Water Quality Changes in Elephant Butte Reservoir

Few investigations of changes in quality of water passing through a large storage reservoir, such as that presented herein, seem to have been made. In addition to the obvious blending of water and dissolved salts by storage, substantial changes to the quality of the reservoir effluent will occur in those basins in which the sediments are readily permeable. Inflows to bank storage naturally carry with them substantially all of the dissolved salts. During falling reservoir stages, most of the more soluble ions are returned by the water released from temporary bank storage while the less soluble ions are all or partially retained in the sediments. The apparent constant relationship between quantity of water in bank storage and weight of dissolved sodium plus chloride ions in solution suggests a check method of measuring magnitudes of bank storages.