Total estimated cost of canal, exclusive of locks. Engineering and contingencies, at 15 percent_-- $569, 800 3,780, 180 429, 830 3, 081, 000 565, 930 721, 380 17, 600 403, 320 42, 520 9, 611, 560 1, 441, 740 11,053, 300 Estimated cost $171, 600 10, 266, 000 1, 435, 000 132, 880 12, 005, 480 1, 800, 820 13, 806, 300 TABLE 37.-Rights-of-way and flowage damages, Summit section Location: Estimated cost Narrows Lock and Dam to Yellow Creek divide cut. $263, 000 Yellow Creek divide cut___. 284, 700 Total estimated cost of rights-of-way and flowage damages – – Overpurchase, surveys and legal costs, at 25 percent.. 547, 700 136, 925 684, 625 1 Bridge over West Fork, Tom bigbee River, opposite waterway mile 407.7. TABLE 40.-Highway relocation 1,449, 000 Epes Lock and Dam to Cochrane Lock and Dam_ TABLE 41.-Rights-of-way and flowage damages, river and canal section Location: Demopolis to Epes Lock and Dam... Canal.... 172, 500 Total estimated cost of rights-of-way and flowage damages_ Overpurchase, surveys, and legal costs at 25 percent- 279, 100 69, 775 175. Summary of cost.-In the following table a summary of the cost of the entire project is given: 348, 875 16, 375 332, 500 Rights-of-way and flowage damages, Summit section_. Transmission line relocation_. Highway bridges__ Highway relocation_ Rights-of-way and flowage damages, river and canal section_ New terminals__ Grand total_:. WATER POWER 176. Potential power. From the summit level or normal pool of Pickwick Reservoir on the Tennessee River to the proposed Demopolis pool there would be a fall of 349 feet, of which 213 feet would be in the summit and lateral canal sections and 136 feet in the river section. The head produced in the summit and canal sections would be only slightly affected by ordinary floods and could, therefore, be well utilized for power development, provided there is a suitable water supply. The natural drainage area above the Narrows lock is only 66 square miles, while the lateral canal intercepts a drainage area of only about 158 square miles. The natural run-off from these areas is not sufficient to provide for lockages and other losses, so that any water used for power development in this section would have to be obtained from the Tennessee River by diversion. 177. In the river section the proposed dams intercept drainage areas of from 1,250 square miles at Bigbee Lock and Dam to 8,697 square miles at Epes Lock and Dam. The minimum flow of record in the river section varies from about 14 cubic feet per second at Bigbee Lock and Dam to about 550 cubic feet per second at Epes Lock and Dam. The records for the Epes gaging station are, however, for a period of only 9 years, and indications are that the minimum flow may be as low as 200 cubic feet per second. Without unwarranted expense any power developments at the river section locks and dams would be run-of-river plants and, since they would be drowned out part of the time, their output would be secondary power. The head at various locks and dams in the river section would be less than 5 feet for 2.5 percent to 10 percent of the time. 178. Development of hydroelectric power in the river section.-Since no primary power would be available in the river section, any power developed at these locks and dams would have to be utilized in an interconnected system. If interconnected with hydro plants having a surplus of power at the time of high water on the Tombigbee River, these plants could possibly increase the prime power of the system to some extent, and the power supplied could be evaluated accordingly. However, for the following estimates it has been assumed that the hydro plants would merely replace steam plants when the water and head were available. In this case the secondary power generated would have a value only equal to the cost of the fuel necessary to produce the same power at a steam plant. 179. It is estimated that coal could be delivered along the river section of the proposed waterway at about $3 per ton for coal with a heat value of 12,000 B. t. u. per pound. If a steam plant develops 1 kilowatt hour from 14,000 B. t. u., a fair average efficiency, the cost of fuel per kilowatt-hour would be: $3.00 14,000 Steam plants located at or near a coal mine could obtain coal at a lower cost, but the cost of transmission of a portion of their output to the area, which would normally be supplied by the proposed hydro plants, would probably bring their cost up as high as or higher than estimated above. 180. On the basis of a value of secondary power of 1.75 mills per kilowatt-hour the economic installation of power facilities at each of the locks and dams in the river section was investigated. Estimates indicate that installations of 6,000 kilowatts each could be made at Epes Lock and Dam and Cochrane Lock and Dam with a small margin of profit. At a lower fuel cost, with possible reduction of the value of secondary power to 1.50 mills per kilowatt-hour, the margin of profit would disappear. At the five locks and dams in the river section with heads of only 15 feet the increased cost of installation per kilowatt would require that the value of the power generated should be at least 2 mills per kilowatt-hour in order to show a saving. Since it is probable that the installation of power facilities at the 15-foot lifts in the river section could not be justified in the near future, further consideration does not seem warranted at this time. On the other hand, the installation of power facilities at the 31-foot and 30-foot lifts at Epes and Cochrane Locks and Dams does seem to be desirable, provided there is a market for the power at 1.75 mills per kilowatt-hour. Because of the narrow margin of justification for these two installations, a definite recommendation of construction at the time of construction of the proposed locks and dams cannot be made without a careful market survey. Since the power installations at these sites would be nearly independent of the locks and dams, such installations. could be made without great additional expense after the construction of the locks and dams, whenever the market warrants. 181. It would be possible to increase the heights of the navigation dams and thereby improve the power possibilities. However, such a course does not appear to be justified. As proposed, the normal pools above the navigation dams in the river section are within the natural stream channel. To derive an appreciable increase in power benefits the navigation pools would have to be raised above the natural banks, thus flooding extensive fertile flood plains 2 to 6 miles in width and increasing greatly the flowage damages. Very expensive spillway structures with long dikes across the valley would be required. Moreover, foundation conditions are not favorable for the construction of high dams. 182. Development of hydroelectric power in the summit and canal sections. Because of the small natural water supply contributory to the summit and canal sections, the only possibility of power development in these sections is contingent upon the diversion of water from the Tennessee River. To justify the diversion of water from the |