Water conduit

“ To form a conduit with souterasi, we choose sources of water, the level of which is several feet higher than the reservoir by which it is to be distributed over the city. We bring the water from its sources in subterranean canals, slightly declining until we come to the borders of a valley or broken ground. We there raise on each side a souterasi, to which we adapt vertically leaden pipes of determinate diameters, placed parallel to the two opposite sides of the building. ”

“ Some are in operation on small roads in out-of-the-way places, being intended principally to illustrate the practicability of the system and thus assist in promoting its introduction elsewhere, but the system that has been adopted in a commercial way is one in which no attempt is made to shield the conductor from moisture and water, and for its successful operation dependence is placed entirely upon the proper drainage of the conduit. This system is well illustrated in Fig. 27. The plow P carries upon its end two brushes, b b, which are insulated from each other. ”

“ Running water confined within a narrow channel, and so compelled to move with force sufficient to give an energetic scouring to the walls of its conduit, may be trusted to carry with it or to drive before it pretty nearly all foreign matter that may have been contributed to it, but the moment this vigorous current is checked, that moment the tendency to excessive deposit begins. ”

“ AERATION BY DRAINS.
Among the advantages of thorough-drainage, is reckoned by all, the circulation of air through the soil. No drop of water can run from the soil into a drain without its place being supplied by air, unless there is more water to supply it; so that drainage, in this way, manifestly promotes the permeation of air through the soil. ”

“ If the outlet must be so situated as to be at times overflowed, great care should be taken to excavate a place at the outlet, into which any deposits brought down by the drain, may fall. If the outlet be level with the ground beyond it, the smallest quantity of earth will operate as a dam to keep back the water. ”

“ This may be an open channel of earth, masonry or wood, laid at as small a slope as is consistent with the delivery of the necessary supply of water, or it may be a closed cast or wrought-iron pipe, laid at the natural slope of the ground, and about 3 ft. below the surface. In some cases part of the head race is an open channel, part a closed pipe. The channel often starts from a small storage reservoir, constructed near the stream supplying the water motor, in which the water accumulates when the motor is not working. ”

“ At the same time it increases the actual supply. Rain, or the signs of rain, in any part of a canal system ought always to be reported to the other parts. Owing to changes in the channels, to fluctuation in the water level of the river, especially during the night, to rain or to changes in the temperature and moisture of the air and to lack of continuous attention on the part of the gauge reader, particularly at night, there is a constant, though perhaps small, fluctuation in the water level in all parts of a canal. ”

“ Water is pumped down the inner pipe, thus loosening the soil, raising the debris and increasing the speed of driving. The “driven well” for water supply is an adaptation of the drive pipe and put down in the same way. ”

“ When opening the valve in the reservoir, or other chamber, to allow the sewage to flow through the outfall pipe, care should be taken to open it at a slow rate so as to prevent damage by concussion when the escaping sewage meets the sea water standing in the lower portion of the pipes. ”

“ In wet seasons the canals are used as drains and in dry seasons as irrigating-ditches. Canals are built above the level of the land, so that irrigation is easy, and for drainage the water is collected in ditches and pumped up into the canals. ”

“ In one part two conduits, or pipes, of a harder stone than that of the mountain land, of a different nature, delivered each a small stream of clear and excellent water from the rock into the road for the convenience of travellers. ”

“ The water is to come in at high pressure, and run in iron or lead pipes up every house, scale every wall. There is to be a tap in every room, and under every tap there is to be the entrance to a drain-pipe. Where water supply ends, drainage begins. They are to be the two halves of a single system. Furthermore, there are to be numbers of plugs opening in every street, and streets and courts are to be washed out every morning, or every other morning, as the traffic may require, with hose and jet. ”

“ Drains are constructed for the purpose of carrying off from the surface of the ground all superfluous fluid, whether it may arise from want of a proper exit for the rain, from springs rising in the ground to be drained, or from water coming from some higher level. Drains are made in towns to carry off the rain from the surface, and all liquid refuse from the houses. ”

“ A stream having a depth of flow sufficient to immerse solid matter held in suspension, to a certain extent lifts it and carries it forward. The entire surface is also exposed to the action of the current. A stream having an equal velocity but a less depth in proportion to the diameter of the solid matters to be transported, evidently has less transporting power. * * * An amount of sewage which can be properly transported by a circular sewer of a given size, cannot be as efficiently transported by one of larger diameter. ”

“ Whilst the rooms of our house are filled with air, it is otherwise with water, which we require in less degree than air. If we have not the artificial means by which water is brought to our houses, through the pipes of a water company, there is a spring or a pump in the garden; or in the absence of these, a good sound cask, standing at the end of our house, forming a receptacle to the water-pipes that surround it, provides us with a supply of water distilled from the clouds. ”

“ We shall have substituted certainty for chance, as far as it is in our power to do so, and shall have made farming an art, rather than a venture.
[pg 046] CHAPTER III. - HOW TO GO TO WORK TO LAY OUT A SYSTEM OF DRAINS. How to lay out the drains; where to place the outlet; where to locate the main collecting lines; how to arrange the laterals which are to take the water from the soil and deliver it at the mains; how deep to go; at what intervals; what fall to give; and what sizes of tile to use,—these are all questions of great importance to one who is about to drain land. ”

“ But it is claimed that drains may be made to promote circulation of air in another way, and in dry times, when no water is flowing through them, by connecting them together by means of a header at the upper ends, and leaving an opening so that the air may pass freely through the whole system. ”

