Number Page 



30 Production (net tons) of sand, gravel, and clay in the Alabama 

 coastal region 1977, 1979 123 



CLIMATOLOGY AND HYDROLOGY 



31 Air temperatures in coastal Alabama based on 25 years 



of data, 1955-79 131 



32 Rainfall in coastal Alabama based on 25 years of data, 



1955-79 132 



33 Probable recurrence interval for storm tides in coastal 



Alabama 137 



34 Extreme pressure and wind data of hurricanes recorded along 



the Alabama coast since 1892 138 



35 Hurricane surges in Alabama 1772-1979 140 



36 Average daily flow and mean annual 7-day low flow at 



U.S. Geological Survey stations in coastal Alabama 143 



37 Monthly mean discharges (ft^/s) of streams in the 



Mobile River Basin 144 



38 Monthly mean discharges (ft-Vs) of streams draining 



into Perdido Bay 145 



39 Duration of daily flow and average discharge (ft^/s) 



at gauging stations in coastal Alabama 146 



40 A summary of the watershed area of streams and their 



mean annual discharge into Alabama estuaries 147 



41 Chemical analyses of water from streams in Mobile County . . 148 



42 Chemical analyses of water from streams in Baldwin County . 151 



43 Existing municipal sewage plants, 1977 156 



44 Flow summary of industrial process wastewater discharges . . 157 



45 Water quality classification criteria 158 



46 Average and maximum-minimum values of selected water 



quality parameters, 1974-79 160 



47 Water quality trends in Baldwin and Mobile Counties, 1980-81 164 



48 Mobile section 208 study: summary of water quality data . . 164 



xi ii 



