INSPECTIONS OF WATERWORKS

INSPECTIONS OF WATERWORKS

Prof

Why is inspection of watersheds desirable? Let it be assumed that the water supply, whose quality is to be maintained or improved, is what is known as a surface water—that is, is obtained from small streams, lakes, or rivers, the water in which comes chiefly over the surface of the ground at the time of rainfall. Such surface waters do not exclude spring water, but let us assume that the surface water is the main supply of such streams.

It may be that the storage capacity in the basin is so large that the volume of water added in any particular rain is inconsiderable and affects but little the quality of the water already stored, or the water may be taken directly into the supply pipe from some small stream without any considerable storage.

There are, then, really two classes of surface waters—one, in which the supply is taken directly from a stream, the quality of which is immediately affected by any rain; the other, where the water comes from a lake or through some large artificial reservoir, the waters of which are not affected by rain unless the latter be of long duration. In this case, an inspection of the watershed is much less necessary than in the former case, although in this state it is the lake supplies, as in the cities of Auburn and Syracuse, where the inspection of watersheds is assiduously practiced. It is in the former case, however, that the greatest danger exists, since, without any period of settlement, the accumulated pollution of the sur face wash is carried directly into the water pipes.

It would, of course, not be justifiable to say that the water from a lake like Owasco Lake would be so purified by its period of settlement that an inspection of the watershed would be useless, and yet, it is well known that in a reservoir large enough to hold two or three weeks’ supply, the greater portion of the disease germs in the entering water will have perished and disappeared before the water is taken out at the other end of the reservoir. Apparently all the germs do not die, and probably some of the more hardy, perhaps only about 1 per cent, of the total number, may live on for months or even years, so that there is always a small possibility of the progress of such germs through even the largest reservoirs. Then, again, the internal currents of water in such a reservoir act (at certain times of the year) to bring up to the surface accumulated sediment which may restore to the water certain germs, which had, up to that time, been held at the bottom. In spite of these possibilities, however, there is no question but that a larger reservoir is a very important factor in the elimination of pollution from an unprotected watershed.

The typhoid death rate in New York City (about twenty per 100,000 per annum), is a good example of the way in which, through the agency of large reservoirs, the pollution on the Croton watershed is eliminated. On the other hand, when a reservoir is small, freshets carry the pollution of surface wash rapidly through the reservoir and the settle ment will not be sufficient, and the effect of the pollution is to be seen in such epidemics as have occurred at Plymouth, Pa.: New Haven, Conti.; York. Pa.; Scranton. Pa., and other places.

Where no impounding reservoir exists, then the necessity for careful inspection and super vision of the watershed, which is washed by the falling rain so that whatever debris is found on the ground is carried into the nearest watercourse, is, by that very fact, made much more important. This can be realized by standing at the edge of a barnyard and watching the rain falling first on the roof of the barn, then in larger quantities from the eaves onto the manure pile into the yard be low. then accumulating in pools of reddish black, concentrated liquid, until the volume is sufficient to form small rills which gradually assemble into a fair-sized stream. Similarly, the pig-pen drainage is washed out from under or even through the building, and. after com billing with the barnyard drain, is carried into the stream nearby. The very idea of drinking such filth is nauseating in the extreme, and in many cases newspaper reporters of the yellow type have fairly revelled, their attention once directed to the matter, in the particulars of sensational description and of elaborate details. It is common for small slaughter-houses to be built on the side of streams so that the offal, carrion and refuse of the place may be carried off without effort on the part of the owner, and there are a number of such places in this state where brooks, used as places of deposit for slaughter-house refuse, discharge directly into waterworks reservoirs.

But this sort of animal refuse is not the most serious pollution. The leechings and washings from privies and cesspools, carrying, as they do, germs of contagious diseases, are most to be dreaded, and when a privy (with no vault underneath) is built on the side of a steep ravine and is so located that the natural drainage of the side hill on which it is built cannot help but run around and through and under the building, then the pollution of the stream in the gulley is not only direct and inevitable, but the character of the pollution is of a deadly sort. Fortunately, the germs thus carried into the stream suffer the vicissitudes of all life exposed to the attacks of hostile forces.

At the time of freshets the streams carry mud in abundance, which mud is continually settling out of the water as opportunity offers, and with this settlement of mud there occurs also the settlement of the germs. Also the pathogenic or disease-producing germs are usually weaker and more susceptible than the putrefactive and other organisms which are found in the water in great abundance after any rain storm, and which tend to inhibit or destroy the pathogenic germs. But some will survive, and. with favoring conditions, will reach the water intake and distribute themselves through the water supplied by the city and may result in an epidemic.

