The Disposal of Sewage.
There are in use some three practical methods of sewage disposal adapted to the average country residence where no public sewers exist. None of these three systems are perfect ; in fact, none have proven entirely satisfactory, when, after a lapse of years, a minute investigation of their operations has taken place. The adaptation of any of these systems is limited somewhat to conditions, much depending upon the character of the surrounding soil, and, at times, upon the elevation of the premises, so that no one system can be specified to meet all conditions.
The first system, if system it may be called, and one which is largely in use to-day all over this country, is to dig a big hole in the earth, wall it up like a well with stone laid loosely, the top arched over and sodded, and into this the house drainage is carried, relying upon a porous soil to absorb the liquids, while the solids lodging in the shelving rock interstices are broken up and ultimately soak away into the ground, “ out of sight, out of mind.” If a cesspool of this character can be located from 200 to 500 feet away from any residence, if no danger of contaminating a water supply exists, and the cesspool top is below the level of the cellar bottom of the residence, and the character of the soil is loose, it may perhaps do no damage, and answer the purpose for several years before it finally chokes up and the drain leading to it becomes full of solids. Then it is time, if not before, to dig a new cesspool.
A slight improvement on the single cesspool is the double cesspool system, the first of these being below ground, walled up and cemented water tight, the second excavated and walled up with stone loosely laid ; the house drain is then carried into the first at a point near the top, while an overflow is provided from the first to the second, this overflow pipe being carried down into the first cesspool to a point near the bottom, thereby forming a dam, which prevents most of the solids entering the second cesspool, but allows the liquids to overflow freely and soak away into the soil surrounding the second cesspool. This is sometimes called the twin cesspool system, and is much better than the single cesspool ; the solids being retained, the man-hole cover can be removed and the fœcal matter excavated and sent to the compost heap. The adaptation of this manner of cesspool also requires a loose, dry soil or one that is under-drained, yet a great danger exists of water-supply contamination.
The second system which may be considered is that of Surface Irrigation, and can only be adopted when there is a large area of ground of character and location favorable. The space used for the reception of this system should be from one-eighth acre to one acre, and located from two to five hundred feet distant from any residence, and from ten to fifteen feet lower than the foundations of the premises discharging upon it. It consists, first, of a watertight storage tank made of brick, wrought or cast iron, or perchance stone, and of capacity sufficient to store the entire waste disposal for a day, figuring on a fifty gallon per day per capita consumption. This storage tank may be situated near the house, with closed and sealed top, the drain pipe conducted into it, and once a day emptied by a lever-handled gate valve which can be pulled wide open. The discharge pipe connecting with this gate valve terminates at the drainage field, which should be slightly sloping. At the point where this pipe discharges it is carried along the upper side of the drainage field with small branch outlets taken from the discharge pipe in such a manner as to distribute the sewage over a large area, which territory may be under cultivation as a special garden spot. Almost a complete disintegration of the solids takes place in transit, and the distribution taking place daily before decomposition occurs to any great extent, there is no appreciable offense to the nostril or eye. The writer has used this system with considerable success in the plumbing of country residences. With this system there is little or no danger of the contamination of a water vein which may act as water supply to surrounding territory, as the rapid evaporation which ensues on exposure to the sun, together with the oxidation of the gases produced by contact with the atmosphere, renders them comparatively harmless. Loose loam or sandy soil is a favorable condition in all of the systems under consideration.
The third system entitled to consideration as adapted to a country residence is called Sub-Surface Irrigation, the name in a measure explaining its function. It consists of a method of distributing the sewage by intermittent discharge of a flush tank through a system of pipes laid just under the surface of ground, i. e., from 8 to 12 inches, through a series of perforated pipes, or pipes laid in a disjointed manner, with from three-eighths to one inch of space between each length of pipe, and said space covered by loose collars of same radius as pipe. These pipes are spread out like a fan underneath the ground, laid from five to ten feet apart and substantially level, and are fed from a common pipe coming from the flush tank, which is arranged to discharge automatically or by the opening of a valve. When the discharge occurs this sub-system of piping is theoretically filled with sewage, which finds its way through the fissures before mentioned. The toilet paper and grease in the household wastes are serious detriments to this system, clogging the pipe interstices, and in many instances after a few years’ use the entire system of drain pipes has to be dug up, cleaned and relaid. This system was used in many parts of England and the European continent for a number of years past by Mr. Roger Field, and was introduced in America by Mr. Geo. E. Waring, and is called here the Field-Waring system. This system is not patented, and is open to all who wish to employ it, although many of the devices adapted to the flush tank are patented.
In addition to the above it should be mentioned that a system of Sewage Filtration was experimented on by Mr. Scott West, a New York architect, and while his system was adapted to cities on a large scale, and is in use at present in some large Southern towns, he has never been successful in adapting a system of filtration to the wants of the suburban resident on a small scale. Chemical precipitation is too expensive and requires too much attention for the suburban resident to bother with.
After a brief consideration, therefore, of the methods of sewage disposal, providing there are no public sewers, it must resolve itself into a consideration of—
- The single or the twin cesspool.
- Surface irrigation.
- Sub-surface irrigation.
A decision cannot be made as to the one best adapted without a knowledge of the conditions governing the case ; therefore, assuming that the best adapted system will be approved for the sewage disposal of the particular house in question after a thorough consideration of relative merits, let us proceed with the plumbing of the residence and the further problems of selecting materials therefor.
Cast Iron Pipe for Drainage Purposes.
This pipe has been used for twenty years or more almost universally and with almost perfect success, the only objection being that there is an occasional sand hole in a casting, which, however, is always discovered when a pressure test is employed. The commercial standard is known as “extra heavy,” and no other should be used. One more objection to cast iron pipe is urged by some, claiming that the necessary lead-caulked joints are not scientifically made, and that they are liable to be blown loose when the hubs are expanded by heat from escaping steam, which sometimes happens, more especially in our city buildings. These two points, then, are made against cast iron pipe, viz., sand holes and liability to leakage caused by expansion of lead-caulked joints subjected to steam. In our particular country house we propose to test the cast iron soil and drain pipe to see if there are any sand holes, or perhaps pay the manufacturer an additional percentage to test it before he delivers it, and then we will plug up all the outlets and fill it with water to test our caulk joints and look for other leaks ; so that this can hardly be an objection in our particular case. As for steam, there will be none connected with the drainage of our house.
