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RURAL WATER-SUPPLIES *

EDWARD BARTOW, PH.D.
Director State Water Survey, University of Illinois
URBANA, ILL.

The Census Bureau, for the purpose of discussion, has defined urban population as that residing in cities and other incorporated places of 2,500 or more, and rural population as that residing outside of such incorporated places. The urban territory of the state of Illinois in 1910 contained 3,476,929 inhabitants, or 61 per cent. of the total population, while 2,161,662, or 38.3 per cent., lived in rural territory. Only six cities containing more than 2,500 inhabitants having a combined population of 20,000, are not supplied by general water-supplies. Of the cities containing less than 2,500 inhabitants, eighty-five have no general water-supplies, and hence must rely on wells or cisterns for their drinking waters. Many people in cities having general watersupplies, either from necessity or preference, use shallow well water for drinking purposes. Oftentimes the city mains are not extended to new sections. Oftentimes in old sections the houses are not connected with the mains, making the use of a shallow well necessary. Oftentimes the city water furnished has unpleasant physical characteristics, like taste, color or turbidity, causing people to prefer the clear shallow well water. We estimate that the number of people in cities using well water would be approximately the same as the number of people in the rural territory who are supplied by general supplies. It would be reasonable, therefore, to estimate that a population equivalent to the rural population, or that 40 per cent. of the population of the state of Illinois, obtain their drinking water from wells.

In a great measure the relative use of shallow wells in different sections of the state is dependent on the source and character of the municipal water-supplies. In the northern part of the state of Illinois the majority of the city water-supplies are obtained from deep rock wells. In the east central portion of the state the water-supplies are obtained from deep drift wells. In these sections it is a comparatively easy matter to obtain a satisfactory general water-supply, and therefore the number of shallow wells are reduced to a minimum. In the west central and southern parts of the state the general water-supplies are obtained from streams. This method of obtain

* Read at the Sixty-Third Annual Meeting of the Illinois State Medical Society, at Peoria, May 22, 1913, Section on Public Health and Hygiene.

1. Thirteenth Census of the United States, 1910.

ing a water-supply is more expensive than the deep well method, since it requires the building of a dam and an impounding reservoir and in most cases the construction of a filter plant. For this reason 32 per cent. of the cities of more than 1,000 inhabitants in the southern part of the state have no general water-supply. It is possible to have deep rock wells in the northern part of

the state because the St. Peter and Potsdam sandstones, which outcrop in the central and northern part of Wisconsin, dip to the southward, so that they are from a few hundred to two thousand feet below the surface in the northern third of

Illinois, or rather north of a line drawn from Quincy to Chicago. Because the height above sea level in Illinois is less than in Wisconsin, wells which enter these two strata are free-flowing or can be easily pumped. Such wells furnish an ideal water for a municipal water-supply, and in many cases when the expense is not prohibitive, are used as a source of supply for the individual farms. As the water lies in the water-bearing stratum it is absolutely free from contamination. It is only necessary to take proper measures to prevent contamination during delivery to the consumer. Such contamination may occur from defective casing, contaminated reservoir or from faulty connections with impure river supplies.

In the rock wells along or south of a line drawn from Quincy to Chicago there is a strong probability that the water will be very highly mineralized. It is, therefore, necessary in the central and southern parts of the state to obtain water-supplies from sources other than deep wells in rock. In the eastern part of the central area the glacial drift is deep enough and contains gravel coarse enough to furnish a satisfactory water-bearing stratum. We, therefore, find many of the cities in this area obtaining their watersupplies from wells from 100 to 200 feet in depth. These waters are also perfectly free from contamination in the water-bearing strata, and if properly cared for furnish a perfectly hygienic supply. Many farms in this area obtain at a comparatively small expense their water-supplies from the deep drift wells. Since this drift extends over most of the northern section of the state, it furnishes a satisfactory source of supply for the rural districts where the municipalities use the deeper well waters. Only 10 per cent. of the cities of 1,000 inhabitants or more in the northern part of the state are without municipal water supplies.

