CHAPTER V. SEWERAGE AND DRAINAQK (Part 3)

of the drain and the foundation so as to support it throughout. By this method the work can be done quicker, and the concrete foundation is not weakened or shaken by cutting hollows across for the sockets. Fio. 20. — Drain sockets resting on foundation ; drain pipe unsupported. If an unyielding foundation is not formed the drain will sink at certain points, forming dips or festoons under- ground, which cause stoppage eventually. These points have been noted often, yet sanitary authorities permit the continuance of the ancient defective and dangerous system. The chief difficulty in securing sound drains lies in the fact that they are laid and hidden underground. The aim of plumbers should be to bring them to the light, and so to arrange their drainage that each portion shall be within easy inspection and cleansing distance. There is no valid defence for the dangerous practice of laying drains dry without staunch joints. Drain-layers, when asked why this is done, say it is in order that the L 146 DOMESTIC SANITARY DRAINAGE AND PLUMBING. pipes may not have to be broken when they are removed or altered! Drains ought to be laid down with the object of fulfilling their purpose of being sound and staunch to carry drainage safely for the health of the householders, rather than with the ulterior object of removing the pipes safely at remote periods to the risk of health in the meantime. Perhaps the open joints may drain the subsoil, but if they admit subsoil water in wet seasons they will allow the escape of liquid sewage to saturate the soil in dry seasons, and at all time>s permit the escape of sewer air in Fio. 21. ^Leaking joint and staunch joint a dangerous manner. Medina or Portland cement with fine sharp sand makes the best drain joint, provided that cement-soaked gaskin be first well packed round end of joint, to hold the pipe concentric in the socket, and to prevent possibility of cement oozing into the drain and forming a hard lump inside. The insufficiency of clay or soft yielding material for jointing has been clearly demonstrated, but it is still tenaciously defended by many professional men on the ground that clay yields if xmequal pressure comes on any part of the drain, and thus saves the pipe from fracture. Here we actually find the dangerous elements of bad foundation expected and calculated upon. With good SEWERAGE AND DRAINAGE, 147 foundation the drain could not yield, even with clay joints. We find the careless filling in of ground over pipes so as to cause unequal pressure looked for; and we find apparent forgetfulness of the fact that if a drain sinks or falls below its true level or inclination it is no longer a safe and reliable drain, but contains, whether fractured or not, dips or hollows which retain the drainage dangerously, and therefore such drain ought to be removed. Clay will of necessity wash away out of the joints, as little by little the passing water disintegrates it. Medina or Portland cement is the best, the easiest obtained, and the most simply applied material for earthenware drain joints. The dangers of this open-joint system are very serious. 1st. The open joints allow the escape of the water which is carrying the solids along, a portion escaping at each opening into the surrounding earth, till the liquid remain- ing is insufficient to carry on the solids, and they are deposited in the drain, and eventually cause a stoppage, which cannot perhaps be cleared until the drain is opened up. 2nd. The soil surrounding the drain becomes saturated with liquid sewage, which decomposes and becomes dangerous. 3rd. The drain is more liable to settle unequally, making hollows underground in which solids accumulate. 4th. The three or four joints nearest to the house under the coal- vault or scullery, being open, allow the foul sewer air to be forced rapidly through them into the house, and thus, owing to the rarefied condition of the house air, the foul air is pressed in day and night, unsuspected and in large quantities. The discharging or sewer ends of the pipe drain under roadways are built into the walls of the public sewer, and these sewer walls are found sometimes so close to the outer 148 DOMESTIC SANITARY DRAINAGE AND PLUMBING. walls of the coal-vault adjoining the scullery as to appear but one wall If breaches occur in these cases, caused either by too careless workmen or by too careful rats, the dangerous effect will be the same in either case. Instead of allowing a mason to build well or ill, according to his humour, round the drain-pipe at its outfall through the main sewer wall, special glazed earthenware blocks should be used in each case, built carefully and neatly into the wall, and the drain should then be laid from them towards the house. These blocks should be splayed to deliver the drainage in the direction of the main sewer current. One most important point in connection with this subject is the proper point or position in front of the houses to which the drain should be laid by the sanitary authority, and left ready for the house drain to be connected with. In the majority of cases coming under the author's observation the drains are laid in from the public sewer to the coal-vault adjoining, and opening direct into the scullery imder the haU steps, and therefore in direct, un- broken connection with the kitchen and the dwelling. Many deaths and much illness have been caused by this dangerous position for entrance of drains, taken in connec- tion with the open joints on the drains. Eats frequently make burrows along the outside of pipe drains at this point to get from public sewer into houses, admitting the foul air also, which neither cat nor trap can catch. The law or the sanitary authority should require all drains to be brought into the open areas in front of houses, and should forbid all direct drain connection under any vaults having direct covered access to the houses. That interceptor traps are required on the lines of drain, SEWERAGE AND DRAINAGE. 