Sewage Disposal on the Farm, and Protection of Drinking Water

Part 2

Chapter 23,773 wordsPublic domain

_Vaults._--Water-tight cesspools should be constructed of hard-burned brick, laid in cement, and having a similar brick or a concreted bottom. The inside and outside surfaces of the brick wall should be coated with a thin layer of cement, and clay rammed in around the wall, to increase its imperviousness to water. It should be vaulted above, and topped by a square or round central opening, covered with stone or iron plate. Cesspools are also made of cast or wrought iron, the joints being made water-tight. Cesspools must be ventilated by two pipes, one rising several feet above ground, the other carried to the roof of the house, barn, or other structure near by. The current will, in most cases, tend down the short and up the long pipe. The latter may be dispensed with and the soil pipe of the house act as a flue, provided all branches are perfectly trapped.

_Irrigation._--The disposal of sewage by irrigation is by far the best method now within reach. Two methods are in use, viz, surface and subsoil irrigation. The first in its most complete form consists in carrying the liquid sewage to a piece of ground set apart for the purpose and carefully underdrained. The sewage is allowed to flow over the ground in shallow channels. The fluid slowly disappears in the soil and enters the drains as comparatively pure water, which may be allowed to flow into a stream. For villages this is the best means of disposing of sewage. Those who as village officials may be interested in this method will find plans of such sewage farms, together with faithful accounts of their operation and the results obtained, in the annual report of the State Board of Health of Massachusetts for 1892, page 559, and same report for 1893, page 563. Suggestions for its application to country houses are given farther on.

For isolated rural homes, or village homes commanding a certain amount of ground around the house, the liquid sewage from water-closets, the kitchen and chamber slops may be disposed of by the simple means of subsoil irrigation, first described by Mr. Moule and subsequently elaborated by Colonel Waring.

The system as used at present in its most successful form consists, outside of the house, of the following parts (see fig. 6):

Two adjoining water-tight receptacles of brick. One of these receives the sewage from the house and is intended to act as a settling chamber for the coarser particles, paper, etc. This communicates with the second receptacle, which receives from it the fluid sewage. This chamber is called the flush tank and is provided with a siphon. When the fluid has reached a certain level, the siphon is set in operation and discharges the contents of the chamber at one time into the subsoil pipes.

From the second cistern a system of subsoil pipes laid over a treeless piece of ground, preferably a lawn, receives and discharges the sewage into the ground. These pipes should consist of porous tiles, 2 inches in diameter and about 1 foot long, laid from 8 to 16 inches beneath the surface of the ground, and with a gentle inclination of 2 or 3 inches for every 100 feet. The tiles should have open joints not less than one-fourth of an inch wide. They are laid upon earthen gutters and the joints are protected above by caps from being clogged with earth. The intermittent discharge of the liquid sewage is quite essential to the successful working of this system. If the sewage is allowed to dribble away into the pipes certain portions of these will become supersaturated with fluid and others will not receive any; the purification of the sewage in the soil is thereby rendered imperfect. The discharge of a large quantity of fluid at one time, besides scouring the system of pipes, fills it more uniformly and distributes the work to all parts of the subsoil system.

The successful construction of such a plant requires the services of someone familiar with it, and it is therefore not necessary for me to do more than call attention to it here as a highly recommended system for homes, especially in villages, where the proper amount of land is procurable and where the sewage must be disposed of in a manner both inoffensive and safe. In any case the soil of such land must be porous, not clayey and retentive. Those who wish to familiarize themselves with the details will find descriptions in the Sanitary Engineer for 1883, page 530, by Philbrick; in "The Disposal of Household Wastes," by Gerhard, and in "Sewerage and Land Drainage," by Waring. The entire plant is said to cost $200 to $300, the annual expenditures for cleaning, repairs, etc., about $10.

