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estimate the cost of engineering and superintendence, including the time and skill of the proprietor, at less than $5 per acre, even where from 20 to 50 acres are to be drained at once. · 2. Digging the Ditches.-The labor required for the various operations constitutes the principal item of cost in draining, and the price of labor is now so different in dif. ferent localities, and so unsettled in all, that it is difficult to determine a rate which would be generally fair. It will be assumed that the average wages of day laborers of the class employed in digging ditches, is $1.50 per day, and the calculation will have to be changed for different districts, in proportion to the deviation of the actual rate of wages from this amount. There is a considerable advan. : tage in having the work done at some season, (as after the summer harvest, or late in the fall,) when wages are com. paratively low.
The cutting of the ditches should always be let by the rod. When working at day's work, the men will invariably open them wider than is necessary, for the sake of the greater convenience of working, and the extra width causes a corresponding waste of labor.
A 4-foot ditch, in most soils, need be only 20 inches wide at the surface, and 4 inches at the bottom. This gives a mean width of 12 inches, and requires the removal of nearly 24 cubic yards of earth for each rod of ditch; but an increase to a mean width of 16 inches, (which day worknien will usually reach, while piece workmen almost Qever will,) requires the removal of 34 cubic yards to the rod. As the increased width is usually below the middle of the drain, the extra earth will all have to be raised from 2 to 4 feet, and the extra yards will cost as much as a full yard taken evenly from the whole side, from top to bottom.
In clay soils, free from stones or “bard pan," but so stiff as to require considerable picking, ordinary workmen,
after a little practice, will be able to dig 34 rods of Jitch per day, to an average depth of 3.80,- leaving from 2 to 3 inches of the bottom of 4-foot dïtches to be finished by 'the graders. This makes the cost of digging about 43
cents per rod. In loamy soil the cost will be a little less than this, and in very hard ground, a little more. In sandy and peaty soils, the cost will not be more than 30 cents. Probably 43 cents would be a fair average for soilo requiring drainage, throughout the country.
This is about 17 cents for each yard of earth removed.
In soft ground, the caving in of the banks will require a much greater mean width than 12 inches to be thrown out, and, if the accident could not have been prevented by ordinary care on the part of the workman, (using the bracing boards shown in Fig. 28,) he should receive extra pay for the extra work. In passing around large stones it may also be necessary to increase the width. : The following table will facilitate the calculations for such extra work:
CUBIC YARDS OF EXCAVATION IN DITCHES OF VARIOUS WIDTH.
li Yard... 1 Rod....
Yds. Feet. Yds. Feet. Yds. Feet. Yds. Feet. Yds. Feet. i Roma......... 121 184 A ó ś } |
Men will, in most soils, work best in couples,—one shovelling out the earth, and working forward, and the other, (moving backward,) loosening the earth with a spade or foot-pick, (Fig. 41.) In stony land, the men should be required to keep their work well closed up,-excava ting to the full depth as they go. Then, if they strike a stone too large to be taken out within the terms of their contract, they can skip a sufficient distance to pass it, and the digging of the omitted part may be done by a faithful
day workman. This will usually be cheaper and more - satisfactory than to pay the contractors for extra work.
inches deep, and opening
been, in a
Concerning the amount of work that one man can do in a day, in different soils, digging ditches 4 feet die French says: “In the writer's own field, 6 where the pick was used to loosen the lower :"two feet of earth, the labor of opening and ::" filling drains 4 feet deep, and of the mean : “width of 14 inches, all by hand labor, has “ been, in a mile of drains, being our first ex“periments, about one day's labor to 3 rods
“ in length. The excavated earth of such a .“ drain measures not quite 3 cubic yards, “ (exactly, 2.85.)” In a subsequent work, in a sandy soil, two men opened, laid, and refilled 14 rods in one day;—the mean width being 12 inches.*
“ In the same season, the same men opened, “laid, and filled 70 rods of 4.foot drain of “ the same mean width of 12 inches, in the Fig. 41.-FOOT “worst kind of clay soil, where the pick PICK, “ was constantly used. It cost 35 days' labor to complete “the job, being 50 cents per rod for the labor alone.” Or, under the foregoing calculation of $1.50 per day, 75 cents per rod. These estimates, in common with nearly all that are published, are for the entire work of digging, grading, tile-laying, and refilling. Deducting the time required for the other work, the result will be about as above estimated; for the rough excavation, 3} rods to the day's work, costing, at $1.50 per day, 43 cents to the rod.
