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GENEVA

HERMANN M. BIGGS, M.D., State Commissioner of Health:

I beg to submit the following report upon the installation of this Department's emergency sterilization apparatus in connection with the public water supply of Geneva, N. Y.

Following a request from the local health officer, Dr. C. D. McCarthy, and authorization by the board of public works, the emergency apparatus was installed by assistant engineers, E. S. Chase and C. M. Baker and put into operation on November 30, 1917. The public water supply of Geneva, derived from Seneca lake, is subjected to purification by slow sand filters, but owing to insufficient capacity of the purification plant it has been necessary at times to pump raw water into the distribution system. Since July of the present year some 15 cases of typhoid fever have occurred in the city and the evidence given the engineering division points to the water supply as the probable cause of this undue prevalence of typhoid. In order, therefore, to obviate the continued danger arising from the use of the raw water, the installation of the sterilization apparatus of this Department was requested.

The water supply of Geneva is treated by two units of slow sand filters each one-fifth of an acre in area. From the filters the water enters a clear water basin of approximately 500,000 gallons capacity thence to a pump well whence it is pumped to the distribution system, any excess over consumption going to a one million gallon concrete reservoir on a hill south of the city. A complete description of the waterworks system will be found in a report upon an investigation of the supply made by the engineering division in 1914, this report being published in the 35th Annual Report of this Department, Vol. 2, page 336.

The present daily water consumption is approximately 2.2 million gallons while the total capacity of the two filter units is not over 2 million gallons daily, consequently at times it has been necessary to admit raw water into the pump well from which the filtered water is pumped to the city. Furthermore, when one filter unit is cleaned, the reserve storage of filtered water is insufficient to make up for the deficiency brought about by the reduced capacity of the filter plant and it becomes necessary to use a larger proportion of raw water than under ordinary conditions.

The unsafe sanitary quality of Lake Seneca water has been pointed out by this Department at various times in the past. The sewage of Geneva enters the lake at its northern end and, while under normal conditions it probably flows from the lake through the outlet, under certain conditions of wind and lake currents sewage contamination reaches the waterworks intake. This conclusion has been repeatedly confirmed by analyses made by this Department and by chemists employed by the city. Furthermore, prior to the installation of the filter plant, Geneva experienced a continued excess of typhoid fever, this prevalence being materially reduced following the purification of the water supply. During the past summer and fall, numerous analyses made by Mr. Harold Macy, city bacteriologist, indicate the frequent occurrence of organisms of the B. coli type in the water as delivered to the city. Analyses of the filtered water, without admixture of raw water, indicate that the filters have been operated efficiently. It is, therefore, evident that the contamination found in the sample from the distribution system has been due to the mixture of untreated water with the filter effluent. In this connection it is interesting to note that 12 of the 15 cases of typhoid had dates of onset reported as occurring within a period of one month from about the second week in October to the second week in November and that, in the ten days to three weeks incubation period prior to each of these onsets, cleaning of the filters occurred and consequently short periods during which comparatively large amounts of raw water were pumped to the mains. At the time of a cleaning which occurred on September 22, the wind had been from the north and northeast and under such a condition it is conceivable that at this time when considerable quantities of raw water were being used, infection from the city sewage reached the intake.

Early in 1916 the necessity for pumping raw water into the mains was first brought to the attention of this Department. A letter dated February 2, 1916, was accordingly addressed to the mayor advising the installation and operation of a chlorine apparatus for sterilization of the supply in order to avoid the danger arising from the use of raw water. It was also pointed out that provision should be made for the addition of a third filter unit. Similar advice was again given in a letter dated March 11, 1916. Although a third filter unit of 1.5 million gallons daily capacity was contracted for and is now nearing completion, no action was taken towards installing the chlorine apparatus prior to the request for the apparatus of this Department.

Samples of the raw, filtered and chlorinated water were collected after the recent installation of the chlorinator and the results of the analyses of these samples made by the Division of Laboratories and Research will be found in the appended table.

These results show a raw water containing a moderate amount of active contamination as indicated by the occurrence of organisms of the B. coli type in 10 c.c. inoculations. That the filters were operating effectively at the time of collection is shown by the low bacterial counts and absence of B. coli in the samples of filter effluents. Although raw water was being mixed with the filtered water, the analysis of the chlorinated water as delivered to the city shows that the chlorination process was effective in maintaining the supply in a satisfactory sanitary condition.

