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ably there are not many streets in New York the whole of whose flow could be carried to the river through the gutters without at times causing inconvenience at the crossings of the avenues, and, occasionally, overflowing the sidewalks. It would be necessary, therefore, at points where during ordinary heavy rains the gutter flow would become too great, to provide for its removal below the surface. At such points there should begin under-ground conduits of sufficient size, leading directly to the shore and delivering, as by the present proposed extensions of the sewers, at the heads of the piers. These under-ground conduits may be constructed in the form of deep cast-iron gutters covered with suitable strong gratings, the inner edge of the gutter being carried up to the height of the sidewalk; an increase, as the accumulated flow requires it, to be furnished by making these gutters deeper rather than
vided for, by the bridging that is universal in towns which have no sewers, and if the difficulty from ice under such circumstances should prove too serious, the storm-water removal could be effected by the laying of suitable pipes or small sewers at both sides of the streets, only so far below the surface of the ground as may be necessary to prevent freezing. Those who have observed the condition of the gutters, street crossings, and catch-basins during the past winter must recognize the fact that the present system has been as complete a failure as any other could possibly be, and that as much labor has been expended in cutting out the ice of the gutters as would be necessary to keep them and the street crossings free by a lifting of the gratings, and the chopping of channels in the ice. The problem is not a simple one, but the sanitary result to be secured is well worth any effort that its solution may cost. When all sides of the question are examined, it must be seen that it is not a satisfactory solution, either in the matter of storm-water removal or of foul sewerage, simply to get the flow out of sight, and so out of mind. Whether in sight or out of sight, the water of the rainfall and the filth of the sewerage are most serious elements of a problem of the gravest character. There is no safety in the treatment of either short of absolute control from the moment of their production to the moment of their final and satisfactory disposal.
It is understood, as a matter of course, that these surface-water channels are intended for the removal of water only, or of water with the smallest possible addition of organic matter. The cleaning of the streets of a city like New York by washing its surface filth into adjacent water-courses, has nothing save momentary economy in its favor, and it has everything against it. By the system proposed, the following most important results will be secured:
1. The complete and immediate removal of all rain-fall from the streets, from the house-roofs, and from the interior of the blocks.
2. The drainage of the subsoil to the depth of the present sewers, and the withholding from the soil of all of that volume of foul water, from streets and from housedrains, with which it is now contaminated.
3. The retention below the pavement of the dirt which is now churned up through it to add to the foulness of the streets; the washing of the surface, and especially of the gutters, by every rain that falls, and a very
great cheapening and facilitating of the important work of street-cleaning.
In this arrangement, no provision has been made for the removal of the wastes of houses, manufacturing establishments, stables, etc., the foul sewerage of the population and of its industries. This branch of the subject should be treated quite independently of the removal of storm and subsoil water. It is the material so to be treated which constitutes the chief dangerous element of all town sewerage; it is this, mainly, which leads to the contamination of the soil; it is this, largely, that gives the character to the deposits in sewers that makes the gaseous products of their decomposition so dangerous; it is the means by which this is carried to the sewers that now conveys sewer-gas to our houses; it is the material thus added to the sewerage of the city which makes it especially difficult to deal with, and dangerous in its final disposal.
In short, it is this addition to the drainage of a city which makes the whole sewerage question so difficult. There is no safety, and there can be none, in the means for its treatment which are in almost universal use the world over. The simplest requirements of the public health make it imperatively necessary that a radical change of method be adopted.
In this part of the work everything must, perforce, be begun anew and carried out independently and completely to the point of remote and safe disposal. The organic wastes of human life being entirely eliminated, the drainage of roofs and back yards, of a clean soil, and of tightly paved and well-swept streets, is robbed of its dangers, and the resultant outflow may be discharged at the pier-heads without present or future danger. The works suggested above for the accomplishment of this end could have in no wise a detrimental effect on the sanitary condition of the city. While it is a simple matter to suggest this elimination, there are some practical details of the work which cannot be finally determined nor adequately discussed in the preparation of a magazine article. Certain leading principles, however, can be set forth, and an indication of processes can be given, which will afford a sufficient basis for study and experiment.
