The State Historic Preservation Officer is 



Mr. F. Lawrence Oaks 



State Historic Preservation Officer 



Alabama Hi storical Commission 



725 Monroe Street 



Montgomery, Alabama 36104 



(205) 832-6622. 



NAVIGATION CHANNELS 



The navigation channels in Mobile and Baldwin Counties (Table 16) include 

 channels providing access to the Port of Mobile, to smaller ports, such as 

 Bayou La Batre, Bon Secour, and Theodore, and the Intracoastal Waterway, 

 which provides for lateral vessel movement along the coast. The following 

 information was supplied by the U.S. Army Corps of Engineers, Mobile District 

 office (J. Baxter, U.S. Army Corps of Engineers, Mobile, 7 December 1982; 

 pers. comm.; U.S. Army Corps of Engineers 1980a). 



The Mobile Ship Channel requires maintenance dredging on the average 

 every 1.5 years, at which time a total of about 3 million m 3 (4 million yd 3 ) 

 of deposits are removed from the bay channel. In addition, 841 thousand m 3 

 (1.1 million yd 3 ) of this comes from the river portion of the channel. 

 Siltation in the 10 to 12 m (32 to 40 ft) deep river and 12 m (40 ft) deep 

 bay portion of the channel is about 0.3 m (1 ft) per year, whereas the 13 m 

 (42 ft) deep bar channel outside of Mobile Bay accumulates 0.6 m (2 ft) per 

 year. Shipping tonnage by deep-draft vessels into the Port of Mobile 

 increased from 13.1 million metric tons (14.4 million short tons) in 1966 to 

 15.1 million metric tons (16.7 million short tons) in 1975. Barge traffic 

 increased from 7.2 to 14.3 million metric tons (7.9 to 15.8 million short 

 tons) over the same period. 



In Chickasaw Creek, upstream of the Mobile Ship Channel, the 8 m (25 ft) 



deep Chickasaw channel accumulates silt at at the rate of 0.3 m (1 ft) per 



year. Just south of McDuffie Island, the Arlington Channel is 8 m (27 ft) 

 deep and fills at the rate of 0.5 m (1.5 ft) per year. 



The 2.4 m (8 ft) deep Fowl River channel accumulates silt at the rate of 

 0.6 m (2 ft) per year and was last dredged in 1980. The Bayou La Batre 

 channel, 4 m (12 ft) deep, fills in at 0.5 m (1.5 ft) per year and was 

 dredged in 1978 and 1982. 



DREDGE SPOIL DISPOSAL AREAS 



The dredging of new navigational channels in coastal Alabama, as well as 

 the maintenance dredging of the numerous existing channels, generates 

 tremendous volumes of spoil that must be disposed of in an environmentally 

 acceptable manner. There were 206.6 km (128.4 mi) of navigational channels 

 in the area, with a surface area of 1384 ha (3420 acres) in 1974 (Alabama 

 Coastal Area Board 1979). The completion of the Theodore Ship Channel 

 (Mobile quadrangle) has increased this amount by 28.3 km (17.6 mi) and 184 ha 

 (456 acres) . 



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