PURE PUBLIC WATER SUPPLIES
At the 1911 annual convention of the Central States Water Works Association, F. B. Leopold, manager of the Pittsburgh Filter Manufacturing Company, read a paper on the address of President Holmes, entitled “Pure Public Water Supplies.” Herewith is the greater part of Mr. Leopold’s discussion of the subject:
The general subject, “Pure Water Supply,” is a broad one and of peculiar interest to me. I shall touch on the various phases of the question as they impress me. The character of waters, sources, natural and artificial, duties of water department officials to the public and benefits to the department, consumer and municipality. With the foregoing brief statement, I beg to submit herewith my contribution to your committee report.
The subject assigned to me as a member of your committee to report on one of the several subjects suggested in your valuable paper of September, 1911, in the form of a more complete study that might be of value or assistance to the water works superintendent or official in the conduct of his work, is one on which much has been written by men far abler to do the subject justice, and to fully discuss would require volumes. My first thought is, that after securing a water supply, or having one, that the highest degree of purity is universally conceded to be not only desirable, but necessary. The next is, what is pure water and how do we get it? The term pure water must be used to a certain extent in a comparative sense, since the quality or degree of purity must vary in different localities. In measuring the purity, we can, of course, start with the ideal, but are limited to attainment by local conditions. The water of ideal purity would be a natural water supply—free from all harmful bacteria, or possibility of harmful contamination, soft, that is free from objectionable mineral matter in solution, clear and sparkling, free from color or odor, cool and pleasant to taste and sight. It is, of course, practically impossible to find a water of this kind in nature in large enough quantities to supply a community of any size. We must, therefore, weigh carefully the advantages and disadvantages of the water that may be available to us, and this must further be considered in connection with the cost of production. The initial investigation covers two phases, quantity and quality. Quantity we must have to properly supply our community; where a normal surface supply is available, this is generally easily determined, and we are immediately up against the question of quality. If surface and underground supply are both available, we immediately have a problem on our hands, requiring the most careful study and the best judgment, to avoid a mistake. We may, on the one hand, have a surface water of fair quality, slight contamination, and fairly clear, as a lake, with quantity assured; on the other hand, a well or underground supply, cool, clear and sparkling, sanitarily pure, but containing considerable mineral impurities in solution; the first, a preferable water for manufacturing and industrial uses, but not desirable for drinking or domestic use; the second, a safe water for domestic consumption, but extremely undesirable for manufacturing. We arc between danger to the health of the community, or health to the industries of the community, which are the reason for its existence often. It is obvious that each is dependent on the other for future growth and prosperity. A condition of this kind must be studied from all phases, and considerable wisdom exercised if a permanent solution is to be accomplishcd. It is by a lack of proper understanding and study of such conditions, that so many cities have wasted millions of dollars in the past, in trying out first one source and then another without proper or intelligent consideration. Often one community may have two available sources of surface supply, then it becomes a matter of comparison, first in character of water, cost of production and probable future conditions of possible sources of contamination either from mill waste or sewage. Among the smaller communities, many arc unable to secure surface supplies at all, but must depend upon underground supplies; there is often as much variation in quality in these as in surface supplies and a thorough exploration of the different probable fields should be made. Waters from underground sources are likely to be better for domestic and drinking purposes than surface waters, although not universally so, but usually have mineral impurities that unfit them to a greater or less degree for industrial purposes, and thus naturally retard a city’s growth; this, of course, more or less seriously depending on other natural advantages to a certain extent.
The fact that I am trying to make plain in the foregoing is, that the securing of the best available natural supply, either surface or sub-surface, is a large problem in many cases and to accomplish it requires care, study, experience and judgment, in any case; if a sub-surface, doubly so.
The next phase after the location of the available supplies and a comparison of their natural purity is, shall we be satisfied with this water or can it be improved, to what extent, and at what cost? Here again we need resource to best study. One water may be purer in its natural state and cost less to purify, but the combined cost of production may be more, or the purified product of one may be preferable to another; here again we must carefully analyze and compare. We may also have to determine the purification to be used to the best advantage, whether filtration, to eliminate suspended matter, color and bacteria, or water softening to eliminate the minerals in solution. We may here inquire whether we really need better water than we have been supplied in past practice, and why. While this question may seem superfluous to the student, it is asked hundreds of times. The answer is obviously “Yes” from every viewpoint. First in the early development of our country, our natural sources, streams, springs and lakes, were comparatively pure, from a sanitary standpoint, our process of manufacturing crude, our population scattered; while the rivers were often muddy, this had no effect on health or on early industries. As we grow more densely populated we discharge greater and greater quantities of sewage and manufacturing refuse in the streams, until at the present time, many of them that only twentylive or thirty years ago were fairly pure are now so badly contaminated that they will not support fish life; still we continue to drink from them. Also our industries have become more varied, processes of manufacture more refined, economics of manufacture more necessary, and our standard of living has also become higher, so that while for every use to which water is put we require a purer and better water we are in most communities being supplied with a liquid as far worse than that we first secured in a public supply, as our requirements are better.
It is the one thing we have just begun to wake up to—the fact that we have been going backwards on, and many people are stiff unable to see that instead of drinking the same water they did years ago, as they so often say, that it is by comparison sewage in many cases. In all cases, for the public’s good, some few must assume leadership, otherwise, we all know, the public only come to a realization of conditions after some terrible calamity has swept over them. If then we start with the premise that pure water supply is desirable, we have first the natural sources:
Surface supplies—rivers, lakes and reservoirs.
Sub-surface supplies—wells, galleries.
