Sewer pipe

“ The middle of a frozen pipe should never be thawed first, because expansion of the water confined by ice on both sides may burst the pipe. When thawing a water pipe, work toward the supply, opening a faucet to show when the flow starts. When thawing a waste or sewer pipe, work upward from the lower end to permit the water to drain away. ”

“ The method in use for cleaning a sewer by thrusting a fire hose down it can also be used for flushing sewers. It is an inexpensive and fairly satisfactory method. There is, however, some danger of displacing the sewer pipe because of the high velocity of the water. An easier and safer but less effective method is to allow water to enter at the manhole and flow down the sewer by gravity. Direct connections to the water mains are sometimes opened for the same purpose.
Sewers are sometimes flushed by the construction of a temporary dam across the sewer, causing the sewage to back up. ”

“ Unless the joints are wiped quite smooth, the roughness remaining will serve as a nucleus for the accumulation of hair, shreds of cloth, and other matters which will hold silt and grease, and form in time a serious obstruction. Nothing smaller than six-inch pipe should be adopted for a street sewer. Unless the work is to be most carefully done, for all but the branch lines, [Pg 73] for a population of five thousand, or less according to the fall of the sewer, it will be safer to use eight-inch pipes. These pipes must be laid with great accuracy as to grade and direction. ”

“ Thus, in a large city six-inch sewer pipe may be sold in such large quantities that the freight rate is low and the dealer is satisfied with a small profit on each foot of pipe. In the country districts the dealer sells but little, and feels that he must have a larger profit to compensate him for the expense of keeping the material on hand. Thus, six-inch sewer pipe may be had at prices ranging from six cents up to sixteen cents per running foot, depending on the store from which it is bought. ”

“ All wrought iron and steel pipes must be equal in quality to “standard” and must be properly tested by the manufacturer. All pipe must be lap-welded. No plain black or uncoated pipe will be permitted.
Each building must be separately and independently connected with a public or private sewer, or cesspool, except where a building is located in the rear of the same lot with another building, when its plumbing and drainage system may be connected to the house-drain of the front building behind the house trap and fresh air inlet which shall be used for both buildings if sewer connected ”

“ Fig. 125.—Cradle for Placing Sewer Pipe.
Pipes above 24 to 27 inches in diameter are too large to be handled from the side of the trench. A hook as shown in Fig. 124 is placed in the pipe so that it will be in the proper position when lowered. It is raised by a rope passing through a block at the peak of a stiff-legged derrick which spans the trench, or by a crane. If a derrick is used the rope passes to a windlass on the opposite side of the trench from the pipe. Mechanical power may be used for raising pipes too heavy to be raised by hand. ”

“ Vitrified sewer pipe with hubs facing downhill; the spigot end should be centered
in the hub with a few small chinks or wedges.
Making the joints of the distribution tile demands especial attention. For a short distance on the upper end of each run the tile should be laid with ends abutting; the joint opening should be increased gradually to one-eighth inch and this increased to one-fourth in the last 20 feet of the run. All joints should be protected against the entrance of loose dirt. Four methods are shown in figure 30. The lower end of each run should be closed with a brick or flat stone ”

“ The sewer should be perfectly straight, with the interior of the joints scraped or swabbed smooth. When the joint-filling material has set, the hollows beneath the hubs should be filled with good earth free of stones, well tamped or puddled in place. It is important that like material be used at the sides of the pipe and above it for at least 1 foot. The back filling may be completed with scraper or plow. No running trap should be placed on the house sewer, because it is liable to become obstructed and it prevents free movement of air through the sewer and soil stack. ”

“ If the cellar or basement contains plumbing fixtures, the house sewer should enter 1 to 2 feet below the cellar floor. If all plumbing fixtures are on the floors above, the sewer may enter at no greater depth than necessary to insure protection from frost outside the cellar wall. Digging the trench and laying the pipe should begin at the tank or lower end. The large end of the pipes, called the hub, should face uphill, and the barrel of each pipe should have even bearing throughout its length. ”

“ When a body of water sufficiently large to nearly fill a pipe is discharged into it, it drags air along with it, and exhausts the air in all branch-pipes to a greater or less extent. When this exhaustion amounts to a diminution of the pressure in the pipe of about 1/350, the water in an ordinary trap (with a one-inch seal) will be forced out of it by the pressure of the external atmosphere, or in other words will be sucked out of the trap into the pipe, leaving no water-seal in the trap, and, therefore, allowing free exit for sewer-air. ”

“ It has been found by actual trial that it is not necessary to increase the size of the pipe sewer in exact proportion to the amount of drainage that it has to convey, as each addition to the flow, where drainage is admitted from street openings or from houses, accelerates the velocity of the current, pipes discharging even eight times as much when received at intervals along the line as they would take from a full head at the upper end of the sewer. ”

“ In the case of either large or small sewers, it will be vastly increased if we compel every householder who makes a connection with the sewer, to carry a drain and soil pipe, nowhere less than four inches in diameter, from the point of junction with the main line to the open air above the roof. ”

“ The only advantage in using a flap valve occurs when the pipe is directly connected with a tank sewer below the level of high water, in which case, if the sea water were allowed to enter, it would not only occupy space required for storing sewage, but it would act on the sewage and speedily start decomposition, with the consequent emission of objectionable odours. If there is any probability of sand drifting over the mouth of the outfall pipe, the latter will keep free much better if there is no valve. ”

