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Table 2. Changeslin location of pools2deeper than one m as indicated by station numbers for a dredged reach of the Blacksmith Fork River, Cache County, Utah, 1975-76. January 1975 Apri 1 June January 1976 Apri 1 June September 622 689 758 774 351 390 390 468 533 588 603 622 689 741 741 758 758 390 468 390 468 390 468 468 390 741 640 689 741 640 689 758 lSee Figure 13 for location of stations. 2This reach was dredged in late March and late August, 1975. November, 1971, and except for the portion between stations 30 and 122, has not been altered since. Cross sections were surveyed along more than 1.6 km of stream in spring 1972, not long after this reach was altered by bulldozer. A portion of the area was chosen for study and surveyed in May 1975, shortly after some of it had again been altered with a bulldozer. A final survey was conducted in July, 1976. Thus, the area between cross sections 30 and 122 was altered in 1971 and again in 1975, while the area upstream from 122 was altered in 1971, but not subsequently (Figure 12). At the downstream end of this site, between stations 30 and 61, erosion of the eastern bank widened the stream an average of 4.6 m between 1972 and the, spring of 1975. No significant changes in width occurred between May, 1975 and July, 1976. From station 76 to 122, deposition along the eastern bank formed a gravel bar and erosion along the western bank excavated a deep pool between May and November, 1975 (Figure 17). The stream shifted 5 to 6 m to the west as a result. Just upstream, between stations 137 and 351, and again further up between 411 and 671 (Figure 17) the stream banks were eroded and the bott9m elevation raised by deposition. The eastern bank eroded an average of 1.7 m (maximum 3.4 m at 396) while the western bank averaged 0.8 m (maximum 2.4 m at 168). By July, 1976, deposition had raised 'the stream bed to a level higher than the 1972 level at all but six stations in this reach. Changes of 0.3 m or greater occurred at 12 stations, 10 deposition and 2 erosion. The average change in the area bulldozed twice was a lowering of the bottom by 0.2 m while the change in the remainder was an increase in elevation of the bottom of 0.3 m. The land east of the river from stations 182 to 244 was lower than the water 28