George M. Warren

“ The main purpose of home-sewerage works is to get rid of sewage in such way as (1) to guard against the transmission of disease germs through drinking water, flies, or other means; (2) to avoid creating nuisance. What is the best method and what the best outfit are questions not to be answered offhand from afar. A treatment that is a success in one location may be a failure in another. In every instance decision should be based upon field data and full knowledge of the local needs and conditions. An installation planned from assumed conditions may work harm. ”

“ There is a gradual increase in the amount of ammonia and a decrease of free oxygen, the latter going to support bacterial life. When the ammonia is near the maximum and the free oxygen is exhausted the sewage is said to be stale. Following exhaustion of the oxygen supply, bacterial life continues profuse, but it gradually diminishes as a result of reduction of its food supply and the poisonous effects of its own wastes. In the absence of oxygen the bacterial action is spoken of as anaërobic decomposition. The sewage turns darker and becomes more offensive. ”

“ 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. ”

“ Under the most favorable conditions it is unwise to discharge the effluent of a sewage filter in the near vicinity of a source of water supply. Under farm conditions filters are usually neglected or the sewage is improperly applied, resulting in the clogging and befouling of sand filters and the discharge from stone filters of an effluent which is practically as dangerous and even more offensive than raw sewage. ”

“ All personal and realty properties in one eastern city represent a valuation of $10,382 per home, which pays $355 for sewers outside the cellar wall. An average farm in a Middle West State represents a valuation of $17,259. Is not the farmer justified in the small outlay required to dispose of the farm sewage? Because of the issuance of bonds and the apportionment of sewer assessments for a series of years the city dweller may have his burden distributed over a long period. ”

“ Human excrements (feces and urine) as found in closets and privy vaults are known as night soil. These wastes may be flushed away with running water, and there may be added the discharges from washbasins, bathtubs, kitchen and slop sinks, laundry trays, washing vats, and floor drains. This refuse liquid product is sewage, and the underground pipe which conveys it is a sewer. Since sewers carry foul matter they should be water-tight, and this feature of their construction distinguishes them from drains removing relatively pure surface or ground water. ”

“ This method of applying sewage to the soil or subsoil is often spoken of as subirrigation, but subsoil distribution of sewage is different in principle and practice from subirrigation for the increase of crop yields. Subirrigation is rarely successful unless the land is nearly level, the top soil porous and underlaid with an impervious stratum to hold the water within reach of plant roots, and unless a relatively large quantity of water is used and the work is skillfully done. ”

“ Wells and springs are fed by ground water, which is merely natural drainage. Drainage water usually moves with the slope of the land. It always dissolves part of the mineral, vegetable, and animal matter of the ground over or through which it moves. In this way impurities are carried into the ground water and may reach distant wells or springs.
The great safeguards are clean ground and wide separation of the well from probable channels of impure drainage water. It is not [ 8 ] enough that a well or spring is 50 or 150 feet from a source of filth or that it is on higher ground. ”

“ Like plants and animals, disease germs vary in their powers of resistance. Some are hardy, others succumb easily. Outside the body most of them probably die in a few days or weeks. It is never certain when such germs may not lodge where the immediate surroundings are favorable to their life and reproduction. Milk is one of the common substances in which germs multiply rapidly. The experience at Northampton shows that typhoid-fever germs may survive several months in garden soil. ”

“ Disease germs or particles of soil containing such germs may adhere to the skins of vegetables or fruits and infect the eater.
Upon farms it is necessary to dispose of excretal wastes at no great distance from the dwelling. The ability and likelihood of flies carrying disease germs direct to the dinner table, kitchen, or pantry are well known. Vermin, household pets, poultry, and live stock may spread such germs. For these reasons, and also on the score of odor, farm sewage never should be exposed. ”

“ Infection may come from the swirling dust of the railway roadbed, from contact with transitory or chronic carriers of disease, from green truck grown in gardens fertilized with night soil or sewage, from food prepared or touched by unclean hands or visited by flies or vermin, from milk handled by sick or careless dairymen, from milk cans and utensils washed with contaminated water, or from cisterns, wells, springs, reservoirs, irrigation ditches, brooks, or lakes receiving the surface wash or the underground drainage from sewage-polluted soil. ”