The system of sewerage, or "pipe-drainage," devised for, and completely carried out in, the city of Memphis is, I am confident, better suited to the purposes in view than any other similar work thus far done. The leading principles of that system are: the restriction of the sizes of the sewers to a capacity
barely sufficient to carry the greatest flow of the day when running half-full; the most complete and thorough ventilation of every part of the sewer; and its thorough washing from end to end at least once in twenty-four hours, by a suddenly discharged volume of clean water sufficient to carry forward, at least to a point where the constant flow is sufficient to keep them in motion, all solid substances delivered to the sewer by its tributary house-drains, so that nothing of a putrescible character shall remain in the sewer long enough for its decomposition even to begin. In Memphis, the most distant part of the system is about two and one-half miles from the outlet of the main sewer. The sewerage delivered at this point is discharged into the river within less than an hour and a half from the time of its entrance into the public drain. Such matters as may be left stranded near the upper end of the sewer are, by its flush-tank, washed into the constant flow at least once a day. Every connection with the sewer acts as a copious ventilator for it, and fresh air inlets of sufficient frequency supplement the action of these ventilators, effecting a constant renewal of the atmosphere it contains. As a result, what is known as sewer-gas exists nowhere within the whole system of sewers. There may be detected, now and then, during inspections of the work, a fresh fœcal odor, or the odor of foul-smelling chemicals passing through the drain, but nothing that suggests decomposition, nothing at all comparable with the atmosphere of the very cleanest of the sewers of New York.
The capacity of small pipes for removing sewerage is very much greater than those would suppose who are familiar only with the large works generally constructed. The sewerage of Lenox, Mass., constructed in 1876, is composed entirely of vitrified pipes six inches in diameter. These deliver the sewerage of the whole village, and remove it to a distant point, and have done so in the most complete manner since they were first laid. These sewers have no flush-tanks, and are, therefore, less completely cleansed than they should be, though no complaint is made of their condition. In the village of Cumberland Mills, Maine, a considerable manufacturing population has its waste matters entirely removed by six-inch pipes, flushed by tanks which are fed with the sewerage of the houses near the heads of the lines.
A six-inch pipe laid with a fall of one foot in three hundred feet, and running but halffull at the time of greatest use, will remove
the sewerage of two hundred and fifty average houses, with a consumption of thirty-three and one-third gallons per head per day. Therefore, a six-inch pipe, having a fall of less than twenty feet from the Fifth Avenue to the Hudson River, would remove completely all of the household waste of all the houses on one side of the street for the whole distance, without being at any time more than half filled,-supposing the consumption of water to be restricted to one hundred gallons per day for each three persons of the population. As the present rate of consumption is very much more than this, the lower portion of a sewer laid on such an inclination would have to be proportionately increased; and in view of the considerable consumption of water in hotels and manufacturing establishments which may in future be constructed on any street, further provision would have to be made for their greater discharge. Full allowance being made for all contingencies, sewers of relatively very small size would be ample for all future needs. And not only ample, and therefore advisable on the score of economy, but really very much better than larger sewers, for the reason that a more perfect sanitary result is secured by the more complete flushing of a small sewer by the discharge of a flush-tank of a given size, or by the flow of a given stream, and the more complete ventilation which given means effect in the case of a limited volume of air.