“ If it meet a flat layer of gravel lying upon clay, and having a free outlet, it will follow the course of the gravel,—laterally,—and find the outlet; if it meet water which is dammed up in the soil, and which has an outlet at a certain elevation, as at the floor of a drain, it will raise the general level of the water, and force it out through the drain; if it meet water which has no outlet, it will raise its level until the soil is filled, or until it accumulates sufficient pressure, (head,) to force its way through the adjoining lands, or until it finds an outlet at the surface. ”

“ Thus, by this simple agency of evaporation, the vast quantities of water that are constantly flowing, in all the rivers of the earth, into the sea, are brought back again to the land, and so the great system of circulation is maintained throughout the ages. ”

“ Unexpected Situations.—When unexpected or uncertain conditions are encountered in construction the engineer should visit the spot at once and should advise or direct, according to the terms of the contract, the procedure to be followed. Such conditions may be the encountering of other pipes, quicksand, rock, etc. Each case is a problem in itself. Water, gas, telephone and electric wire conduits can be moved above or below the sewer being constructed with comparative ease. ”

“ In the ordinary English system of upward or drainage irrigation, ditches are dug all round the field. They act the part of conductors when the land is to be flooded, and of main drains when it is to be laid dry. The water flows from the ditches as conductors into built conduits formed at right angles to them in parallel lines through the fields; it rises upwards in them as high as the surface of the ground, and again subsides through the soil and the conduits into the ditches as main drains, and thence it passes at a lower level either into a stream or other suitable outfall. ”

“ From the pumps and the reservoirs there are great pipes which lead the water under the streets to many thousands of houses which compose the city. After the water has been used it is turned into the sewers, runs down into the river and back to the sea, where it is evaporated, rises again in the clouds, and by the wind is carried hundreds of miles over the country. Then it descends again in the form of snow and rain, soaks down through the earth and finds its way again into the springs and great veins of water under the earth, from which it is carried back once more to the city. ”

“ At night, however, and out of working hours, few faucets are open, less water is drawn off at any one time, and the intricate pipes are constantly full of water under high pressure. At such times, a good flow is obtainable even on the uppermost floors. ”

“ When water can be had under sufficient head to thus feed itself into the system, and the hot-well can at the same time be so situated as to drain itself, it makes a remarkably simple and efficient arrangement. ”

“ The drainage of the whole tract irrigated by a canal must be carefully seen to. The subsoil water level of a tract of country is nearly always raised by an irrigation canal. The rise near to a canal or distributary is due to percolation from the channel and is inevitable. [3] The rise at places further away, if it occurs, is due to over-watering or to neglect of drainage. ”

“ It has been found by experiment that in a flat bottomed sewer, four feet wide, having a fall of eight inches in one hundred feet, a stream of water one inch depth, runs very sluggishly, while the same water running through a 12-inch pipe, laid on the same inclination, forms a rapid stream, carrying away the heavy silt which was deposited in the broad sewer. ”

“ In imitation of the circulation of the blood, a variety of pipes and canals perforated all the solid workmanship in such a manner that a continued succession of water could be conveyed to every part of the structure, a number of pumps being adapted to afford an unlimited supply. ”

“ In mountainous country where rivers are comparatively small and their courses are marked by numerous falls and rapids, it is generally necessary to utilize the fall of a stream through some miles of its length in order to get a satisfactory development of power. To reach this result rather long canals, flumes, or pipe lines must be laid to convey the water to the power stations and deliver it at high pressure. ”

“ Sometimes the main conduits are made of lime-mortar, as in the island of Jerbah. The field to be irrigated is divided into small squares or compartments, sometimes oblong of about seven by five feet in size; each is edged up with a small embankment of earth; between each line of squares run parallel ducts or gutters of earth, communicating with one large and common conduit, which is usually placed, to run better, on the highest part of the field, and as nearly as possible cutting it into halves. ”

“ Advantage is taken of the natural water power created by the lock to establish by the side of it an accumulator for operating the gates and valves by hydraulic pressure—in the same manner as at the London and Liverpool docks—which works admirably. ”

“ The conducting of the water through lead pipes is to be managed as follows. If there is a regular fall from the source to the city, without any intervening hills that are high enough to interrupt it, but with depressions in it, then we must build substructures to bring it up to the level as in the case of channels and conduits. ”

“ For only a fish can exist in a hose or pipe completely filled with water, and that is what the tunnel would become if the water rose to the roof—merely a great, underground rocky pipe for the conveying of the liquid from Pocut River.
So you can easily imagine with what anxiety Bud, Nort and Dick watched the rising water. Every now and again one of them would lean over the ledge, swinging the lantern to and fro, so its gleams would be reflected in the hurrying, foaming stream, and indicate how fast it was rising. ”

“ Could a line be graded so as to give a regular inclination from the Fountain Reservoir to one at the city, then the expense of laying iron pipes for conducting the proposed quantity of water, would be greater than for constructing a channel-way of masonry; and when laid, the pipes were thought to be less durable. Should the pipes follow the natural undulations of the ground, there would be so much resistance offered to the flow of water that the discharge would be diminished in a very great degree. ”

“ The kind of water system, like the supply, is governed by geography and geology. If there happens to be a spring on a nearby hillside somewhat higher than the house, nature has provided the cheapest and simplest system. A pipe line and storage tank are all that are needed. Gravity does the rest. On the other hand, if the spring is on the same level or lower than the house, a pump must be added to the equipment to force the water into the pressure tank and out of the faucets. If the spring has a large flow and adequate drainage, a water ram is advisable. ”