Report of the Joint board consisting of the Metropolitan park commission and the State board of health : upon the improvement of Charles River from the Waltham line to the Charles River bridge. April, 1894.

  • Massachusetts. Joint Board upon Improvement of Charles River.
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: Report of the Joint board consisting of the Metropolitan park commission and the State board of health : upon the improvement of Charles River from the Waltham line to the Charles River bridge. April, 1894. Source: Wellcome Collection.

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    now considered necessary to rely upon dredging for any deepening in the upper harbor or in the main channel as far down as a point below Castle Island. There are two reasons why, in my opinion, the maintenance of the present currents in the upper harbor is not essential to its preservation. In the first place, the currents at the present time are not strong enough to cause an effective scouring of the bottom, and, in the second place, under the conditions which now exist and which will exist more fully in the future, no considerable quantity of solid matter will find its way into the harbor to cause it to shoal. The materials which may enter a harbor and cause shoaling are : — 1. Sewage and street wash discharged from sewers and O O drains. 2. Silt and other matters brought down by rivers. 3. Material washed from the shores by the waves. 4. Material thrown into the harbor from docks and vessels. In addition to these sources from which new material may enter a harbor, the material in its bottom may be shifted by currents. Under the conditions which prevailed before the main drain- age works of the city of Boston were completed, in 1884, all of the sewage of the city and such portions of the solid matter in the street wash as were not intercepted by catch-basins were emptied directly into the harbor; but since these works were put in operation, practically all of the sewage and a very large proportion of the material washed from the streets have been diverted from the harbor. The lighter matters have been dis- charged through the main sewer at Moon Island into the out- going tide, and the heavier matters have been retained in a deposit sewer, just beyond the pumping station, and removed on scows to a dumping place outside of the harbor. The amount of material removed in scows in 1892 was G,466 cubic yards. When the Metropolitan Sewerage System is put in operation the sewage and a part of the street wash from other cities bordering upon the arms of the upper harbor will also be diverted, so that the discharge of solid matter from sewers and drains into the harbor will practically cease. The second cause by which harbors are sometimes tilled,