The flush-tank referred to is the invention of Rogers Field, Esq., an eminent civil engineer of England. It has no moving parts, is absolutely automatic in its operation, and is so constructed that, by however small a stream it may be filled, when once filled the continued flow of that stream causes it to discharge its contents at once and with great rapidity. The flush-tanks in Memphis, of which about one hundred and thirty are in use, discharge about one hundred and twelve gallons in from thirty-five to forty
sidewalk for engine vaults, for storage purposes, or for any other use desired, and so that access to it might be made by removing the gutter only, without breaking up the permanent covering of the street. As adequate provision is already furnished for the drainage of cellars, a prohibition— important for other reasons-against the location of water-closets, sinks, etc., below the level of the basement floor, the same being not lower than four feet below the level of the gutter, would enable ample fall for the whole house-drainage to be afforded by placing the sewers six feet below the level of the gutters. Opposite each house lot, and for safety's sake even more frequently, the sewers should be provided with branch pieces to receive the house-drainage, and, for permanent security and the insuring of a tight joint when the connection is made, these pieces should be of heavy cast-iron, so that the extension of each soil-pipe may be firmly leaded to the sewer, making an absolutely tight connection without breaking up the street, or interfering in any way with the main construction. Probably it would be best, all things considered, to make the whole sewer of cast-iron, for protection against injury during the construction of public or private works. The diagram on the following page shows the location of the present sewer and of the proposed sewer; the construction of a block pavement laid in gravel and jointed with asphalt; the stormwater gutter with its grating; and the connection of the house-drainage with the new sewer; as also of its roof and yard water and subsoil with the old sewer.
In the application of this system to the sewerage of that part of New York City which is regularly laid out, a separate housesewer should be laid at each side of the street, with branches at the ends of the blocks (on the avenues), according to the direction of the slope. A flush-tank should be placed at the head of each sewer and of each branch in the avenues. The sewer should be laid at the edge of the sidewalk, under the gutter, so that it would not interfere with the use of the space under the
The foul sewerage of the city being thus led to the river front, or to other suitable points, the serious question of disposal remains to be considered. It is hardly necessary to offer arguments in opposition to the present practice of delivering this sewerage into the tide water which is constantly flowing back and forth in front of the city, to be ultimately deposited along the populous shores of the rivers or bay, to be exhaled from the surface of the water, or to settle on the mud flats of Buttermilk Channel, Gowanus Bay, Prince's Bay, or elsewhere. Notwithstanding the provision made for the exclusion of all surface and storm water from this sewerage, its volume will still be enormous,-nearly equal to the whole water supply of the city, which is now about one hundred million gallons per day.
The first idea that suggests itself to all who consider such questions is that, in the
water of the Atlantic Ocean at a point off some unoccupied portion of the south shore of Long Island, were this possible, would be entirely satisfactory. Their disposal in wide surface irrigation on the sandy land of the Long Island coast would secure such purification that the effluent might flow off from the shore without offense or danger. The area required for this purpose would be large, and the operation would be costly; but some form of disposal which shall secure the purification of the harbor is sure to become in time, if indeed it is not now, a commanding necessity. Whatever the system adopted, and whatever the means of purification, it is already manifest that proper disposal of the entire sewerage, not only of New York but equally of Brooklyn, cannot be too early taken into serious consideration.
interest of the people, the immense amount of fertilizing matter contained in the offscourings of such a population as that of New York, should be turned to profitable account. Experiments in this direction have been made and are being made at London, Berlin, Paris, Dantzic, and elsewhere. Thus far, all that has been proven in its favor is that it offers a good means for the purification of the effluent. The hope of profit, or, indeed, of any important return for the cost of the work, has apparently been abandoned. Possibly at some future time a change of the agricultural conditions of the country may enable us to realize this theoretical profit. At present the only aim that can be pursued with the hope of success is the purification or the inoffensive disposal of the effluent matters. Their discharge into the deep
To secure a sufficiently rapid flow and to prevent the deposit of sediment in the mainoutlet sewer proposed, which, on such a level line, must necessarily be of iron, and which must work under a head, it will be
necessary to resort to artificial pumping, either directly into the mains or into standpipes. Considering the long, level shoreline of the city at which most of the lateral sewers must deliver, and the desirability of a sufficient fall in the collecting sewers to render them entirely self-cleansing, the best course would be to establish pumping stations at intervals near both shores, and at low points in the interior, from which the outflow of the collecting sewers should be forced into the great outlet main or into a stand-pipe communicating with it.