149 at some point before they reach the houses, is now generally admitted. If intercseptors choke the fault lies in their over- large size, bad form, defective fitting, or insufficient flush, combined with the total neglect of observation on the part of the householder. There are now several forms of inter- ceptor which in 6-inch and 4-inch sizes will clear every time an ordinary flush is used ; nevertheless they should be fixed and arranged so that they can be easily inspected, and so that any serious stoppage will reveal itself at once on the surface. The fact that the drainage of all the houses in the streets on higher levels must pass by the mouth of your house drain, and that possibly this drainage is further polluted by the drainage from fever hospitals, which also discharges into the public sewers, ought to afford sufficient reason for the importance of placing intercepting sewer-gas traps on private house drains. Their absence frequently allows infectious diseases to spread from house to house; indeed, without interception and thorough ventilation a system of supply for conveying infected drain air into houses exists, similar to that adopted by the waterworks for the purpose of supplying pure water, the only difference being that in the case of polluted sewer air the pipes are nine, six, and four inches in diameter, instead of half an inch, and the supply is unrestricted. Householders can have any amoimt of dangerous sewer air, but pure water must be very carefully and sparingly used, or the water inspector will cut off the supply at seven days' notice! The diameter of interceptors frequently corresponds with the diameter of the drain. Place a 9-inch, a 6-inch, and a 4-inch interceptor of one of the best forms side by side for comparison. You observe the necessarily large, clumsy, unmanageable dimensions of the 9-inch, and the handiness of the 6-inch and 4-inch traps for manipulation, and you can at once see that no ordinary house-flush of two or three 150 DOMESTIC SANITARY DRAINAGE AND PLUMBING. gallons of water would clear the larger trap, and conse- quently that foul deposits would be likely to remain, decomposing dangerously, and finally will choke the trap and drain unless a flushing tank is in use to discharge large bodies of water at intervals through the drain and trap. The Jieed of these interceptors aflPords a very strong reason, therefore, in favour of 4-inch and 6-inch drains over 9-inch. The traps standing side by side ought to convince you. Four-inch traps are now used very generally, even when the house drains are of larger diameter. The 4-inch trap retains one gallon; the 6-inch trap retains two and a quarter gallons; the 9-inch trap retains six gallons. The sanitary authorities do not provide or fix intercepting sewer-gas traps on the section of drain under their control, the ends of the drains are left open, and the option of using interceptors is too often left with the householder; conse- quently drains are being daily laid without interceptors, or with interceptors of too large size and of bad form, which choke in a short time and are worse than useless. Inter- cepting chambers should be placed in the open areas in front of every house, easy of access, and furnished with air-tight iron covers and abundant ventilation. It might be a fair question for consideration whether the sanitary authority or the householder should provide this chamber, but it should be the duty of the sanitary authority to lay the drain from the public sewer in a straight line into the area, in every case also providing and fixing a uniform intercepting sewer-gas trap on the house end, with a splay junction to enable the outer drain to be cleared; while the building of the chamber, together with the house drain and branches, at the house side of the interceptor, should be the duty of the householder. This is common sense; the sanitary authority thus controls and SEWERAGE AND DRAINAGE. 151 Fio. 22. — Dangeroiis drain course throu^ scullery. Fio. 23.— Safe drain course from area to area. 152 DOMESTIC SANITARY DRAINAGE AND PLUMBING. prevents escape of the foul air of their sewers into houses, and no dispute as to position of interceptor can arise, as the angles at which house drains join the intercepting chamber may vary, provided it be in the open area. Nothing, however, that can be done to secure a perfect drain can compensate for the danger incurred by carrying the drain under the scullery and coal-vault to the sewer in place of carrying it across under the open area, or so that an open air space may occur between the house and the public sewer on the line of drain. The diagrams (Figs. 22 and 23) show the common and dangerous course of the house drain, and also the proper and safe course. If you notice, there is an unbroken line of covered-in connection between the public sewer and the house along the course of the drain in one case, while the open area intervenes in the other case. A coal-vault under the footway or road adjoining a scullery, with any door or opening between, is always unsafe and often h^hly dangerous, even without any drain passing under it to the sewer. It is generally preferred as a con- venient coal store by the cook, who thus has not to go out into the air to bring in coals from an outer coal-vault Foul air is always percolating more or less from the public sewers or from leaking gas mains, or from the surface of the street, saturated as it always is with foul matters, through the soil and through the walls and floor and arched roof of such a vault, forced in by the heavier column of cold air outside, upweighing the lighter rarefied column of warm air inside the house. There should be a rigid law that no vault under the road or footpath should have any opening into a house direct; that every subway vault should only be entered from an open area ; and that the wall dividing such vault from the scullery or house should be cemented imperviously, to SEWERAGE AND DRAINAGE. 