Premium
Effects of Flushing Spencer Hydro on Water Quality, Fish, and Insect Fauna in the Niobrara River, Nebraska
Author(s) -
Hesse Larry W.,
Newcomb Brad A.
Publication year - 1982
Publication title -
north american journal of fisheries management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 72
eISSN - 1548-8675
pISSN - 0275-5947
DOI - 10.1577/1548-8659(1982)2<45:eofsho>2.0.co;2
Subject(s) - hydroelectricity , environmental science , fauna , flushing , sediment , hydrology (agriculture) , water quality , fish <actinopterygii> , turbidity , fishery , fish kill , ecology , geology , biology , nutrient , phytoplankton , algal bloom , geotechnical engineering , endocrinology , paleontology
Hydroelectric facilities with a low generating capacity (approximately one megawatt) such as Spencer Hydro on the Niobrara River in Nebraska are important, as referenced by the renewed interest in the revival of many that were deactivated with the advent of large fossil fuel and nuclear generating stations. The water reservoir impounded by the Spencer Dam is shallow and entrapped sediment quickly fills the pond, reducing power generating potential and threatening the internal components of the hydro station. This action requires periodic flushings to allow settled sediment to move past the station, resulting in adverse impacts on water quality, fish, and fish‐food organisms in the 63.3 km of Niobrara River downstream from the dam. Investigations in 1979 revealed unacceptable low levels of DO (3.5‐4.0 mg/liter), pronounced increases in turbidity (>400%) and suspended solids (4‐fold), and a doubling of dissolved solids. Thirty species of fish were affected, with a conservative count of 22,471 dead fish plus others under extreme stress. Young fish were most affected. There also were large changes in the abundance of many species of immature aquatic insects. A series of corrective recommendations are proposed to alleviate the problem and enhance the fishery in the lower river.