The method of subsurface irrigation just described may be too complex and too expensive where land is abundant and neighboring houses at some distance. The simpler method of surface irrigation may be resorted to by laying out at some distance--at least 100 feet--from the house a small sewage farm where the sewage may flow in shallow trenches over the surface and slowly sink into the ground. Such an irrigation field must have the same qualities demanded by subsurface irrigation. Its surface should have sufficient slope and the soil should be porous, not retentive. The liquid sewage, including kitchen and chamber slops, is conducted to this field in a water-tight tile drain and then allowed to flow into shallow trenches. To avoid the overloading of the soil with sewage at any one place the main distributing trench should be so arranged that it and the irrigating trenches branching from it may be temporarily blocked at any point to divert the sewage into one or more different trenches every day. In winter the warmth of the sewage will keep it in motion and the filtration will go on although the field may be covered with snow and ice. The use of the flush tank as described above would cause a more uniform distribution of the fluid over the field and make the filtration distinctly intermittent. The ground between the trenches may be cultivated to increase the amount of evaporation. If conveniently situated, an orchard may be used as the irrigation field. It should be distinctly understood, however, that marketable fruits and vegetables should not be carelessly allowed to come in contact with fresh sewage, nor should the irrigation field be near the well unless the latter is fairly deep and tubed or tiled to the surface of the water.

KITCHEN AND CHAMBER SLOPS.

The removal of kitchen and chamber slops is a matter which also requires proper attention, as this liquid frequently gives rise to unhealthful conditions, annoying alike to sight and smell when carelessly disposed of. The simplest way to utilize kitchen slops is to pour them upon plants about the house in summer, in winter upon the soil, each time in another spot, so as not to supersaturate the surface layers of soil in any one place. A means of less trouble recommended by Waring is to partly fill with soil a barrel with leaky bottom and cover this with a layer of stable manure to prevent the puddling of the soil. The slops filter through the soil and leave the barrel below as a clear fluid. The barrel is emptied two or three times a year and the contents used for fertilizer.

House slops may be disposed of by surface irrigation or by subsoil pipes, as already described. The originator of this method, Mr. Moule, may here be profitably quoted as to its simplicity and success:

Where there is a garden the house slops and sink water may, in most cases, be made of great value and removed from the house without the least annoyance The only requirement is that there shall be a gradual incline from the house to the garden. Let all the slops fall into a trapped sink, the drain from which to the garden shall be of glazed socket pipes well jointed, and emptying itself into a small tank, 18 inches deep, about a foot wide, and of such length as may be necessary. The surplus rain water from the roof may also enter this. Out of this tank lay 3-inch common drain pipes, 8 feet apart and 12 inches below the surface. Lay mortar at the top and bottom of the joints, leaving the sides open. If these pipes are extended to a considerable length, small tanks about 1 foot square and 18 inches deep must be sunk at about every 20 or 40 feet to allow for subsidence. These can be emptied as often as required, and the deposit may be either mixed with dry-earth or be dug in at once as manure. The liquid oozes into the cultivated soil, and the result is something fabulous. * * *

On a wall 55 feet in length and 16 feet high a vine grows. A 3-inch pipe runs parallel with this at a distance of 6 feet from it for the entire length. The slops flow through this pipe as above described. On this vine year after year had been grown 400 well-ripened bunches of grapes, some of the bunches weighing three-fourths of a pound. During a period of four years, for a certain purpose, the supply was cut off. To the surprise of the gardener scarcely any grapes during those years appeared; but afterwards the supply was restored, and the consequence was an abundant crop, the wood grow fully 16 feet, of good size and well ripened.

In place of an indoor sink, an upright tube or hopper may be constructed out of doors in communication with the subsurface pipes into which the waste fluids are poured.

WASTE AND GARBAGE.

The attractiveness of a rural home depends largely upon the promptness with which all kinds of waste material are disposed of. The abundance of space around the house is a great temptation for the members of the household to use it as a place for storing rubbish and useless, worn-out things. Sifted ashes are easily utilized in earth closets and upon walks and roads, to make them compact and firm. Other articles of no use, such as broken crockery, bottles, tin cans, etc., can be thrown into depressions and gullies and covered over with earth, or else buried in trenches where subsoil drainage is desirable. The removal of rubbish is a very fruitful theme and might be dealt with at length. Its importance as related to health and disease is a subordinate one, and the reformer must appeal to the love of order, propriety, and beauty in and around the home in order to make an impression.