“ This is constructed in connexion with a manhole into which the end of the high-level sewer is taken and finished usually with a Flap valve. Some distance back along this sewer a wide-throated junction is put in the invert of the sewer, and from this junction a ramp-pipe is taken down to the invert of the low-level sewer, so that the sewage in the upper sewer instead of having a direct fall runs down the slope of the ramp. The ramp-pipe is usually constructed of iron and is of smaller section than the high-level sewer because of the greater fall and pressure. ”

“ These marks are taken only as frequently as may be necessary to keep the sewer in line. An experienced workman can maintain the line by eye for considerable distances. Measurements should never be taken to the top of the pipe in order to determine position and grade as the variations in the diameter of the pipe may cause appreciable errors.
The position and elevation of the forms for brick, concrete, and unit block sewers are located by reference to the grade line, or they may be placed under the immediate direction of the survey party, or by specially located stakes. ”

“ For a district inhabited by 10,000 persons, a 12-inch pipe would afford a sufficient outlet, unless the amount of road drainage were unusually large, and for the largest sewers, pipes of more than 18 inches diameter are rarely used, these doing the work which, under the old system, was alloted to a sewer 6 feet high and 3 feet broad. ”

“ The soil pipe is of cast-iron, and usually four inches in diameter on the inside. It connects, full size, with the water-closet. Most other wastes are of lead, and are usually an inch and a half in diameter. In the soil and waste pipes there will naturally be the odors from the vaults and sewer, or from the foul matter which is in or passing through the pipes. Therefore, there must be means in each waste pipe, which connects a fixture with the main soil pipe, of preventing the passage of gas or air from it into the house. This is done by means of what is called a trap. ”

“ In the larger sewers the distances are sometimes made greater but inadvisedly so, since quick means of escape should be provided for workmen from a sudden rise of water in the sewer, or the effect of an asphyxiating gas. In the preliminary layout the manholes are located at pipe intersections, changes in direction, and not over 300 to 500 feet apart on long straight runs at convenient points such as opposite street intersections where other sewers may enter. ”

“ The necessary outfit to handle all the piping and plumbing on the farm is not very expensive, probably $25.00 will include every tool and all other appliances necessary to put in all the piping needed to carry water to the watering troughs and to supply hot and cold [48] water to the kitchen and the bathroom, together with the waste pipes, ventilators and the sewer to the septic tank. The same outfit of tools will answer for repair work for a lifetime.
Farm water pipes usually are small. There may be a two-inch suction pipe to the force pump, and the discharge may be one and a half inch. ”

“ In every case where a leader opens near a window or a light-shaft, it must be properly trapped at its base.
47. No steam exhaust or blow-off pipe from a steam-boiler will be allowed to connect with any soil or waste pipe, or directly with the house-drain. They should discharge into a tank or condenser, the waste from which, if to be discharged into the sewer through [Pg 34] the house-drain, must be connected on the sewer side of the running trap. ”

“ A mason can lay more bricks per hour in a large sewer than in a small one as there is a smaller percentage of face work, there is more room to work, and it is easier to lay the bricks radially. The number of bricks laid and the rate of progress on various jobs are shown in Table 68.
Concrete Sewers 188. Construction in Open Cut.—In the construction of sewer pipe of cement and concrete one of two methods may be employed; 1st, to manufacture the pipe in a plant at some distance 315from the place of final use, or 2nd, to manufacture the pipe in place. ”

“ When the main sewers are badly constructed, and, as a result, sewer gas is generated and allowed to accumulate, ordinary precautions may be useless in preventing its entrance by some means or other to our homes, and special means and extra precautions must be adopted. But with well constructed and properly ventilated sewers, every architect and builder should be able to devise a suitable system of house drainage, which need cause no fear of danger to health. The glazed stoneware pipe, now made of any convenient size and shape, is an excellent article with which to construct house-drains. ”

“ The openings to the street are frequently made large enough to allow a man to go down to examine or clean the sewers, and are then called “ manholes." Smaller openings, large enough to allow a lamp to be lowered for purposes of inspection, are called “ lamp holes, " and are often built up of vertical lengths of drain-pipe, 6 in. or 9 in. in diameter, and finished at the surface with a cover similar to that used for a manhole but smaller. A length of 150 ft. of pipe sewer is about the limit that can be sighted thgough. ”

“ The outlet is low enough to drain the settling chamber completely. If it is desired merely to force out the sludge, the drain may be brought to the surface under a head of 3 to 5 feet, discharging the sludge into a trench or drying bed, to be applied later to the land. A 2-inch waste pipe about mid-depth of the settling chamber permits drawing off the cleared portion of the sewage to the siphon chamber and from thence through another 2-inch waste pipe into the 6-inch sewer leading to the distribution field. ”

“ The cable is held to the bottom of the sewer by bracing a 2 x 4 upright in the sewer, with a snatch block attached. A trailer is attached to the scoop to prevent loss of material.
Plows and other scraping instruments are dragged through pipe sewers to loosen banks of sludge and detritus and to cut roots or dislodge obstructions. One form of plow consists of a scoop [106] similar to a grocer’s sugar scoop, which is pushed or dragged up a sewer against the direction of flow. As fast as the scoop is filled it is drawn back and emptied. ”

“ Since they usually lie below the ground water level it is inevitable that a certain amount of ground water will enter. Various units have been suggested for the expression of the inflow of ground water in an attempt to include all of the many factors. Some of these units are: gallons per acre drained by the sewer per day, gallons per mile of pipe per day, gallons per inch diameter per mile of pipe per day, etc. Since the ground water enters pipe sewers at the joints, the longer the joints the greater the probability of the entrance of ground water. ”