TOPOGRAPHY AND DRAINAGE. 99 



on its course. These three rivers are always muddy, and 

 navigable all the way across the area under consideration 

 and some distance farther inland. 



The Pea and Conecuh Rivers and Patsaliga Creek head 

 on the south slopes of Chunnennuggee Ridge just south of 

 the black belt, and gather considerable fertility from the 

 soil of the blue marl region before entering the pine hills, 

 and evidences of that are plainly seen far down into the 

 pine hills. These streams are too small to be navigated by 

 any craft but skiffs and launches. 



The remaining streams all rise in the red hills or farther 

 south, and are still smaller, and free from mud at least part 

 of the time. A few in the southeastern part of the State 

 that come from limestone springs have the clear bluish color 

 characteristic of such conditions. Those that are wholly 

 confined to the pine hills are commonly blackish from dis- 

 solved and suspended peaty matter, but the smallest 

 branches are perfectly clear. 



WATER-POWER. 



Many of the creeks have been dammed up to furnish 

 power for sawmills and grist-mills, and on the Pea River 

 in Coffee County there is a hydro-electric plant with a dam 

 28 feet high, developing about 2,500 horse-power, and fur- 

 nishing electricity for Elba and Troy. More recently a 

 similar plant has been built on Omussee Creek near Colum- 

 bia, to supply Dothan with electricity. 



The 'following table of water-power utilized in southern 

 Alabama (Table 21) has been compiled from Bulletin 17 

 of this Survey, a second report on the water-powers of 

 Alabama, by B. M. and M. R. Hall (1916). The location of 

 several of the dams near the line between two regions, with 

 no more exact information in the published list than the 

 name of the nearest post-office, introduces an element of 

 error, but such errors tend to balance each other. It is also 

 very likely that a number of dams built in recent years have 

 not been listed, but that should not materially affect the 

 comparisons between different regions. 



Nearly half the total power included in this table is at 

 the Pea River dam near Elba. Before that was built the 

 average power per dam was 19 horse-power in the eastern 

 division of the red hills and 21 in the whole area. 



