THE VALUE OF PURE WATER

THE VALUE OF PURE WATER

It is the object of this paper to present to you briefly some observations upon the value of a pure water. The subject has been so ably handled recently by George C. Whipple in his two books. “The Value of Pure Waters” and “Typhoid Fever.” that there is little to present in the way of additional statistics, except such as have been obtained in the last four years since these works were published. These data are being constantly supplemented by the numerous statistics of our health departments and sanitary associations, all of which data are available to a large part of the membership of this association. It is believed, however, that a brief review of these matters to date will be of some value. The term “pure water” is herein given its usual significance, as understood by those engaged in the supply of public water. It must be healthful. clear, tasteless, odorless and reasonably soft; the importance of these requisites being roughly in the order stated

The Cost of Water.— It is an impossible task to value a vital necessity. Water is generally considered to be worth its cost in any particular locality. The larger part of the thickly populated area of this country is blessed with an abundant rainfall, and local circumstances such, that Supplies for all purposes can be obtained for moderate expenditures. With the spread in population, regions are now being settled in which the rainfall is less abundant, and these newer communities are cheerfully facing and making expenditures for water that very greatly exceed the necessities in the eastern and central states. Upon the Pacific coast there is no dispute as to the inherent value of a water right, developed or undeveloped. Such values are obvious to the California citizen. According to the United States Census Bureau for the year 1907, the investment in public water supplies in cities of over 30,000 population amounted to $638,000,000, or $32.00 per capita. The approximate value of these properties was estimated at … or $-31.60 per capita. The annual operating expenses of these 105 cities, with 19.6 million of population, supplying 1,010 billion gallons per year, or 142 gallons per capita daily, amounted to $29,000,000, including taxes at 11/3 per cent, on the present value. If we allow 5 per cent, on the present worth as the value to the people of the money invested, and 2 per cent, to cover depreciation, the cost of this water will average $71.50 per million gallons, or $3.68 per capita per year. To the figures named must be added the cost of the improvements on the premises of the consumer, aggregating a very considerable figure, and probably bringing the average cost of water up to $100 per million, or $5 per capita. These figures include all supplies, good and bad, and probably represent, roughly, the average cost of water as it is supplied to-day.

Value of Pure Water. It is the sentiment of the best people in this country to place the value of human life above price, and the public is constantly making expenditures to promote safety, under circumstances where it would be difficult or impossible to show a direct and certain monetary return. Such is not the case with water. Very conservative estimates show that where a pure supply replaces one that is polluted, the monetary return to the community is tremendously in excess of the expenditures necessary to bring about the improvement.

Aesthetic Value—It is well known that where a public water supply is turbid or otherwise objectionable to sight or smell, large expenditures are made by citizens able to afford it for bottled waters. Estimates are presented by Whipple, which seem to indicate that these expenditures are sufficient in many eases to purify the entire public supply. The expenditures for a suitable table water are doubtless considerably augmented under circumstances where supply is publicly believed to be unhealthful, but it is probable that the expenditures for table waters are most largelybrought about by the bad appearance of the public water supply covered by the requisites ot clearness, taste and odor.

Hardness.— Hardness of water in the popular mind is a very general term, the significance of which varies largely with the locality. The eastern waters generally are very soft compared to the waters of the middle west, and the latter aresoft compared to waters of the western piauteau country generally. For drinking purposes most people become quickly acclimated to a hardness of 200 parts per million, and many drinking waters considerably higher in hardness are highly per zed. The ground waters as a general rule, run bout the same in hardness as the low water flow of the rivers, but average possibly 50 per cent, higher. There are in the middle west many beautiful ground waters whose hardness runs into very high figures. As the cities develop, the needs of a soft water in the household and the factory are better appreciated, and while water softening has been practiced in the industries for a considerable time, it is only recently that the municipalities have turned their attention in this direction, and only a a very — few municipal municipal have been built. The financial benefit of a soft water in the household is not difficult to estimate. Experiments and figures by Whipple on the basis of one gallon per capita used for purposes requiring soap, with soap at 5 cents a pound, indicate a value of $10 per million gallons for each 100 parts per million reduction in hardness. There are other household economies brought about by soft water, such as the maintenance of plumbing and heating systems, the saving in the wear of clothing in washing, and in manufacturing cities very considerable economies in steam plants, and the mechanical arts in which water is used. There seems to be no doubt but that the large majority of the water supplied in the middle west could be softened yvith great profit. As water softening is practiced to-day, it is practicable to so construct the municipal filtration plant that the water may be softened without material addition to the plant investment. In such plants, therefore, the question of softening is an operating question and in places where the waters are excessively hard at certain periods of the year only, it is practicable to incur the rather high operating costs only at such times as the softening appears to be of financial benefit. At Columbus, O., for the year 1910, the operating cost of the filtration and softening plant is stated as $19.42 per million gallons, of which probably $12 to $15 represents the cost of softening. This plant reduced the incrustants from 111 to 35, an average reduction of 76 parts per million, and the total hardness from 270 to 85, a reduction of 185 parts per million. Where alkalinity or temporary hardness only is reduced, the cost is much less, thus at New Orleans, for the year 1910, the alkalinity was reduced from 99 to 39 parts per million, with a total operating cost for filtration and softening of $6.60 per million.

