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6 It follows, therefore, that in IlI8.IIY river basins the peak dis- charges of IlI8.IIY floods actually decrease after a certain point on the river is passed, although the total tributary drainage area continues to increase. Chart III illustrates this situation. It shows the peak dis- charge of the great flood of 1897 in the Tennessee River from Inoxville to the Ohio River. The I1I8Jd.JnuJa discharge of about 466,000 cubic feet per second was reached near Florence, Alabama about 250 miles above the l1\Outh of the river. The maximum discharge of the same flood at the mouth of the river was only 374,000 cubic feet per second, or a difference of JllOre than 90,000 cubic feet per second. The reason for this great re- duction was the large amount of natural channel storage in the lower 250 ~es of the Tennessee River. This stretch of the river is now occupied by the Picltwick and lentuck;y reservoirs, and the natural storage that so effectively cut down the crest of this flood, is now deep under per- manent lakes, and thus has been destroyed forever. It is obvious that there are two basic factors of great im- portance in controlling floods: 1. The water retentive qualities of the drainage area should be preserved. Practically everything done by man, such as the drainage of' BW8II\pS, deforestation, and destructive farming methods, has the opposite effect. 2. Nothing should be done to reduce the natural Channel storage capaCity of a river basin. Again the works of man, such as the building of' levees without proper plenning, encroachments in the river channels and flood plains, canalization, and the building of dams, all tend to lessen this essential storage capacity, or to modify it with adverse results. The objective of flood control is to protect the lives, property and businesses of the. people living within the flood plains of' rivers and streams.