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Thus within each "cell" the water depth and velocity are considered homogeneous. The number of verticals per transect will vary depending on streambed configuration, width of the stream and complexity of velocity distribution. In general, after the transects, benchmark, and headstakes have been selected and surveyed, a kevlar cable is strung from river left to river right and a Monark flat-bottom boat attached to the cable. A sounding weight is lowered from the bow of the boat by a pulley system to obtain the water column depth and then raised to 0.2 and 0.8 tenths of the total depth for velocity measurements. In shallow areas, less than 2.5 feet, the velocity meter is attached to a top-set wading rod to record velocities at 0.6 depth. The following sequence of activities provides a general outline of the field activities and data requirements of a PHABSINI study after the species and life stages of concern, and study sites have been identified 1. Identify cross sections, mark with headpins (rebar) and fenceposts. These cross sections will represent differing hydraulic characteristics, typical microhabitat conditions (i.e. pools, runs?, and hydraulic controls. 2. Survey a level line loop to determine relative headstake elevations. 3. Install a permanent staff gage that will remain in place over the course of the study. In addition, install a temporary staff gage that can be read before and after each transect measurement. 4. Complete a water surface elevation summary for both banks and each cross section for at least three flow levels. 5. Survey the streambed profile at each transect indicating the extent of vegetation and substrate types. 6. Measure the mean column velocity distribution and determine the discharge for each transect. ~~~ 7. Recheck and record the temporary staff gauge upon completion of velocity measurements. Recheck and record the reading of the 8