The Water Supply of the El Paso and Southwestern Railway from Carrizozo to Santa Rosa, N. Mex. | Page 7

day. Tamping and puddling still left a filtration of 12 in. per day, with a tendency to increase. Enough water filtered through the concrete to produce settlement and cracks. Finally, the concrete was water-proofed with two coats of soap, two of alum, and one of asphalt. This has made all the reservoirs water-tight. Elaterite, an asphalt paint made by the Elaterite Paint and Manufacturing Company, of Des Moines, Iowa, was used successfully on the Luna Reservoir. This paint is applied cold, and preliminary tests showed it to be quite efficient.
The analysis of the soil is as follows:
Loss on ignition 3.35 Silica 56.36 Oxide of iron 2.93 Oxide of aluminum 8.97 Calcium oxide 15.95 Magnesium oxide 0.98 Oxides of sodium and potassium 0.47 Carbonic acid 11.35 Sulphuric acid 0.11 Chlorine 0.04 Manganese Traces ------ 100.51 Insoluble matter, 64.50 per cent.
_Pipe-Line Leakage_.--There is no measurable leakage from the iron pipe. By thorough inspection and measurement at the end of two years, leakage on the wood pipe, between Coyote and Bonito Creek, from the 11-and 12-in. pipe, was found to be as follows:
On 8.6 miles, 11-in. pipe, 146,600 gal. per day = 17,046 gal. per mile. " 4 " 12 " " 14,829 " " " = 3,702 " " "
The 7-1/2-in. pipe on this section appears to be leaking less than the 12-in. pipe. Inspection and measurement of it are to be made in a short time.
There is no material leakage from the 10-and 16-in. pipe between Bonito Creek and Nogal Reservoir, as determined by velocity and volumetric measurements hereafter described. The greatest probable error in the velocity measurements would not exceed 1/2 per cent. If such error existed, and was all charged to leakage, it would amount to but 17,204 gal. per day, or 1,582 gal. per mile, out of a daily delivery of 3,784,000 gal.; but the measured discharge of the pipe, as determined by the velocity, was 5.84 sec-ft., while the mean maximum volume of this water over the weir at the end of the pipe is recorded by the weir as 5.88 sec-ft.
From Coyote, east along the railway, the wood pipe is remarkably tight. The rate of leakage from it, as determined by 600 observations uniformly distributed, was as follows:
11-in. pipe = 120 gal. per mile per day. 8-1/2 and 7-1/2-in. pipe = 268 " " " " "
The maximum rate on 1 mile was 1,613 gal. The minimum found was zero.
The observations were made by uncovering a joint and measuring the leakage therefrom for 10 min. A graduated glass measuring to drams was used. The rate of leakage varied from 5 drops to 45 oz. in 10 min. Of the joints uncovered 57% was found to be leaking. It is rather remarkable that, in the large leakage of the 11-and 12-in. pipe between Coyote and Bonito, only one out of every eight joints was leaking. This indicates a physical defect in such joints. The largest leak found on one joint was at the rate of 17[,?]280 gal. per day. Leakage between or through the staves is not measurable, as it is not fast enough to come away in drops unless there is some imperfection in the wood.
The insignificant leakage of 120 gal., stated above, is from the 11-in. pipe in the pumping main between Coyote and Corona. The present maximum working pressure on it is 100 lb. per sq. in. All the figures given above include visible and invisible leakage, the latter being such as does not appear on the surface. The visible leakage is but a small part of the total.
Stopping the Leaks.--Generally, any ordinary leak is readily stopped by pine wedges. Sometimes a loose joint requires individual bands bolted around it. Bran or saw-dust is effective in stopping the small leaks which cannot be reached by the wedges. The good effect of the latter is likely to be destroyed by a rapid emptying of the pipe. If the water is drawn out faster than the air can enter through the air-valves, heavy vacuums are formed down long slopes, and the air forces its way in through the joints and between the staves. The result is that the pipe will frequently leak badly for some time after it is refilled, although it may have been tight previously.
A full pipe and a steady pressure are highly desirable. This doubtless accounts to some extent for the extreme tightness of the wood pipe in the pumping main.
Grade Lines.--The hydraulic grade lines, shown on Plate V, were laid as best fitting the controlling elevations. The various diameters of pipe were determined by Darcy's general formula, with C = 0.00033 for wood and = 0.00066 for iron pipe, checking by Kutter's formula, with n = 0.01 for wood and = 0.012 for iron. These coefficients were taken as conservative and on