Hygienic Value.—It is from the standpoint of health that pure water firings its largest financial return. The most important of the water-borne diseases are Asiatic cholera and typhoid fever.The former has been practically eradicated in the most enlightened communities. Great strides have been made in the reduction of the typhoid death rate, but this disease is still prevalent throughout all civilized communities, and very much remains to be done in America. M. O. Leighton estimates the average value per life taken by typhoid at $4,635; $5,000 is very commonly considered to be the value of a life. There are from 10 to 20 cases of typhoid for each death.

It is very difficult to estimate the cost per case, but statistics available seem to indicate actual expenditures of about $2,200 for each death. Allen Hazen has presented figures on five cities where purification works have been introduced that appear to indicate that for each typhoid death saved, three additional lives have been saved from other causes. The pure water has evidently a very beneficial effect upon diseases diarrhoeal in nature, and probably also engenders an increased vitality that assist’s in the” resistance to other diseases not water-borne. After considering all these figures. Whipple concludes that $10,000 per typhoid death saved is a eonseryative estimate of the saving secured through the purification of a polluted supply. Upon this basis a saving of 10 per 100,000 living is equivalent to $1 per capita per annum (a convenient figure for estimating purposes), and he estimates the value of the purified water at $9.50 per capita per annum at Lawrence, Mass.; $4.75 at Albany, N. Y.; $3.80 at Binghamton, N. Y., and $4.75 at Watertown, N. Y. The filtration works at Cincinnati, placed in operation in 1907, have apparently been effective in reducing the typhoid death rate per 100,000 from 80, 41 and 71, during the three years preceding the starting of the works, to 18, 13, and 6 for the three years following. an average reduction of 52, equivalent to $5.20 per capita. This, on the basis of the present population of 364,000. is equivalent to 1.9 million dollars per annum, which is 6 per cent on $31,000,000. The filter plant and reservoirs cost about one and three-quarter million dollars. At Columbus, O., the saving based on tyvo years following compared yvith three years preceding the beginning of filtration operations, has been about 34 typhoid deaths per 100,000, worth to the citizens of Columbus $3.40 per capita, or $616,000 per annum. This is 6 per cent, upon 10.6 million dollars. The filtration works are reported to have cost about half a million dollars. Other statistics are available that show savings of from $3 to $7 per capita per annum through the benefit of pure water upon health.

Cost pure of Filtration,—The water upon health. cost of filtration has been very generally estimated at $10 per 1,000,000 gallons of yvater filtered, including operation ana fixed charges. In mechanical filtration the operating costs run from $3.50 to $7 per 1,000,000, with fixed charges, including basins, of very nearly the same range. The writer has the figures upon about a dozen modern plants, large and small, that run from $15,000 to $25,000 per 1,000,000 gallons of filter capacity, including basins. The average is about $17,500. Allowing 7 per cent, for fixed charges, the above figures of cost and operating cost produce annual charges of from $7 to $14, with $10 as a mean. This figure corresponds fairly well with estimates upon slow sand filtration plants, in which the principal item of cost lies in the fixed charges. They also handle waters materially different from the turbid waters handled by many of our western mechanical filtration plants. At $10 per million gallons and a consumption of 100 gallons per capita, the total cost of filtration is 36½ per cent, per inhabitant per year, and at 150 gallons per capita, which is nearer the average consumption for cities using river waters, 55 cents per capita per year. Assuming the cost at 55 cents and the value of a life at $10,000. including incidental losses, a saving of five and one-half lives per 100,000 will balance the cost of filtration. A reduction in the death rate of 11 will show a return double the net cost, and in all of the cities whose death rates have been cited above, the indicated net return amounts to from six to twenty times the yearly cost of purification, including fixed charges. Viewed as a business proposition, it can be conservatively stated that where a polluted water is effectively filtered, the net return in lives saved, after deducting operation costs and depreciation, will amount to from 50 to 200 per cent, per annum upon the investment in filtration works. In the light of these figures is there any better municipal investment than pure water?

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