In the western half of the central part of the state and in that part of the state south of a line

drawn from St. Louis to Danville the drift is not deep enough to furnish sufficient reservoir capacity, and it is necessary to rely on surface waters for municipal supplies, and the shallow-dug wells for the rural supplies. Very few of the surface water-supplies in this section of the state have been filtered. The unfiltered water-supplies are not only unattractive for drinking, but they may be contaminated or may even be infected. With unattractive municipal supplies a large majority of the citizens in the southern section use water from shallow wells. Under such conditions we expect a higher typhoid fever death-rate in the southern part of the state than in the eastcentral and northern parts.

A study of the statistics collected by the State Board of Health from 1904-19112 shows this to be the case. Dividing the state into two parts, fifty-one counties to the north and the same

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number to the south, we find in the northern part of the state but two counties with a typhoid fever death-rate exceeding 30 per 100,000, and not one. county with a typhoid fever death-rate of 40 per 100,000. Sixteen of these northern counties had a rate below 10 per 100,000.

In the southern part of the state there were five counties with a typhoid fever rate of more than 40 per 100,000, and twelve more with a typhoid death-rate of more than 30, and but one

We have carefully classified all well waters sent to the Survey for examination during the years 1907-12. (See Table 1.) The waters received have been classified according to depth as follows: Less than 25 feet, 25-50 feet, 50 to 100 feet, over 100 feet, and unknown. The variation in the quality of each class from year to year is but slight. (See Diagram 1.) The average number condemned decreases with the depth of the well. The wells are condemned from the analysis con

with a rate below 10 per 100,000. It is gratify-sidered in conjunction with the source of the ing to note that the average for the eight years, 1904-11, is better than the average for the five years, 1304-08.

2. Proceedings Illinois Water Supply Association, ii, 151-164.

water and the surroundings of the well. The condemnation is not because of the known presence of disease germs, but because of the presence of filth and the possibility of infection. Of

those wells less than 25 feet in depth, 76 per cent. were condemned; of those 25 to 50 feet, 63 per cent. were condemned; of those from 50 to 100 feet, 32 per cent. were condemned; of those over 100 feet in depth, only 15 per cent. were condemned; and many of the deepest were condemned because of the excess of the mineral content and not because of contamination. Of those of unknown origin, 45 per cent. were condemned. Of all the well waters received during the six years, 47 per cent. were condemned. We note an improvement in the character of the waters received for analysis and a decrease in typhoid fever during the latter part of the five-year period.

Without doubt the above does not give the true idea of the actual condition of the water obtained from all wells throughout the state. As a matter

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of fact, a majority of the samples sent to the Water Survey for examination are sent because of typhoid fever cases among those using the water. A truer estimate of the actual character of the well waters of the state can be obtained from a study of water collected by representatives of the survey from typical wells.3 A small number of samples collected by representatives of the Survey from farm wells in various parts of the state have been examined. While 73 per cent. of those less than 25 feet deep were condemned, only 54 per cent. of those from 25 to 50 feet, 13 per cent. of those from 50 to 100 feet, and

3. University of Illinois Bulletin, Water Survey Series, No. 7, 78-97.

100-over.

Ave. for 5 years. 100 representative wells.

The results of the examination of the water from shallow wells showed three-fourths of them to be contaminated and possibly dangerous. An ideal remedy would be to abolish all shallow-dug wells, but the ideal cannot be attained in this as in many other matters. As indicated in the discussion of the sources of water-supplies in the state, it is impossible in some parts of the state to obtain a satisfactory water from deep wells so that the shallow well is a necessity.

