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REPORT.

TO THE STATE BOARD OF HEALTH, ON THE METHODS OF SEWERAGE FOR CITIES AND LARGE VILLAGES, IN THE STATE OF NEW YORK.

BY JAMES T. GARDINER,

Director of the New York State Survey, Chairman of Committee on Drainage, Sewerage and Topography.

The advice of this Board has been so often asked by cities and villages of the State in reference to the proper disposal of their sewage; and the complaints are so numerous of disease and death attendant upon the present ways of treating this matter in most towns; that it has become necessary to determine whether among the many means in use there is any plan of taking away the sewage of towns healthfully, efficiently and cheaply. I say of taking away, because the custom of storing up the filth of towns in privy-vaults and cess-pools, to poison the earth and contaminate the water and air, is one against which all the influence of this Board should be exerted.

The awful lessons taught by epidemic disease are awakening the towns of the State to the need of relief from the prevailing privy-vault and cess-pool nuisances.

What shall be done with the sewage of these many populous towns of New York; how can it be best removed from the dwellings, is the question I have endeavored to answer since the resolution of the Board instructing me to examine, during my recent journey, the results of European experience in sewerage.

I find in general that wherever intelligent efforts have been made to produce proper sanitary conditions for towns, cess-pools and vaults are abolished; and the sewage is removed from the neighborhood of the dwellings by "dry removal," or by "water carriage," which is sewerage.

DRY REMOVAL.

The two common methods of "dry removal" are by the use of the dry earth closet, and the cask, or "pail" system.

In the former the urine and fæces fall into a receptacle, and dry powdered earth is added after every evacuation. This dry earth,

when of the proper kind, both deodorizes and decomposes the fæces so that they disappear. The compost is removed at infrequent intervals and used as manure. The success of this method depends on a proper supply of loam, or clay, dried and powdered, the prompt covering of the fæces after every evacuation, on the removal of the compost and thorough cleansing of the receptacle, and in ventilation of the closet. Without the fulfillment of all these conditions the earth closet soon becomes a nuisance.

In practice it is found that the provision of proper earth, and the constant intelligent surveillance necessary cannot be secured from any but exceptional families. The system of dry earth removal cannot therefore be safely recommended for towns in which so large a proportion of the people are always ignorant and careless.

THE TUB OR PAIL SYSTEM.

The tub, cask or "pail system," used even on a large scale in England, France and Germany, is undoubtedly the best method of removal where towns have neither water supply nor sewerage.

In this system the excreta are allowed to fall into a tub or cask, in England called a "pail," which is removed, emptied, and thoroughly cleaned by the town authorities at least once a week, some disinfectant being placed in the tub after cleaning. In Manchester, England, sifted ashes are added during use to the contents of the tub as a deodorizer.

The simplest form of this method of removal, and the one most applicable to the villages in the State of New York, is that employed in Rochdale, and in Manchester, England.

Rochdale is a city of some 70,000, and Manchester of between 400,000 and 500,000 inhabitants. The higher class of houses are allowed to have water-closets, but four-fifths of the people are obliged to have "pail closets" in their yards built according to plans of the Health Department. Their essential features are: A flag-stone floor raised a few inches above the level of the yard; a hinged seat with a metal rim underneath for directing urine into the pail, which stands on the flag directly beneath the seat; a hinged front and back to the seat so that the pail or tub may be easily taken out and the place cleaned; and a six-inch ventilating pipe from under the seat to above the roof. In Rochdale they use a wooden pail or tub made of half of a disused paraffine cask holding about 100 pounds; in Manchester the "pail" is of galvanized iron and holds ten gallons. Under the direction of the authorities they are removed once a week in covered vans, which bring clean tubs to be put in the place of the full ones taken away. Each tub is covered with a close fitting double lid before removal. The tubs are taken to a depot, where their contents

are deodorized and prepared as manure by mixing with ashes and a small proportion of gypsum to fix the ammonia. Subsequently street sweepings and the refuse of slaughter-houses are added. At Manchester there is by the side of each closet a very simple ash sifter, from which the ashes fall into the tub and help to deodorize its contents. The manure at Rochdale sells for about four-fifths of the cost of its collection and preparation.

In 1873 the net cost to the town of removing and disposing of the house dry refuse and excrement was only about $95 per annum per 1,000 of population; less than ten cents a person per annum.

The system has been in operation more than twelve years. The tubs are removed in the day time without offensive odor. Where ashes are frequently thrown into the tubs at Manchester very little odor is to be perceived in the closets.

For the villages of the State which can have no general water supply, I would unhesitatingly advise the use of the "pail" or tub system as practiced in Manchester, England, as being, from a sanitary point of view, an immense improvement over the death-breeding privyraults in common use. The cheapness of the plan and the smallness of the original outlay of brains and money, in comparison with that needed to build a good sewer system, will make it possible to introduce a tub-privy system into most villages half a century before sewers would meet with any consideration.

At a small cost the existing privy-vaults can be cleaned and filled, and the privies altered into healthful tub-closets. The town authorities must then arrange for the removal of the tubs once a week, and for their thorough cleansing and disinfecting. Any isolated house or group of houses can use the tub system, taking care of it themselves. If the plan is adopted in villages, it will doubtless spread into the country, and become the most powerful means of abolishing the fatal privyvaults which are poisoning the farm wells.