Any inspection of the watershed, therefore, should look to the elimination of the dangers above described and to the location of barns and barnyards, pig-pens and poultry yards, privies and cesspools, so that no direct drainage into the stream shall be possible.

It is out of the question for any surface water supply to be pure, since the mere fact of the passage of water over the soil inevitably results in the collection of organic matter; and it is no exaggeration to say that the time will inevitably come in this country, as it has already in Germany, when no surface supply will be considered satisfactory unless the water is filtered. The only alternative will be water gathered from areas which are owned by the water company and on which, therefore. all dwellings may be prohibited, all cultivated land avoided, and where the primeval forest may be restored, making the watershed equal to that from which forest streams emerge. But at present, when the public mind is not awakened to the dangers inherent in surface water and when the public purse is not opened sufficiently to pay for the necessary filtration plant, much may be accomplished by an inspector of the watershed, and, while, probably, it will not be possible to entirely eliminate the dangers of surface pollution. undoubtedly much may be done. Certainly any direct drainage into the streams may be cut out, and the drainage from barnyards in the immediate vicinity of the intake may be avoided. Just what percentage of pollution may be eliminated in this way it is impossible to say, but the very fact that an official of the water company is on duty and authorized to punish infraction of water rules, acts as a most valuable deterrent in the case of those whose own conscience is dormant in this matter.

In carrying out any pre-arranged programme for the inspection of a watershed with a view to eliminating surface pollution, constant attendance and effort is necessary, and this may be cited as the main principle of the effort. It is not sufficient, for instance, as is done by some municipalities of the state, to send the health officer to drive over the watershed once a year in the hope that casual inspection from the seat of the carriage will allow him to determine what pollution occurs. For an inspection to be efficient, each portion of the watershed should be visited at least once each week, and the number of inspectors and the time required will depend on the area of the watershed and on the density of population. A small gathering ground, as, for example, for the village of Croton, where the water supply comes from springs and small streams, the whole watershed being probably not more than twenty-five acres, and where no dwellings are in the vicinity, requires a visit of an inspector once a week, and it would take him only a few hours to patrol the banks of all the streams involved.

On the other hand, the watershed supplying Auburn covers nearly two hundred square miles, with innumerable gullies and with large areas far removed from highways, so that any efficient inspection involves several inspectors and their constant attendance. And in the case of lakes like Skaneateles Lake, Canadaigua Lake or Conesus Lake, where there are a number of cottages directly on the shores, no efficient inspection can exist unless these cottages are patrolled regularly and daily, and this more for the moral effect of the inspection than for the probable interference with any flagrant act of pollution at the time of its committal.

So far as the particular offense to be looked after by the inspector goes, the practice of discharging sewage is perhaps the most important. To determine any possible location, the inspector must satisfy himself as to the point of discharge of the sewer of every house on the watershed, and this must be done personally. without apparently reflecting on the statements of the owner of the house. If any such sewers are found, the pipes should be cut off and the sewage either turned into some other watershed, or spread out over the ground away from the stream, or purified by some artificial treatment before discharge.

The next point to be noted is the presence and location of privies. These nuisances should be moved as far back from the banks of the streams as possible, although it is really impossible to eliminate all danger by such removal since the surface of the ground always slopes toward some stream and pollution may be carried for considerable distances over or through the soil. Watertight boxes ought always to be provided so that no possible pollution of the surface wash can occur and then periodically the contents of these ought to be hauled away and buried, so that the privy loses its dangerous character. The city of Syracuse has installed on the watershed of Skaneateles Lake a most admirable system of collection of privy wastes well worth inspection by those whose duties involve similar practices on other watersheds.

Cesspools, in general, are not dangerous if they are located 50 feet or more from the stream and if no overflow occurs.

Barnyards ought not to drain directly into streams, and the inspector will note the possibilities of removing such drainage. But when, as in so many cases, the stream flow through the barnyard, the only remedy is to move either the stream or the barnyard, and usually the latter is the easier of accomplishment. In the course of an investigation made by the department there was found a stable built over a stream so that the farmer could shovel manure through a trap-door in the floor into the stream at a minimum of expense and labor, but regardless of the effect on the stream. The Waterworks Company, of Ithaca, moved a number of barns back from the edges of streams and laid many hundreds of feet of tile drain on the lower edge of barnyards in order to protect the watershed, years before the famous Ithaca epidemic of typhoid fever occurred, and no more glaring truth has ever been more conclusively demonstrated than by this epidemic, namely, that careful, intelligent and constant watchfulness is essential, year after year, if the waters of a stream are to be made in any way fit for drinking; and even then the generous support of the law, of public opinion and of the water company to supply funds for necessary changes must be provided.

Preparatory to installing the enlarged water and filtration system in Saginaw, Mich., the city will be supplied with water from the re-inforced east station and the west side station abandoned.

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