Whenever the water-bearing stratum is porous enough to allow free flow, a driven or bored well less than 50 feet deep should furnish a satisfactory water. In many cases, however, the flow through the water-bearing stratum is so small.

that it is necessary to make a reservoir into which the water may slowly percolate and from which it can be drawn as needed. Hence the shallowdug well is a necessity. Granting that it is a necessity, great care must be taken to protect the water. The character of the strata which it penetrates must be taken into consideration.

Strata of sand may serve as a filter to purify the water. Strata of clay or other material through which water may flow in crevices or cracks may allow pollution to be carried considerable distances. Wells should be located on a higher level and at a distance from any cesspools, privies or barnyards. The immediate surroundings of the well must be carefully protected. Surface water should not be allowed to pass through the casing within at least 4 feet of the top. The cover should be tight so that water from the pump may not flow back into the well carrying with it any dirt and filth from the well cover.

If typhoid fever does break out, we wish to emphasize the fact that about the last thing to do is to send water for examination. Typhoid fever infection has taken place from ten days to two weeks before the symptoms are recognized. There are other means of spreading typhoid fever, and even if the water were the means, during the time between infection and the outbreak of the disease the water in the well may have lost its infection. Rather should the patient be so cared for that he may not again infect the well or infect others by contact. The water may be analyzed, but it will require from one week to ten days to obtain the results of an analysis, and in the meantime infection may have spread through other means. It is the wisest course to protect all wells so that infection cannot enter, making the water safe at all times.

DISCUSSION

Dr. A. Gehrmann, Chicago: I should like to ask Professor Bartow to state if there was any record made of the covering of the wells in relation to depth

and reasons of condemnation. There is in the shallow well almost of necessity a bad condition in that not alone the people but also farm animals walk on the top of the well and contaminate it directly

through a loose cover. If we could keep these feet

off the top of the drinking well, contamination would be much less. The pump should be to one side and not directly over the well. The common way of arranging a well and walking all over the top is one of the worst violations of sanitary principles that we have.

VITAL STATISTICS AND WATER

SUPPLIES *

PAUL HANSEN

Engineer State Water Survey
URBANA, ILL.

A striking fact is that in the absence of accurately kept vital statistics, the public, even the well-informed part of the public, has a very vague and inaccurate notion of the health conditions in a community. This fact is interestingly illustrated by Dr. W. S. Rankin, Secretary

of the North Carolina State Board of Health. In a community of 20,000 he called by telephone five of the most representative and intelligent citizens and requested them to answer two questions without asking any explanations as to why the questions were put. The five men were, respectively, a college president, a public official, a practicing physician, a banker and a leading merchant. The first question was, "What is your opinion of the health of your city?" As if their patriotism had been called into serious question they all unhesitatingly answered "good." The second question was, "How many people would you say died in your city last year?" Since the first question had committed them to some pretence of knowledge it was necessary for them, after verbal sparing, to make a bluff at the

Three guessed 60 deaths, one guessed 100 and one 300. As a matter of fact, there were

508, an exceedingly large number for a community of this size and of course a very large percentage of the deaths were from preventable. diseases. The combined guesses of the five persons was only 72 more than the actual number.

In the city to which Dr. Rankin referred, it was possible at least to get the total death-rate, but in most of the smaller cities of Illinois, it is not possible to do so without laborious searching in the county court house. So in the great majority of Illinois communities that have watersupplies it is impossible to demonstrate any relation between this utility and the healthfulness of the community. This status of affairs is particularly unfortunate in those communities having water-supplies which are known from ocular and analytical evidence to be contaminated. to some peculiar psychologic condition there are only two things which have weight in convincing the public that a water-supply is bad, namely, strong proof that the water is killing people, or the presence of some harmless mud-the latter

Due

* Read at the Sixty-Third Annual Meeting of the Illinois State Medical Society, at Peoria, May 20, 1913. Section of Public Health and Hygiene.

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is likely to have the greater weight. Fortunately for the advance of sanitation the presence of mud is generally an indication of the presence of more serious contamination.

