Table 40. A summary of the watershed area of streams and their mean annual 

 discharge into Alabama estuaries (Chermock 1974, modified from Crance 1971). 



Estuary and a . 

 gauge station 



Mean annual discharge 

 (ft3) 



Watershed 

 area 

 (mi 2) 



Years of 

 records 



Total 



73U76" 



100b 



8.57 

 55.1 

 300^ 



363.67 



12 



15 



Mobile Delta 



Alabama River 02429500 31,870 



Tombigbee River 02470000 36,230 

 East Basset Creek 02470100 276 

 Chickasaw Creek 02471000 275 



Additional 3,715 c 



Totals 



75,189.7 



22,000 



19,100 



188 



125 



2,239 b 



43,652 



394 

 23.2 

 93.2 



507.6 

 1,018.0 



45,133.67 



38 

 32 

 12 

 30 



40 

 3 



17 



a Number after stream is U.S. 

 ^Area estimated by Crance. 

 c Estimated. 



Geological Survey station index number. 



Other criteria such as dissolved oxygen (DO), biochemical oxygen demand 

 (BOD) and bacteria (fecal coliform) present in the water are also indicators 

 of water quality. Low DO concentrations stress or kill fish and other 

 aquatic organisms. BOD is a measure of the quantity of dissolved oxygen, 

 generally in milligrams per liter, used for the decomposition of organic 

 matter by microorganisms, such as bacteria. High BOD rates can result in 

 low-level DO concentrations during periods of high bacterial growth. Fecal 

 coliform concentrations are used as indicators of possible sewage pollution, 

 with the attendant danger of disease transmission. Municipal sewage 



147 