Garbage is of much less annoyance in the country than in the city, where its collection and destruction is a great expense, and is frequently very unsatisfactorily done. In the country, the household garbage is fed to the swine and poultry, and is in this way profitably used. There are, however, homes where garbage must be taken care of in other ways. It may be buried in the garden or else burned in the kitchen range. Recently a device has been patented which enables the housekeeper to place the garbage in a section of the smoke pipe of the range, where it dries out rapidly, burns, and leaves only a little charcoal behind, which may be used for fuel next day. This device has been well recommended by sanitarians (see fig. 8).

PROTECTION OF DRINKING; WATER.

The next subject to claim our attention is the protection of the sources of drinking water. In the country water is, as a rule, obtained from wells and springs. The important bearing upon well water of soil purity demands a few explanatory remarks concerning the origin of well water. Wells are excavations made into the ground to a variable depth until water is reached. This water is denominated ground or subsoil water. Its origin may be better understood if, for the moment, we conceive the surface of the earth as more or less irregular and entirely impervious to water. The rain would collect on this surface and form lakes, ponds, and streams, according to the configuration of the surface. If, now, we conceive this surface covered with sand or other porous earth to a greater or lesser height, and the top of this be considered the earth's actual surface, the water will remain in the same position, but it will be buried within and fill the pores of the overlying soil as subterranean lakes, ponds, and streams. In digging a well we remove this porous layer of earth until we reach these subterranean streams or reservoirs of ground-water. If the above description be thoroughly understood, the condition under which well water may be obtained at different depths will become intelligible, and it will also appear plain why ground-water may flow as any surface stream and pick up on its way various substances which have percolated into the ground.

When the bed of porous soil overlying the impervious layers is very deep, wells will have to be dug down to a considerable depth to reach the surface of the ground-water. Where this layer of pervious earth is of slight thickness wells will be shallow, and the ground-water may appear on the bottom of gullies, trenches, and wherever the porous layer has been dug or washed away.

The movement of the ground-water depends on the inclination or slope of the impervious strata, and has been observed to be quite rapid in some instances. By adding common salt to the water in a well its detection in other wells at a short distance has been found a guide in the determination of the rapidity and direction of the underground current.

When the ground-water resting on the uppermost impervious layers is near the surface, and therefore not safe or fit to use as drinking water, it may be possible by digging below this layer to find another porous bed containing water. This source will, in general, be much purer since it is less exposed to pollution from above, and since the water has to travel longer distances underground. Such a deep supply must, however, be protected from the superficial supply by a water-tight wall extending to the surface of the deep supply, otherwise the water from the upper layers will simply drain into the well.

WAYS OF CONTAMINATION.

Wells are exposed to contamination in two ways. The surface water from rain, house slops, and barnyard drainage may find its way into the well at or near the surface of the ground. Or the ground-water stream supplying the well with water may in its subterranean movements encounter cesspools or seepings from cesspools, and carry with it soluble and suspended particles, some of which may enter the well. There can be no doubt that a large percentage of the wells are exposed to contamination with refuse matter in the manner described; and it now remains to gauge the danger to health and life which may be carried in the contaminating substance. The danger of typhoid-fever bacteria entering the water has already been mentioned. These may be washed in from the surface or they may pass from cesspools near by through fissures in the ground, passages dug by rats, etc. Whether such bacteria can pass through the pores of a compact, unbroken soil from a cesspool to a well near it is a matter not fully settled. Since, however, the actual condition of the deeper layers of the soil between cesspool and well can not be known, it becomes imperative to prevent all pollution of the ground-water current supplying wells by either abolishing the cesspools or else placing them at a considerable distance from all sources of water.

Beside typhoid-fever bacteria, those organisms which cause digestive disturbances, and severer troubles, such as diarrhea, dysentery, and possibly other unknown diseases, may be carried into well water. During cholera epidemics, polluted wells might form centers of infection. Eggs of animal parasites may be washed in from the surface. Again, the barnyard manure, representing the mixed excrement of various animals, may under certain conditions be bearers of disease germs, and such excrement should, under no conditions, be looked upon as entirely harmless to human beings.[2]

[2] It is probable that the filth which gets into cow's milk and which appears to be mainly excrement of cows is largely responsible for the severe summer diseases of infants fed on cow's milk.