Grading is the removal of 2 or 3 inches in depth, and about 4 inches in width, of the soil at the bottom of the
ditch. It is chiefly done with the finishing scoop, which, · (being made of two thin plates, one of iron and one of
steel, welded together, the iron wearing away and leaving
* Surely such soil ought not to require thorough draining; where men can go so easily, water ought to find its way alone.
very much affected the cost of the ears, to lay a rod?
the sharp steel edge always prominent,) will work in a very hard clay without the aid of the pick. Three men,the one in the ditch being a skillful workman, and the others helping him when not sighting the rods,—will grade about 100 rods per day, making the cost about 6 cents per rod. Until they acquire the skill to work thus rapidly, they should not be urged beyond what they can readily do in the best manner, as this operation, (which is the preparing of the foundation for the tiles,) is probably the most important of the whole work of draining.
Tiles and Tile-Laying.–After allowing for breakage, it will take about 16 tiles and 16 collars to lay a rod in length of drain. The cost of these will, of course, be very much affected by the considerations of the nearness of the tile-kiln and the cost of transportation. They should, in no ordinary case, cost, delivered on the ground, more than $8 per thousand for 14-inch tiles, and $4 per thousand for the collars, making a total of $12 for both, equal to about 19 cents per rod. The laying of the tiles, may be set down at 2 cents per rod,-based on a skilled man laying 100 rods daily, and receiving $2 per day.
Covering and filling will probably cost 10 cents per rod, (if the scraper, Fig. 39, can be successfully used for the rough filling, the cost will be reduced considerably below this.)
The four items of the cost of making one rod of lateral drain are as follows:
Digging the ditches • • • • • • • • .43
.80 cts. If the drains are placed at intervals of 40 feet, there are required 64 rods to the acre,—this at 80 cents per rod will make the cost per acre,- for the above items,-$51.20.
How much should be allowed for main drains, outlets, and silt-basins, it is impossible to say, as, on irregular ground, no two fields will require the sanie amouut of thie sort of work. On very even land, where the whole sur., face, for hundreds of acres, slopes gradually in one or two. directions, the outlay for mains need not be more than two per cent. of the cost of the laterals. This would allow laterals of a uniform length of 800 feet to discharge into the main line, at intervals of 40 feet, if we do not consider the trifling extra cost of the larger tiles. On less regular ground, the cost of mains will often be considerably more than two per cent. of the cost of the laterals; but in some instances the increase of main lines will be fully compensated for by the reduction in the length of the laterals, which, owing to rocks, hills too steep to need drains at regular intervals, and porous, (gravelly,) streaks in the land, cannot be profitably made to occupy the whole area so thoroughly.*
Probably 74 per cent. of the cost of the laterals for mains, outlets, and silt-basins will be a fair average allow.. ance.
This will bring the total cost of the work to about $60 per acre, made up as follows:
Cost of the finished drains per acre . • $51.20 ! 74 per cent. added for mains, etc. · · · 3.83 Engineering and Superintendence ••'. 5.00 Of course this is an arbitrary calculation, an estimate without a single ascertained fact to go upon,—but it is as
* The land shown in Fig. 21, is especially irregular, and, for the pur pose of illustrating the priuciples upon which the work should be done, an effort has been made to make the work as complete as possible in all particulars. In actual work on a field similar to that, it would not probably be good economy to make all the drains laid in the plan, but as deviations from the plan would depend on conditions which cannot well be shown on such a small scale, they are disregarded, and the sys tom of drains is made as it would be if it were all plain sailing.