Chicago Drainage Channel

Washington, Aug. 29.- The board of engineers which recently examined the Chicago drainage channcl with reference to its effect on the lake level submits estimates made by other engineers indicating that a loss of seven indios is possible in Lakes Michigan and Hurón as the effect of the canal. The trustees of the drainage canal contémplate taking only 300,000 cubic feet under present conditions, but after the canal is opened the board aasumes that ultimately the entire 600,000 cubic feet will be drawn from Lake Michigan, as authorized by the state charter. The report says that while the channels and harbors of the great lakes below St. Mary's falls will be injurionsly affected by a diminution in depth, the inner harbor of Chicago will be diminished also by the introduction of a current which, in the present condition of the river with the minimum flow ,of 5,000 cubic feet per second, is entirely inadmissable. The estímate of the effect of the canal on this harbor should, they say, also consider this clement. The board of trustees have not yet determined upon a plan of treatment of this navigable ehannel, and their plans may, the report suggests, be such as to improve, impair, or destroy its utility as a navigable river.