KITCHEN-SINK DRAINAGE
A necessity in every dwelling is effective disposal of the kitchen-sink slops. This necessity ordinarily arises long before the farm home is supplied with water under pressure and the conveniences that go with it. Hence the first call for information on sewage disposal is likely to relate merely to sink drainage. This waste water, though it may not be as dangerous to health as sewage containing human excrements, is still a menace to the farm well and capable of creating disagreeable odor.
Fig. 16.—How to waste kitchen-sink drainage. A, Sink; B, waste pipe; C, trap; D, clean-out; E, box filled with hay, straw, sawdust, excelsior, coke, or other insulating material; F, 4-inch vitrified sewer-pipe, hubs uphill, and joints made water tight for at least 100 feet downhill from a well; G, 4-inch vitrified sewer pipe, hubs downhill, joints slightly open, laid in an 18-inch bed of coarse sand, gravel, stone, broken brick, slag, cinders, or coke; H, strip of tarred paper on burlap or a thin layer of hay, straw, cornstalks, brush, or sods, grass side down; I, 12 inches of natural soil; J, stone-filled pit. As here illustrated, water is drawn by a pitcher or kitchen pump (K) through a 1¼ or 1½ inch galvanized-iron suction pipe (L) from a cistern (M). The suction pipe should be laid below frost and on a smooth upward grade from cistern to pump and be provided with a foot valve (N) to keep the pump primed. If a foot valve is used, pump and pipe must be safe from frost or other means than tripping the pump be provided for draining the system
The usual method of disposing of sink slops is to allow them to dribble on or beneath the surface of the ground close to the house. Such drainage should be taken in a water-tight carrier at least 100 feet downhill from the well and discharged below the surface of the ground. Every sink should be provided with a suitable screen to keep all large particles out of the waste pipe. An approved form of sink strainer consists of a brass plate bolted in position over the outlet and having at least 37 perforations not larger than one-fourth inch in diameter. Provided a sink is thus equipped and is given proper care and the land has fair slope and drainage, the waste water may be conducted away through a water-tight sewer and distributed in the soil by means of a short blind drain. A simple installation, consisting of a kitchen-sink and pump and means of disposal as described, is shown in [Figure 16].
CESSPOOLS
Where farms have water under pressure an open or leaching cesspool is a common method of disposing of the sewage. Ordinary cesspools are circular excavations in the ground, lined with stone or brick laid without mortar. They vary from 5 to 10 feet in diameter and from 7 to 12 feet in depth. Sometimes the top is arched and capped at the ground surface by a cover of wood, stone, or cast-iron. At other times the walls are carried straight up and boards or planks are laid across for a cover, and the entire structure is hidden with a hedge or shrubbery.
Except under the most favorable conditions the construction and use of a cesspool can not be condemned too strongly. They are only permissible where no other arrangement is possible. Leaching cesspools especially are open to these serious objections:
1. Unless located in porous soil, stagnation is likely to occur, and failure of the liquid to seep away may result in overflow on the Surface of the ground and the creation of a nuisance and a menace.
2. They retain a mass of filth in a decomposing condition deep in the ground, where it is but slightly affected by the bacteria and air of the soil. In seeping through the ground it may be strained, but there can be no assurance that the foul liquid, with little improvement in its condition, may not pass into the ground water and pollute wells and springs situated long distances away in the direction of underground flow.
For the purpose of avoiding soil and ground-water pollution cesspools have been made of water-tight construction and the contents removed by bailing or pumping. Upon the farm, however, this type of construction has little to recommend it, for the reason that facilities for removing and disposing of the contents in a clean manner are lacking.
In some instances cesspools have been made water-tight, the outflow being effected by three or four elbows or T branches set in the masonry near the top, with the inner ends turned down below the water surface, the whole surrounded to a thickness of several feet with stone or gravel intended to act as a filtering medium. Tests of the soil water adjacent to cesspools of this type show that no reliance should be placed upon them as a means of purifying sewage, the fatal defects being constant saturation with sewage and lack of air supply. To the extent that the submerged outlets keep back grease and solid matters the scheme is of service in preventing clogging of the pores of the surrounding ground.
Where the ground about a cesspool has become clogged and water-logged, relief is often secured by laying several lines of drain tile at shallow depth, radiating from the cesspool. The ends of the pipes within the cesspool should turn down, and it is advantageous to surround the lines of pipe with stones or coarse gravel, as shown in [Figure 16] and discussed under "[Septic tanks.]" In this way not only is the area of percolation extended, but aeration and partial purification of the sewage are effected.
Where a cesspool is located at a distance from a dwelling and there is opportunity to lead a vent pipe up the side of a shed, barn, or any stable object it is advisable to do so for purposes of ventilation. Where the conditions are less favorable it may be best, because of the odor, to omit any direct vent pipe from the cesspool and rely for ventilation on the house sewer and main soil stack extending above the roof of the house.
Cesspools should be emptied and cleaned at least once a year and the contents given safe burial or, with the requisite permission, wasted in some municipal sewerage system. After cleaning, the walls and bottom may be treated with a disinfectant or a deodorant.