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constraints of time and budget, macroinvertebrates were not studied at this site. METHODS PHYSICAL PARAMETERS Baseline and Cross Sections A baseline was surveyed with an optical transit parallel to the river and between the high water mark and cultivated or pasture lands at all five study sites. The azimuth of the line was recorded from compass readings to the nearest fifteen minutes, angles in the line were recorded to the nearest minute, and all distances were measured along the baseline to the nearest 0.03 m (0.1 foot). Cross section stations were marked with numbered wooden stakes at intervals of 15.2 m and numbered accordino to the distance from the origin of the line (i.e., station 131 was 131 m fro~ the origin of the line (see Figure 12). In most cases, the cross sections were surveyed perpendicular to the baseline. In instances where they were taken at an angle to the baseline, the angle was measured with a field compass to the nearest degree. In each case the placement of the cross section was marked on the bank opposite the baseline with a stake or some natural marker. Elevations to the nearest 0.03 m and width to the nearest 0.3 m were taken at the cross sections where there was some change in the contour, at the shoreline and at the place where the water velocity was strongest. At the Logan River bulldozed site, the baseline and cross section stations that were surveyed in the spring of 1972 were re-established for this survey. This baseline began at the railroad bridge on the Logan River and continued upstream for 1,692 m. The baseline at the Blacksmith Fork dredged site was established beginning at the 1700 South Street bridge in Cache County, Utah, and continued upstream 1,247 m. This site contained cross sections numbered 335 to 847. At the Blacksmith Fork control site, the baseline began at the bridge on Utah State Highway 165 and continued upstream 550 m. Dense bank vegetation at this site made surveying with an optical level impractical because of poor visibility. Therefore, cross sections in this area were surveyed with the following technique. Fixed stations were established on both sides of the river along the baseline, and the elevations of these stations were measured to the nearest 0.03 m. Cross sections were surveyed by holding the surveyor's chain taut between the two stations. The stadia rod was held vertically against the chain at the point where the reading was to be taken, and the elevation was recorded to the nearest 0.03 m at the point where the chain crossed the rod. The location of the rod along the chain was recorded to the nearest 0.3 m. The baseline at the Blacksmith Fork bulldozed site began at the 1st South Street bridge in Millville, Utah and continued upstream for 592 m. The base- 14