Besides the protection of the ground-water near the well from pollution emanating from cesspools, etc., the surface of the ground about the well should be kept free from manure, slops, and other waste water; hence the well should not be dug under or close by the house,[3] nor should it be located in the barnyard, where the ground is usually saturated with manure. It should be surrounded by turf, and not by richly manured, cultivated, or irrigated soil. The ground immediately around it should slope gently away from it and be paved if possible. The waste water from the well should not be allowed to soak into the ground, but should be collected in water-tight receptacles or else conducted at least 25 feet away in open or closed channels which are water-tight.

[3] The water may be carried into the kitchen by running the pipe from the well, horizontally, under ground.

CONSTRUCTION OF WELLS.

The well itself must be so constructed that impurities can not get into it from above or from the sides. If water can soak into it after passing through a few feet of soil only, it can not be regarded as secure from pollution. To prevent this, the well may be provided with a water-tight wall built of hard-burned brick and cement down to the water level. The outside surface of this wall should be covered with a thin layer of cement, and clay pounded and puddled in around it. Or, tile may be used to line the well and the joints made water-tight with cement down to the water level. Driven wells, i. e., wells constructed of iron tubing driven into the ground, are, perhaps, the safest where the quantity of water needed is not large and where other conditions are favorable.

These different devices are all designed to keep water near the surface of the soil from percolating into the well. To keep impurities from entering the well directly from the top considerable care is necessary. Such impurities are likely to prove the most dangerous because there is no earth niter to hold them back and destroy them before they can reach the water. Adequate protection above may be provided in several ways. The sides of the tiled wells should project above the surface and be securely covered with a water-tight lid. The ordinary well should also have its sides project above the surface and a water-tight cover of heavy planks provided, which should not be disturbed excepting for repairing or cleansing the well. Under no circumstances should objects be let down into the well to cool. A still better method of protecting the water from above is to have the lining wall of the well end 3 feet below the surface of the ground and to be topped there with a vaulted roof, closed in the center with a removable iron or stone plate. The top should be covered with 12 inches of clay or loam; above this there should be a layer of sand, and lastly a pavement sloping away in all directions.

Too much care can not be bestowed upon the household well. It should be guarded jealously and all means applied to put the water above any suspicion of being impure. This is especially true in dairies where well water is used in cleaning the milk cans, and where steam and boiling water have not yet found their way for this end. Polluted wells in such houses not only endanger the health of the inmates but that of a more or less numerous body of city customers.

In those regions where rain water is the only safe drinking water, the same care is necessary to protect the stored supply from contamination, and no suggestions beyond those already given are necessary here.

CONCLUSION.

In the foregoing pages it has been the aim of the writer to give a few facts and supply a certain number of ideas which, in the mind of any person who has thoroughly understood them and who thinks for himself, may be safely left to ripen into schemes adapted to his own wants and surroundings. How many resources a man armed with correct views may find in the simplest appliances the reader may judge for himself by consulting Chapters IX, X, and XI of Dr. Vivian Poore's very interesting volume on rural hygiene. Whether the means for utilizing household wastes there described and adopted by him would be adequate outside of a limited territory of our own country, I am not prepared to state. For the same reason no definite suggestions can be made in these pages, owing to the wide diversity in the climatic and other conditions obtaining over the vast territory of our country. The writer has, furthermore, omitted all statements of detail which properly belong to the sanitary engineer. The works referred to will, however, supply those more directly interested with the facts and figures desired.

The principles to be kept in the foreground are the disposal of sewage in the superficial layers of the soil in not too great quantity, the disinfection of the stools of the sick with lime before such disposition is made, the digging of wells in places kept permanently in grass and at some distance from barnyards, and, above all, their thorough protection from contamination from the surface and from the soil immediately below the surface.

In every community there are public-spirited citizens who could do much good by taking hold of the simplest and safest methods of disposing of sewage and refuse, putting them into practice, and showing the rest of the community just what good can be accomplished and what harm avoided by a little continuous attention to sanitary matters. In this way many may be led to undertake improvements who, with no definite knowledge of the expense involved and with misgivings as to the final success of the undertaking, would otherwise hesitate to make a beginning.

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