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IMPROVEMENT OF DAN RIVER, VIRGINIA AND NORTH CAROLINA.
HISTORY OF THE IMPROVEMENT.
A survey of the portion of Dan River between Danbury, N. C., and Danville, Va., a distance of about 774 miles, was made in 1879, and the report, with estimates for its improvement for bateau navigation and also for steam navigation by means of locks and dams, may be found in Appendix G 19, Report of Chief of Engineers for 1879; and in Appendix H 15 of the Report of 1880 a modification will be found of the estimate for steam navigation, based upon a depth of 3 feet of water, for six months of the year.
The river and harbor act of June 14, 1880, appropriated $10,000 for improving Dan River between Danville, Va., and Madison, N. C.
The project for the work was in accordance with the estimate above referred to, and contemplated a channel 35 feet wide through ledges, with a depth of excavation of 11 feet in pools and 2 feet on rapids, and a maximum slope on rapids of 10 feet to the mile. When the slope exceeds this grade it may be overcome by the use of cables anchored at the head of the incline-a method employed on European rivers, such as the Meuse, Seine, Saône, Volga, Rhine, Elbe, and others, and which has been introduced into the United States upon the Erie Canal. This method, it is believed, will give 3 feet of water for six months of the year 1860. The project was approved July 13, 1880, and proposals were invited for supplying materials and tools for the work. These having been purchased, work was commenced on the derricks and boats on September 21. One derrick-boat and one scow were completed October 16, and work was begun in excavating rock from the channel October 21. The second derrick-boat and scow were completed November 3, 1880.
Only 50 cubic yards of rock had been blasted, when the low temperature of the water prevented the continuance of rock excavation after the 30th of October, and the work was suspended for the winter. Work was resumed on the 20th of May, 1881, and continued to the end of the fiscal year, June 30, 1881, with only moderate progress, on account of the hardness of the rock and the unfavorable direction of its seams, which prevented effective blasts.
WORK OF THE PAST FISCAL YEAR.
At the commencement of the fiscal year, July 1, 1881, the excavation of rock for the improvement of the channel was in progress near Dan. ville, above the dam which deflects the water of the river into the canal. The rock removed at this point was deposited on this dam so as to extend it to within a short distance of the left bank of the river. The drilling and blasting operations were carried up the river from Danville to Lynch's Shoal (about 24 miles above Danville), where a considerable amount of work was found to be necessary.
The channel between Lynch's Shoal and Dean's Shoal (3 miles above Danville) was completed in the early part of September, and operations commenced at Dean's Shoal.
On the 10th of September the excavation of the channel at Lynch's Shoal was completed. A cut was made through a gravel bar at the lower end of the shoal, and the banks riprapped with stone to prevent washing. Séveral dams were necessary at this point. Some difficulty was experienced in hiring a sufficient number of men for the work.
On September 24 the channel at Dean's Shoal was completed.
The work at Old House Ledge (about 34 miles above Danville) was commenced October 17, 1881. At this date the water was so cold that the men were unable to work in it, and the channel could not, therefore, be entirely completed.
On November 11 the operations were closed for the winter. The work accomplished from the commencement of operations, on May 23, 1881, to the close of work, November 11, 1881, was as follows:
Three miles of channel were completed, and the work on 1 mile in addition was well advanced. The larger part of the rock removed was solid, so that one-half of the force were engaged in drilling all the time. A part of the blasted rock was used in building dams, and the remainder was thrown on the side of the channel, at least 3 feet from the edge, and was placed so that it would not be carried back into the channel by high-water or other means. The top was kept as nearly as practicable at the low-water mark, in order to prevent any drift from collecting at the time of high-water. The following is a summary of the operations of the season:
Cubic yards. Blasted rock removed. Loose rock removed..
186 Gravel and sand removed.
Total material excavated...
Number of holes drilled ...
4, 280 Depth of holes, feet....
6,855 Average depth, feet.
1.36 Average depth of holes per cubic yard of rock blasted, feet.
2.29 Number of boles drilled, feet..
1.65 Giant powder used, pounds.
1, 105 Giant powder used per cubic yard of rock blasted, pounds. Exploders used....
4,482 Exploders used per cubic yard of rock blasted.
1.73 Drill steel used per 100 feet of rock drillod, pounds..
4. 15 or, 1.41 feet of 1-inch drill steel. DAMS WERE BUILT AS FOLLOWS:
of rock. Part of dam at head of canal, Danville, the timber being furnished by parties
controlling the water-power, and the stone placed in position by the United States....
300 1 dam at Station No. 11..
67 3 dams Lynch's Shoal..
170 1 dam at Old Honse Ledge.. 1 riprap wall at Lynch's Shoal.
17 1 log wall at Lynch's Shoal, length in feet..
The estimated cost of blasting and removing the rock (2,776 cubic yards) per cubic yard, not including office work, traveling expenses, or wear and tear of plant and tools, is as follows: Superintendence, including overseers and sub-overseers.
$0 34 Labor, including quarrymen, drillers, blacksmiths, watchmen, and laborers.... 1 98 Giant powder
05 Drill steel. Blacksmiths' coal.
Total cost per cubic yard....
During the winter of 1881-'82 the derrick-boats and property were placed in charge of a watchman. Operations for the season of 1882 were commenced on April 24, a small force being at first employed to remove the boats to the point of operations and to make the necessary repairs. Rock excavation was begun on May 1, 1882.
Owing to high-water and to cool weather, only moderate progress was made with the work.
From May 1, 1882, to the close of the fiscal year ending June 30, 1882, the following work was done:
One thousand five hundred linear feet of channel, 16 feet wide and 2 feet deep, was completed, and 1 dam at Old House Ledge was finished by the addition of 50 cubic yards of stone. Number of holes drilled
1,796 Depth of holes drilled ..
... feet.. 2,519 Amount of rock removed.
621 Cost per cubic yard..
$4.01 Giant powder used
- pounds.. 362 Exploders used, number.
1, 879 Seventeen days were lost from freshets, the highest point reached by the river being 3.7 feet above low-water.
At the close of the fiscal year work was still in progress near the foot of Long Shoals, about 4 miles above Danville, only sufficient funds remaining to continue operations until the 15th of July, 1882.
Appropriations have been made as follows: June 14, 1880.
$10,000 March 3, 1881
8,000 The amount needed for the completion of the work, June 30, 1882, is $34,000.
I would respectfully recommend an appropriation of $15,000 for the year ending June 30, 1884.
The following statistics of trade have been collected by Mr. R. P. Henry, Danville, Va.: Bacon
$83, 850 Beef and other cattle...
51, 600 Coal...
25,000 Dairy products.
8,300 Fish and oysters
12, 160 Furs..
11, 250 Grain.
67, 260 Horses and mules
11, 000 Hogs
15, 900 Iron (bar, pig, and scrap).
126, 000 Lard
6,500 Lumber (sawed)
29, 050 Potatoes ..
20, 790 Sheep and lambs.
3,500 Staves and barrel timber
12, 900 Tobacco
5, 634, 351 Wood.
16, 380 Unclassified..
6, 615, 891