A NATIONAL PLAN FOR AMERICAN FORESTRY 447 



of debris deposited by these recent floods were far in excess of any 

 earlier flood action in that locality since Lake Bonneville ceased to 

 exist some 30,000 or more years ago. 



In 1923, for example, disastrous floods occurred at Farmington and 

 Willard, Utah. Mountain sides were gullied, farm property in the 

 valley was destroyed, and six people were killed in Farmington Can- 

 yon. The damage to town and farm property at Willard was between 

 $75,000 and $85,000. Again, in 1930 and 1932 increasing numbers of 

 areas in Davis, Salt Lake, and Utah Counties were flooded. News- 

 papers estimated the damage at more than $1,000,000. The Red 

 Cross report on floods in these counties in 1930 states that 179,200 

 acres of high-priced truck and orchard land was flooded and 295 

 acres of such land rendered completely useless, that 134 families were 

 left homeless. It cost Utah about $100,000 to clear the State high- 

 way. 



By careful examination after the floods of 1930 the Governor's 

 special flood commission established 73a that the silt-laden flood water 

 had collected chiefly on small areas of private land at the heads of the 

 drainages where the vegetative cover had been seriously depleted or 

 destroyed by overgrazing, by fire, and to some extent by timber 

 cutting. This was determined by observing where gullies 10 to 20 

 feet deep led into the main channels. From these large gullies smaller 

 ones radiated out into many tiny channels on almost barren spots 

 where the surface soil had been entirely stripped away through sheet 

 erosion. The steep slopes, at intermediate elevations, that make up 

 the greater part of the mountain face bear a dense brush or forest 

 cover. No gullies originated on these slopes, where the plant cover 

 and thick litter restrained the surface flow sufficiently to permit 

 effective penetration of water into the mellow humus-filled surface 

 soil and prevent undue soil or water losses. The results of examina- 

 tions made in 1931 and 1932, by representatives of the Utah Agricul- 

 tural Experiment Station, the Utah State Land Board, and the inter- 

 mountain Forest and Range Experiment Station, of more than 15 

 recently flooded areas in Utah and the watersheds from which the 

 floods came show a similar relation of cover depletion on small critical 

 areas to rapid run-off and floods. 



Paul and Baker, 74 reporting on the 1923 floods of northern Utah, 

 attributed the floods to destruction of cover at the heads of stream 

 courses. 



That floods in the Great Basin can at least be alleviated is clearly 

 indicated by Forest Service studies on the Manti National Forest, in 

 central Utah. The forest and brush covered slopes and subalpine 

 grassland openings of the Manti Canyon watershed, for example, had 

 been badly overgrazed by cattle and sheep as early as 1890. 

 Reynolds 76 pointed out that 



between 1888 and 1905, the Wasatch Range, from Thistle to Salina, was a vast 

 dust bed, grazed, trampled, and burned to the utmost. 



No flood of consequence occurred in Manti Canyon before 1888, but 

 the canyon discharged serious floods in that year and in 1889, 1893, 



rsa "Torrential Floods in Northern Utah, 1930." Eeport of Special Flood Commission. Utah Agr. 

 Expt. Sta. Circ. 92. 1931. 



?< Paul, J. EL, and Baker, F. S., " The Floods of 1923 in Northern Utah." Univ. of Utah Bui. v. 15, no. 

 3, 1925. 



Reynolds, Robert V. R., "Grazing and Floods: A study of conditions in the Manti National Forest, 

 Utah." U.S.Dept.Agr.For.Serv.Bul. 91, 1911. 