Water-borne diseases are so characteristically shown by accurately kept vital statistics that it is of great importance to water works men that such statistics be maintained and made readily accessible. They enable one, in the case of polluted water-supplies, to show at what expense measured in sickness and death, these supplies are being maintained, and if sickness and death is not sufficiently intelligible as a measure, then the expense can actually be reduced to dollars and cents by very interesting methods suggested by Whipple.1

With complete and accurate vital statistics it would no doubt be feasible to establish a clearer relation between water-supplies and diseases other than typhoid. Such a relation was first enunciated by Mills in our own country and Reinke in Germany. Later, in 1904, Hazen gave this relation a rough quantitative expression by stating that for every typhoid fever death two or three deaths were prevented from other causes. More recently Sedgwick and McNutt have, by more elaborate statistical studies, given us a better figure which is an even greater ratio than that expressed by Hazen, namely, five or six deaths to one from typhoid. Though their discussions are very suggestive, these investigators have not succeeded in demonstrating clearly what these other diseases are and to what extent they exist. Good vital statistics maintained throughout the country, after careful analysis, cannot fail to throw more light on this interesting phase of the relation of water-supplies to public health. Not only this, but it will shed a new light on many of the obscure diarrheal diseases, more particularly diarrheal diseases of children.

A most important part of the maintenance of vital statistics from the point of view of the water works man is the prompt registration of all cases of transmissible diseases as well as deaths, more particularly those which are waterborne. These should as soon as practicable be extended to include various bowel disturbances which are not considered fatal or which are not clearly defined as specific diseases. With these

1. George C. Whipple, Consulting Sanitary Engineer, New York City, and Prof. of Sanitary Engineering at Harvard College.

2. Hiram Mills, Engineer, member Mass. State Board of Health.

3. Reinke, Director of Public Health, Hamburg, Ger

many.

4. Allen Hazen, Consulting Sanitary Engineer New York City.

5. Prof. Wm. T. Sedgwick, Mass. Institute of Technology.

otherwise

and diseases properly tabulated arranged from day to day the health of a community may be kept under firm control and epidemics may be promptly halted. By the aid of these figures water-supplies may be subjected to the supreme test, namely, their relation to the health of a community. Analyses and inspections may do much, but after all the vital statistics of a community speak most eloquently for or against a water-supply and constitute the only conclusive measure of its quality.

Many striking facts may be deduced by skillful handling of vital statistics and a few of the most frequently used devices should interest members of the sanitary section of the Illinois State Medical Society.

The first is the "spot map," or map on which are recorded by means of colored dots or tacks the location of cases. These maps are most illuminating as a first step in ascertaining the origin of an epidemic. If uniformly distributed throughout a community they suggest a generally active cause, such as a public water-supply. If restricted to a certain section, milk or a polluted well may be suspected as the cause.

Diagrams showing the daily, weekly, monthly and yearly distribution of cases and deaths are instructive in throwing light on the time when infection was active and combined with the information given by the spot map may throw much light on the source of infection.

Where typhoid fever or other disease occurs for an extended period of time and its distribution is modified by a variety of causes, an elaborate chart may be made, such as that devised by Whipple to illustrate typhoid conditions in Cleve

land. This shows in addition to the incidence of typhoid fever, the rainfall, flood conditions in the Cayahoga River, wind direction and velocity and periods during which water was drawn from the old and the new water works intakes.

Some interesting diagrams were devised by Sedgwick and Winslow to show the relation of typhoid to temperature under varying conditions for a number of cities and countries. To get smooth and representative curves, they plotted the monthly averages of typhoid fever and temperature for a long series of years. To bring out the relation more strongly, the temperature curves were set forward two months, which allowed approximately for the average time which elapses between infection and death. These curves show in a most striking manner that when uninfluenced by a polluted water-supply the annual dis

6. Prof. C. E. A. Winslow, College of the City of New

York.

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