102 GEOLOGICAL SURVEY OF ALABAMA. 



On the accompanying profile the stations are one mile apart, 

 and are numbered from zero at the mouth of the river, up to no 

 at the Shelby county line. In the following 1 description of 

 pow:ers that can be developed these mile stations will be referred 

 to as stations : 



Power No. i. From the head of "Half Mile Rapids" at Sta- 

 tion 1 08 there is a succession of shoals known as Half Mile, 

 Long Island, Fish Trap, Ford, Reach, and Dry Creek Shoals, 

 in which the aggregate fall is 30 feet in 2^ miles. There is 

 also a fall of about 4 feet from the Shelby Count v line down to 

 the head of Half Mile Shoal, making a total fall of 34 feet in 

 four miles. This can be developed either by building a dam 34 

 feet high at the mouth of Dry Creek and backing the water to 

 the Shelby County line, or by building a low dam near the head 

 of the shoals, and a canal from it to a point opposite the mouth 

 of Dry Creek. Such a development will give about 500 net 

 horse-power, with an 80% turbine at ordinary low season. This 

 power would be near Blo.cton, Ala. 



Power No. 2. By building a 1 5-foot dam at the head of 

 "Baily Reach Rapids," near Station TOT, and near the mouth 

 of Big Ugly Creek, to back the water to the mouth of Persim- 

 mon branch near Station 104, and constructing from this point 

 a canal along the river bank about four miles long, to a point op- 

 posite Station 97, at the mouth of Little Cahaba River, a prac- 

 tical head of 54 feet can be developed. This allows 8 feet for 

 storage and grade, as the total fall is 62 feet. A 54-foot fall 

 would produce about 800 net H. P. 



The same power can be developed by building a high dam, 

 lower down the river, and having the canal shorter. Or, the 

 power can be divided into two separate powers. This power 

 site is between River Bend and Cadle, in Bibb County. 



Power fJo. 3. From the mouth of Little Cahaba down to 

 Station 88y 2 at the top of Centerville Shoals, there is a fall of- 

 ten feet in 8y 2 miles, and from the top of Centerville Shoals 

 down to the foot of Centerville Shoals at Centerville, there is 

 a fall of 13.6 feet in about i^ miles. This power can be de- 

 veloped by a ten-foot dam at top of Centerville Shoals, and a 

 canal from there to Centerville \y 2 miles long. Allowing 2.6 

 feet for storage and canal grade, a head of 21 feet can be ob- 

 tained which will give 650 net H. P. 



It is probable that a much better method of development will 

 be to erect a dam at Centerville 23.6 feet high to back the 



