. The depth of the water in the reservoir in front of the embankment at the time of the slide was about 42 feet. The dike, at the point where the slide occurred, had been constructed with a water-tight core 100 feet wide, the nearer edge of which was located about 50 feet back of high-water line. This core was composed of soil stripped from the reservoir, deposited in 6-inch layers and rolled, and was protected on the reservoir side by an embankment of sand and gravel. The embankment was faced with heavy riprap, stones screened from gravel, and coarse gravel; the heavy riprap extending from 5 feet above to 12 feet below high-water mark, the stones from the foot of the riprap for a further depth of about 12 feet, and the coarse gravel below to the foot of the slope. The |