“ Sewage or impure drainage water should never be discharged into or upon ground draining toward a well, spring, or other source of water supply. Neither should such wastes be discharged into 'Openings in rock, an abandoned well, nor a hole, cesspool, vault, or tank so located that pollution can escape into water-bearing earth or rock. Whatever the system of sewage disposal, it should be entirely and widely separated from the water supply. ”

“ A tight, underground septic tank with shallow distribution of the effluent in porous soil generally is the safest and least troublesome method of treating sewage upon the farm, while at the same time more or less of the irrigating and manurial value of the sewage may be realized. ”

“ From specific germs that may be carried in sewage at any time there may result typhoid fever, tuberculosis, cholera, dysentery, diarrhea, and other dangerous ailments, and it is probable that other maladies may be traced to human waste. From certain animal parasites or their eggs that may be carried in sewage there may result intestinal worms, of which the more common are the hookworm, roundworm, whipworm, eelworm, tapeworm, and seat worm. ”

“ Any spittoon, slop pail, sink drain, urinal, privy, cesspool, sewage tank, or sewage distribution field is a potential danger. A bit of spit, urine, or feces the size of a pin head may contain many hundred germs, all invisible to the naked eye and each one capable of producing disease. ”

“ No chemicals should be used in a septic tank; garbage, rags, newspaper, and other solids not readily soluble in water should be kept out of sewers and tanks. The plant should be inspected often, noting particularly if the siphon is operating satisfactorily. If scum forms in the settling chamber it should be removed, and the sludge should be bailed or pumped out yearly. Frequently tanks are not cleaned out for three or four years, resulting in large quantities of solid matter going through to the distribution system and clogging it. ”

“ Makeshift methods, materials, or devices should be avoided or used sparingly. Do not place a vent pipe in the top of a cesspool or septic tank if near a dwelling. Siphon chamber and siphon may be omitted in those rare instances where it is feasible to discharge into salt water or into a large stream already badly polluted. Disposal of sewage in a running stream should be a last resort. Such practice endangers water supplies downstream, and unless the volume and velocity of flow are good nuisance may be created in the vicinity. ”

“ 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. ”

“ 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. ”

“ 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. ”

“ The container for a sanitary privy may be small—for example, a galvanized-iron pail or garbage can, to be removed from time to time by hand; it may be large, as a barrel or a metal tank mounted for moving; or it may be a stationary underground metal tank or masonry vault. The essential requirement in the receptacle is permanent water-tightness to prevent pollution of soils and wells. Wooden pails or boxes, which warp and leak, should not be used. Where a vault is used it should be shallow to facilitate emptying and cleaning. ”

“ Farm sewage may contain from 10 to 30 pounds of grease and fats per person per year. This grease, originating mainly in the kitchen sink, hinders septic action and clogs pipes, filters, and soils. Half the grease may be stopped by a septic tank, but the remainder goes into the distribution system, interfering with its action. A grease trap is a device for separating the grease from other wastes. ”

“ A disinfectant or germicide is an agent capable of destroying disease germs; an antiseptic is an agent merely capable of arresting bacterial growth, and it may be a dilute disinfectant; a deodorant is an agent that tends to destroy odor, but whose action may consist in absorbing odor or in masking the original odor with another more agreeable one. ”

“ Sufficient earth should be removed from beneath the hubs to permit the joints to be made in a workmanlike manner.
The house sewer may be vitrified salt-glazed sewer pipe, concrete pipe, or cast-iron soil pipe. The latter, with poured and calked lead joints makes a permanently water-tight and root-proof sewer, which always should be used where the vicinity of a well must be passed; 4, 5, or 6-inch pipe may be used, depending mainly on the fall and in less degree on the quantity of sewage discharged. As a measure of economy the 4-inch size is favored for iron pipe. ”

“ A pit privy for use in field work, consisting of a framework of 1⁄2-inch iron pipe for corner posts connected at the top with 1⁄4-inch iron rods bent at the ends to right angles and hung with curtains of unbleached muslin, is described in Public Health Report of the United States Public Health Service, July 26, 1918.
A pit privy, even if moved often, can not be regarded as safe. The danger is that accumulations of waste may overtax the purifying capacity of the soil and the leachings reach wells or springs. Sloping ground is not a guaranty of safety ”