In view of the above facts the following conclusions may be drawn:

1. That, with the evidence available, it appears probable that the admixture of untreated water with the filtered water has been responsible for an infection of the public water supply of Geneva and for the resultant undue prevalence of typhoid recently occurring.

2. That the installation and operation of the emergency chlorination apparatus of this Department provided a means for rendering safe the mixed supply.

3. That, although the completion of the new filter unit will largely make unnecessary the use of unfiltered water, the installation of a permanent chlorination apparatus would furnish an additional safeguard against the delivery of raw water to the city at times of emergency and would also serve as a valuable adjunct to the filter plant.

I would recommend, therefore, that, as previously advised by us in our letter of 1916, the city install and operate permanent apparatus for the sterilization of the supply, such treatment being available for emergency use and for supplementing filtration.

In conclusion, I would recommend that copies of this report be transmitted to the mayor, the board of public works, the health officer and to the sanitary supervisor of the district.

Respectfully submitted,

THEODORE HORTON,
Chief Engineer

ALBANY, N. Y., December 29, 1917

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Results are expressed in parts per million. + Present.

Absent.

Abbreviations used to describe odors of water: 0, none; 1, very faint; 2, faint; 3, distinct; 4, decided; 5, strong; 6, very strong; a, aromatic; d, disagreeable; e, earthy; f, fishy; g, grassy; m, musty; v, vegetable.

GILBERTSVILLE

HERMANN M. BIGGS, M.D., State Commissioner of Health:

I beg to submit the following report on an investigation of the public water supply of Gilbertsville made by Mr. C. M. Baker, assistant engineer, on July 26, 1917.

Gilbertsville is an incorporated village having a resident population of about 450 inhabitants which, however, is increased somewhat during the summer months due to summer residents. The village is located in the easterly portion of Otsego county on Butternut creek. It is 5 miles northeast of Mt. Upton, the nearest railroad station which is located on the New Berlin branch of the New York, Ontario and Western railroad.

The supply was originally put into operation in 1896 and is derived from Dunderberg creek. It was formerly taken from a small impounding reservoir located about 14 miles above the village, the only purification being through gravel in the bed of the stream. The report on a previous investigation of this supply by this Department may be found on page 338 of the 29th Annual Report. Due to shortage of water at times, also to its questionable sanitary quality, a new storage reservoir and purification plant has been recently constructed, having been completed and put into operation about September 1, 1916.

The supply is owned and operated by the village under the direction of the board of trustees. From the impounding reservoir, which is located about one-fourth of a mile above the village, the water flows by gravity through slow sand filters located directly below the reservoir, thence to a chlorination plant and distribution reservoir located on a hill just north of the village, from which the water is distributed by gravity through the distribution system. Practically all of the inhabitants of the village are served with the water, there being between 160 and 170 service taps, none of which are metered. The pressure averages about 75 pounds per square inch. According to recent meter readings the consumption ranges from 125,000 to 150,000

gallons per day, an equivalent of 278 or 320 gallons per capita, a very high rate of consumption.

The impounding reservoir is formed by the construction of an earthen dam with concrete core wall across the natural channel of the stream. The capacity of the reservoir is estimated to be about 7,000,000 gallons. About three-eighths of a mile above this reservoir is a second dam which diverts the flow of the stream through an artificial channel discharging below the impounding reservoir and purification plant. The water from the main channel of the stream is controlled by gate valves and is not ordinarily discharged into the storage reservoir, there being numerous springs about the reservoir which under ordinary conditions furnish ample supply. Provision is made, however, whereby water may be drawn directly from the diverting channel to the filters or to the distributing reservoir. The distinguishing reservoir is constructed of stone and concrete, is 40 y 60 feet in plan by 10 feet deep and has a capacity of about 175,000 gallons. It is covered with a wooden roof.

