Relations of Main-Stem Reservoir Operations and Specific Conductance in the Lower Arkansas River, Southeastern Colorado

Two main-stem reservoirs on the lower Arkansas River, Pueblo Reservoir and John Martin Reservoir, are used to regulate and manage streamflow for irrigation and domestic water supplies, flood control, and recreation. Water storage and release operations for these reservoirs can affect streamflow and water quality of the downstream river. One water-quality property that can be affected is specific conductance. In 1996, the U.S. Geological Survey completed a study of the effects of Pueblo Reservoir and John Martin Reservoir operations on specific conductance at five sites located on the Arkansas River between Pueblo Reservoir and Lamar (fig. 1). This fact sheet presents an overview of the study findings. A detailed discussion of the study results is presented in Lewis and Brendle (1998).