Believing as I do that privy-vaults are such an active and widespread means for breeding disease and bringing needless sorrow and death into hundreds of houses; and being convinced that in this country, as in Europe, the tub system will be found the most immediately practicable, efficient remedy, I recommend to this Board to take measures to secure its adoption in villages and towns where sewers are not likely to be built.

The weakness of the "tub system," as it should be called in this country, is, that the removal, cleansing and disinfecting of the tubs. requires constant care and is a standing expense. Careless, ignorant, or parsimonious village authorities may, by neglect or from false economy, fail to provide for the removal and proper cleaning of the tubs

at sufficiently frequent intervals; but under no circumstances would the evils of this neglect be comparable with those of privy-vaults. The small size of the tubs puts a narrow limit to the interval between removals, and compels attention.

While this system is immeasurably more healthful than privy-vaults, it is unavoidably inferior to that of sewerage, in that it does not provide for the removal of waste-water and slops. In Rochdale and Manchester they have been obliged to build sewers and drains for slops, waste-water and storm-water.

"WATER-CARRIAGE" OR SEWERAGE.

Large villages and towns, where population is so dense as to render the use of wells dangerous, require an abundant supply of pure water distributed through the town in pipes. Means must be provided for the removal of this water after it has been used. Towns with water supply, therefore, find themselves called upon to provide for the removal of excreta, waste-water slops, and storm-water. In Manchester, Rochdale, and other English cities and towns, in Paris and other continental cities, the experiment has been tried of carrying off the human excreta in tubs, while waste-water slops and storm-water are led away in sewers. But the inconvenience, expense, and rigid supervision necessary in the tub system, as applied to large towns, has induced most of the larger cities both in Europe and America to provide for carrying away human excreta with waste-water from the dwellings by drains into the sewers, which already existed for the purposes of draining off more or less of the storm-waters falling on streets and yards. Sewers for disposing of surplus storm-water being necessary in many places, and being already in existence when general water supplies were introduced, it seemed most economical to extend them, and to drain into them both waste-water and human excreta in addition to the storm-water, for which alone they were originally intended. This was the origin of the "combined system" of sewerage, in which the sewers are arranged to carry off excreta, waste-water slops, and storm-water. The large size of these sewers is made necessary by the admission of storm-water.

The great expense of the "combined system" of sewerage, the difficulty of keeping the large sewers clean, and the increasing difficulty of disposing of quantities of diluted sewage have led to the further experiment of building a system of small sewers to carry away only waste-water and human excreta, which are properly sewage; and disposing of storm-water by surface gutters and short sewers leading to the nearest natural water-courses. This is known as the "separate system" of sewerage.

The combined system of sewerage.-This system of sewerage can only be economically used where it is necessary to provide, even at large expense, for carrying off the storm-water underground. The stormwater falling per hour in violent rains over an acre of closely built up city land is nearly fifty times the amount of the waste-water and sewage produced per hour on the same area. The sewage is, therefore, ordinarily a mere trickling thread in the bottom of a sewer large enough to carry off great bodies of storm-water. In time of rain the sewer will be nearly or quite full of dilute sewage, which is absorbed by the bricks, and leaves a coating on them as the water falls. The powerfully flowing stream of storm-water on subsiding deposits silt in the bottom of the sewer which obstructs the flow of sewage, giving it time to decompose. Foul gases are then emitted, and it has been popularly assumed that these gases, called " sewer gas," are the Cause of disease.

Physicians are agreed upon the fact that air from sewers passing into a dwelling is very likely to produce serious disease. That this illness is due to a gas from decomposing sewage is a mere assumption unsupported by proof. But the hypothesis was hastily adopted by engineers, who naturally inferred that the healthfulness of large sewers would be secured if they could only drive out or sufficiently dilute this gas by ventilating the sewer, or prevent its formation by keeping the stream of sewage flowing uninterruptedly. The discussion of the subject by Mr. Elliot Clarke, in the Massachusetts Board of Health report,* and the opinion of other engineers who favor large sewers, seem to be based on this idea.

It is time, therefore, to call attention to the fact that no such gas as "sewer-gas" exists, and that there is absolutely no proof that the diseases which attend the admission of sewer-air into a dwelling are produced by gases. On the contrary the whole tendency of modern investigation is to show that the zymotic diseases are produced by bacteria,t whose germs are developed under favorable conditions. It is well known that the most favorable conditions for the growth of these low organisms are heat, moisture, darkness and the presence of ammonia. The damp walls of sewers present, therefore, all the requirements for a most flourishing growth of bacteria, whose germs may float off on the sewer-air and be carried into dwellings by mechanical action, as dust is borne on any air current.

It is, therefore, most probable that sewer-air brings the germs of disease into dwellings as dust is blown into the window. The foul gases of decomposition may or may not be present. The fatal power over

*Second Report Mass. State Board, New Series, 1880.

The Medical Members of the State Board do not admit or deny that there is such a tendency. It is the author's privilege thus to express his belief. E. H., Secretary.

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