Second, after getting the best natural source, the improvement by artificial means, surface supplies by filtration, sub-surface by softening and filtration, think to what an extent we arc justified in purification, the cost and results, and third, whose duty it is to accomplish and how to provide for it.
It seems to me that in many respects the water works superintendent is the most important public official in the community, and he most certainly has the opportunity to make himself so. He is the head of the department most vital both to the industrial and domestic health of the community; he should be, and through him his water board, the best qualified to decide all questions relating to the water question of any community, and to advise the people whom they represent in an intelligent way what action is for their best interest and be the first to advise when action is wise or necessary. In order to do this, the superintendent and water department officials must take a sincere and definite interest in their work, must study all conditions and questions relating thereto. They should carefully investigate their conditions, and compare them with other cities, carefully considering differences in localities. character of water and availability. They should determine where and how improvements might be made in quantity and if necessary in quality and always, if the quality can be improved. study any available methods of so doing; and after exhausting their own resources of investigation and gathering their date together in the shape of definite facts and records; then if satisfied that improvement can be made, caff in consultation expert advice of some engineer of known standing, reputation and experience in the particular field they desire to consider, and place the problem before him to examine without any expression of their views as to how it should be solved. Should he after due consideration coincide with the deductions they may have drawn, they may feel reasonably safe that they are correct; should his conclusions be at variance and his reasoning not be convincing, do not conclude that he is wrong but place your data and conclusions before him for consideration; he may show you where you have gone wrong, or he may find something that has escaped him; if still at variance, and unconvinced, call another man, to make a parallel investigation, but do so without either publishing your former engineer’s or your own conclusions, or to be in any manner influenced; should he follow the opinions of your first man, you can reasonably and safely conclude that you were wrong; on the other hand, should he agree with your conclusions, you might fairly conclude that between the two you were safe in adopting your own ideas. After reaching this point, you arc then in a position to consult with your constituents and advise them, and when you are in an official position that presupposes knowledge of certian duties and conditions you start with a certain amount of public confidence: if then you will equip yourself to deserve it, there is little danger of not being able to increase it. Take the people frankly into your confidence, through the press, if possible; tell them what you have done, give them actual conditions, as they exist, a full report of your investigations, the facts developed, and how the conclusions were arrived at, and the probable results if conditions are not’ rectified.
I believe I have shown in the foregoing whose duty it is to procure the best water for a community, and how it may be assumed, but it must be a self-imposed duty, otherwise it will be everybody’s business. I will now sugest a few hints as to the making of investigation and education of the public to the carrying out of your conclusions, for it is up to them in the end. The first step is to find out what your present water is, this means a series of analyses, not one but as large a number as possible, continuously covering a period of time. Most of our State boards of health in the central States are now equipped with laboratories, and while only a few of them can so far have more than an advisory influence over water questions, practically all are in a position to make analyses and advise on the conditions that should attain in our water supplies; and will gladly do so if called upon, and that without further expense than is entailed in the gathering and shipping of samples; it is. therefore, in the power of the water works superintendent to ascertain definitely and surely just what kind of water he is distributing, and the effects of its use, and that from an authority that will be accepted without question by the people. If the water be a surface water, a bacterial analysis will probably suffice; if a well water, both bacterial and mineral should be made, as the latter affects industrial use. Should a bacterial analysis show the advisability or necessity of purification, then if the present supply is the obvious one to use, there comes up at once the method or manner of so doing. Filtration of some sort in this case is, of course, the natural conclusion, and while to the writer, after twenty years’ experience, there could be but little question, nevertheless there are several so-called methods of filtration, each having to some extent its advocates, and therefore entitled to consideration. These are mechanical, slow sand, and several variations of galleries. Of the first mentioned. there are two types, gravity and pressure. The first mechanical filters were pressure filters, and these are still used to some extent, largely on account of cheapness of first cost, at the present time probably not to exceed ten per cent, of the smaller installations only are of this type in some States; the boards of health have taken a decided stand against their use at all for sanitary work, and in the writer’s opinion deservedly so. The gravity type now in general use are usually constructed of concrete,. except in some of the smaller plants where cheapness in cost is a vital feature; of this type probably ninety per cent, of the plants of to-day are being built There are upwards of 500 mechanical filtration plants in operation in the United States, they are adaptable to any kind of water, and producing the highest bacterial elimination of any type of purification plant, taking up so comparatively small space, are economically operated, and capable of producing if properly designed and constructed, a clear, pure, sparkling water, irresnective of its natural condition. The principal thing is to secure proper design and construction. The slow sand filters are very expensive, require considerable ground area, and only adapted to waters of very low turbidity, although when used on a suitable water, will give very satisfactory results. The efficiencies are not usually as high as the mechanical type, nor the water as clear and sparkling; there are but forty or fifty of these plants in operation in this country. Of the galleries there have been many different varieties installed in the past, all of course depending on a sand and gravel bottom river; some consist of a wooden crib buried in the river bottom from which the water is drawn; others, of a concrete or masonry gallery built in or beside the river so arranged that the water passes through the river sand bottom into the gallery and is pumped therefrom; others of a larger perforated conduit buried in the river bottom; and others again, of a series of perforated or slotted pines connected to a central gathering pipe all buried in the sand; most of these have proven to be simply temporary expedients, and have been largely abandoned.
If the supply must be a well then the mineral analysis will require to be studied, and the effect of the use of the water on the industries of a community considered. The question of softening, and its additional value to the water, determined. Whenever vou convince the public that you are really working to accomplish something for them, and not simply holding down a political job, you are going to make your tinue of office more secure, because the people want that kind of a man just as much as the corporation. only they do not hunt for him, he has to “show them,”