153 exclude from the house all bad or doubtful air that may find access to the coal-vault. If circumstances are such that the house drain must be laid or remain imder the scullery and this vault, the vault should then be concreted, and the doorway built up and cemented, and an entrance or access hole made through the wall dividing this vault from the next vault off the open area. In a certain locality a strong smell of coal gas was noticed and traced to a coal- vault in the front area where a gas pipe was fixed. The gas company's inspector was sent for, and on arrival said a number of other complaints had been made, and that the smell was caused by gas syphons having been pumped into the main sewer, and when the wind changed, etc, the smell* would go away. On being asked if his explanation did not mean that when syphons were not being pumped a constant supply of sewer gas was being forced into the coal-vault and dwellings, eta, he said he would rather not go into that question as he had already been questioned on the point, and his client had threatened to write to the papers and attack the sanitary authorities, gettii^ his name involved in the controversy. Thus are many palpable faults and dangers allowed to remain through self-interest. The fact still remains that the only proper course for a house drain (when it must pass beneath a house at all) is a straight line from open back yard to open front area, with manhole chambers at each end, and with an inter- ceptor and drain continued from front area chamber to sewer. Pipe drains should never be laid inside old built drains. All saturated foul subsoil should be removed from the premises. When it is possible the drains should be kept altogether clear of the house, without passing under any portion of the floors whatever. 154 DOMESTIC SANITARY DRAINAGE AND PLUMBING. Fio. 24. — Earthenware socket drain-pipe, inferior construc- tion. The strength and impervious quality of earthenware drains is different in every make, and, unfortunately for the contractor who knows his busi- ness and desires to use the best quality, this point is generally passed over and considered un- important. Drain-pipes are drain- pipes— they are hidden under- ground; and so, from this indifference, many honest con- trawits for drain work are lost because other contractors employ inferior drain-pipes at less cost. The fact that these cheaper drains have not sufficient strength, and can stand no ordinary test, is not taken into consideration. Nevertheless, the matter is of great importance, and all first-class contractors should urge the matter on the atten- tion of those who seek their services. We here give illustrations of various ordinary drain connections. Fig. 26. — Earthenware right-angle bend. Fig. 26.— Earthenware right-angle bend, with access socket. Fig. 27.— Earthenware obtuse-angle bend. Fig. 28. — Earthenware syphon trap, with vent socket, P shape. Fig. 29. — Earthenware syphon trap, with vent socket, S shape. SEWERAGE AND DRAINAGE. 155 ^,^fT»TT*, Fio. 30. — Earthenware running trap, with yarious sockets, an obsolete form. Fio. 31.— Earthenware tee-piece for inspection nses only. Fio. 32.— Earthenware short splay junction. Fio. 33.— Earthenware long splay junction. Fio. 34. — Earthenware splay junction, with access socket. Fio. 36. — Earthenware double Fio. 36. — Earthenware Y-piece short splay junction. junction. Fio. 37.— Earthenware treble Fio. 38.— Earthenware reducing way junction. piece. 156 DOMESTIC SANITARY DRAINAGE AND PLUMBING. Many improvoments in the manufacture and design of earthenware drains and connections have been introduced to overcome defects and difficulties, but all novelties should be carefully examined and tested before adoption. Plumbers should take pains to keep their knowledge well up to date, bearing in mind that simplicity in construction is better than complication. The late Mr. Buchan, of Gla^ow, introduced many practical improvements, which are extensively adopted. He designed a drain pipe having a small attached block or seat moulded along with the pipe to raise the pipe above the Fio. 89. foundation and to keep it level and steady. This block, however, adds to cost and weight without securing sufficient advantages in practice to compensate. Fio. 40. This illustration shows another modification of Buchan's drains with longitudinal ribs for support, but the writer prefers and recommends the simple form of well-made, well- glazed, well-laid pipe drain. SEWERAGE AND DRAINAGE. 157 Buchan's access openings, as shown here, are very useful on drains, and may be freely used wherever drains pass across under areas, yards, or open courts. They should be Fio. 42. — Longitudinal section. Fio. 48. — Transverse section. made with air-tight covers ; but are not to be fixed inside of houses, lest the covers might be left negligently open after an inspection. Fio. 44. — Access pipe. Fio. 46. — Access jane tion. Fig. 45. —Access bend. Fio. 47.— Access double junction. The Armstrong access junctions are also much used in house drainage work, and are very strong, well-made, and suitable; they are to be obtained with junctions at any desired angle. The subsoil drainage of every house should be considered 158 DOMESTIC SANITARY DRAINAGE AND PLUMBING. by the plumber as of quite equal importance with the water-closet drainage. The basement subsoil should be rendered as dry as possible. If you are called in to replace a leaking or an old-built drain in or around a house, you should first remember that this old defective drain may have been receiving and carrying away the subsoil water, and keeping the basement