The above sketch (and it is intended as a sketch only) of a system of drainage covers every element of the problem that need engage the attention of the sanitarian or the engineer. It secures the complete removal of all household and manufacturing
wastes by an independent system of sewers in which the production of sewer-gas will be impossible; the complete removal of roof and yard water; the equally complete removal of street wash; the drainage of the subsoil and of cellars; the prevention of so much of the street dirt as is due to the working up of the soil in which the present pavements are bedded; and the complete protection of the ground under the streets against infiltration from above; and it suggests an adequate means for ultimate removal. The details by which the sketch is to be filled out can be determined only after careful consideration, checked and corrected by actual experiment. That the system is an entirely sound one, so far as the improvement of the public health is concerned, cannot be questioned. That it is entirely practicable will, it is believed, be shown by study and experiment. That it or its equiv-hibitory penalty. As there is a disposition
force the universal adoption of self-closing faucets. Mr. Shedd says that, with the water pressure at Providence, a single kitchen faucet left open for twenty-four hours delivers 22,000 gallons of water, and a 'constant flow as large as a pipe-stem under the usual pressure of New York City will deliver more than the necessary liberal consumption of any family. To make the meter system effective, and to impose a penalty on waste, a graduated scale of charges might with advantage be adopted. For example: for the first twenty gallons per day used for each member of the household, let there be no charge; for the next ten gallons make a limited charge, doubling this for each succeeding ten gallons, so that the carelessness which now leads to the wasting of at least fifty gallons per day for each member of the population shall bring its pro
alent must, sooner or later, be carried into effect, is a foregone conclusion. Being carried into effect, the only remaining grave fault, so far as the site of the city is concerned, would be the contamination of the soil due to causes now in operation. The causes being removed, this would rapidly cure itself under the constant influence of oxidation and of the infiltration of rainwater, and the site of the city would become, in all its integral parts, as completely healthful as its location and surroundings indicate that it should be.
Much consideration is now being given to the question of water supply, and schemes are on foot looking to the introduction of new floods, brought at enormous expense from great distances. That this may in time become necessary is probably true; that it is the best means of present relief may well be doubted. The population of the city is now supplied with water at the rate of eighty gallons per day per capita. But a comparatively small proportion of this supply is used; the remainder is wasted. The tendency to waste increases, and will increase, perhaps, nearly in proportion to the increase of supply. A more abundant provision brought to the city implies a renewal or a supplementing of much of the present apparatus for distribution, and no man can tell where the work and the cost will end. It is worthy of consideration whether or not relief, for at least another generation, may be secured by the very simple process of preventing the waste of what we now have. To this end, it would be necessary to measure the quantity used in each house by meter, and to en
to allow water to run in summer to secure a cool draught, and in winter to prevent the freezing of pipes, the gauging should be taken monthly rather than yearly.
Aside from the very great cost of enlarging the system of distribution-pipes within the city to make available the more abundant supply that is being clamored for, the procuring of that supply involves for works now in contemplation an outlay of about sixteen million five hundred thousand dollars. The relief thereby afforded can, at best, be only temporary. A few decades of growth, and a little further cultivation of the present wasteful tendency, will prove the added supply to be inadequate, and the city will be brought face to face with a problem more serious than the one which now confronts it, and with a still greater disinclination among its people to submit to wholesome restrictions.
It has recently been stated that householders could not bear, and the city could not afford, the outlay necessary to provide every house with a water-meter, to substitute self-closing faucets at every tap, and to protect all supply-pipes against frost. This would, undoubtedly, be a serious matter; but so is the expenditure of sixteen million five hundred thousand dollars and the reconstruction of the interior-distribution system a serious matter. On the first of July last, there were ninety-one thousand three hundred and seventy-five houses in the city; the expenditure of sixteen million five hundred thousand dollars would impose an average charge on those houses of about one hundred and eighty dollars each, with