Cross-section channel profiles, sediment transport and hydrologic data have been observed (before and after closure of the dam) and computed for a series of investigations from 1970 to 1975 at 37 cross sections established along a 59 mile (95 kilometer) study reach from Cochiti Dam to Isleta Diversion Dam, N. Mex.
Cochiti Dam began impounding water in November 1973. Because the dam will trap virtually all of the sediment load originating upstream and water discharge will be controlled, it is expected that equilibrium values of channel width, depth, slope and sediment-transport capability in the existing main stem of the Rio Grande will change. Changes in cross sections with time and space and changes in size distribution of sediments are documented.