SECTION 15 

 FISH-POPULATION STUDIES IN THE OHIO RIVER 

 William C. Klein 



INTRODUCTION 



In 1957 the Ohio River Valley Water Sanitation Commission (ORSANCO) and 

 the Kentucky Division of Fish and Wildlife initiated a 3-year study - 

 Aquatic Life Resources in the Ohio River (ALRP). Chemical fishing in navi- 

 gation locks of the U.S. Corps of Engineers was used as one of the princi- 

 pal methods for collecting the samples to be analyzed. Subsequently, from 

 1968 to 1970, state, federal, and inter-state agencies continued the 

 investigations by cooperative arrangement and gathered data to establish a 

 relationship between trends in the fish population and changes in water 

 quality occurring from the installation of improved wastewater treatment 

 facilities. The goal of these ongoing studies was to provide agencies re- 

 sponsible for water quality management in the Ohio River region with infor- 

 mation necessary for assessing river quality conditions. 



In 1974 ORSANCO began to expand its monitoring program on the Ohio 

 River and the lower reaches of its major tributaries to contribute needed 

 information to these agencies. An important part of the program, biologi- 

 cal monitoring at selected locations, was partially initiated during the 

 fall of 1975; again chemical fishing was used. Some background together 

 with a summary of the methods used and the results obtained from the pre- 

 vious studies, is detailed below. 



THE OHIO RIVER 



The Ohio River is a large canalized stream extending 981 miles from 

 Pittsburg, Pennsylvania, where it is formed by the Allegheny and Monogahela 

 Rivers, to Cairo, Illinois, where it flows into the Mississippi River. At 

 normal pool stages the stream varies in width from approximately 1,000 ft 

 to 4,000 ft in the lower reaches. Flow patterns in the river are extremely 

 variable, ranging from 6,600 cu ft/sec 1 in the upper river to 48,5000 cu 

 ft/sec 1 in the lower reaches. Presently, its depth is controlled by a 

 series of high- and low-level dams and associated navigation locks at some 

 21 locations. The U.S. Corps of Engineers maintains a minimum 9-ft channel 



Minimum 7-day in 10-year flow, 



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