The watershed tributary to the supply has an area of about 4.1 square miles and a total population of about 125 persons which is equivalent to approximately 30 per square mile. The land is used for farming and agricultural purposes. The slopes are in general quite precipitous. Approximately 10 per cent of the area is wooded. The following conditions, indicating the general sanitary conditions on the watershed, were observed at the time of the inspection:

1. At a farm located three-fourths of a mile above the reservoir owned by the Jenson estate and occupied by Edson Harris, the barn and other buildings are located at the top of a steep slope leading to the stream, the barn being about 60 feet distant. The privy is located about 75 feet from the stream and a drain which receives drainage from a sink and also from a cellar passes within 8 feet of the privy, thence to the stream. 2. At a farm 134 miles above the reservoir a brook runs between the road and buildings, the house, however, is located about 100 feet from the stream and other buildings about 200 feet distant.

3. At a farm 24 miles above the reservoir owned and occupied by Fred Young, the barn is 50 feet from the stream and the barnyard is directly on the stream. The drainage from the gutter back of the cow stanchion leads directly to the stream.

4. At a farm located nearly opposite the reservoir and owned by the J. T. Gilbert estate, a small brook passes between the house and barn. This brook discharges into the diverting channel and is tributary to the supply only in case water should be drawn directly from the diverting channel, as at times when the storage reservoir is being cleaned. Although these premises were not occupied at the time of the inspection, it is obvious that should they be occupied and insanitary conditions maintained, pollution of the supply would result therefrom in case it is necessary to draw directly from the diverting channel. The purification plant consists of slow sand filters and is supplemented by liquid chlorine sterilization. A screen chamber is located in a control house between the impounding reservoir and the filters. The filters consist of two units of slow sand filters having a total area of .072 acre. The two units are formed by a division wall through the center of the filtration area which is provided with suitable regulating gates. Aeration is provided in one of the filters by means of 7 nozzles which form a spray as the water enters this filter. The filtering medium consists of about two feet of sand resting upon a foot of graded gravel. The sand, according to the specifications, has an effective size of about 4 millimeter. The collecting system consists of a 10-inch main collecting pipe with 8-inch laterals. Both filters are operated continuously, provision being made, however, to clean one at a time. The rate of filtration based upon a consumption of 125,000 gallons per day is equivalent to 1,740,000 gallons per acre per day, and upon a consumption of 150,000 gallons 2,080,000 per acre per day. It has not been necessary to clean

the filters since their installation, it being the intention of the operator to clean the filters once each spring and fall.

The plant for sterilizing the water with liquid chlorine is located in the operating house at the distributing reservoir and was designed by Wallace & Tiernan Co. It consists of a tank in which a chlorine solution is made by filling the tank with water and then discharging a certain amount of chlorine into this water through a diffuser, the amount of chlorine being weighed by scales on which the chlorine cylinder sets. The chlorine solution is then discharged into the supply through an orifice tank provided with a float valve to maintain a constant head. Due to recent rains the door of the operating house had swollen so that it could not be opened at the time of the inspection and the chlorine plant was not then in operation. The solution tank is said to be about 4 by 8 feet in plan by about 41⁄2 feet deep; 18 ounces of chlorine are applied at one time and it requires three days to empty the tank. It is thus apparent that 6 ounces of chlorine are used each day, when the plant is in operation, which is equivalent to about .36 part per million of chlorine when the consumption is 125,000 gallons per day. This amount should be ample for satisfactory sterilization under ordinary conditions.

Samples of the water were collected at the time of the inspection and sent to the Division of Laboratories and Research for analyses, the results of which are recorded in the appended table.

The results of these analyses show a raw water somewhat high in color and slightly turbid. The bacterial count is moderate, but colon bacilli were found present in all of the 10 c.c. inoculations and in one of the three each of the 1 and 1/10 c.c. inoculations, thus indicating the presence of active contamination. The results of the analysis of the sample collected from a tap in the village show a colorless and clear water. The bacterial count is high and colon bacilli were found present in two of the three 10 c.c. inoculations, thus indicating that all of the active contamination had not been removed by the process filtration.

As a result of this investigation it may be concluded:

1. That the water supply of Gilbertsville is derived from a source which is subject to considerable pollution by inhabitants and transient visitors upon the watershed;

2. That proper operation of the purification plant should remove the pollution and render the supply satisfactory for potable purposes;

3. That at the time of the inspection, the chlorine plant was not being operated, which was probably in part the cause for the ineffective purification being obtained.

In view of the above I beg to recommend that the village authorities provide more careful supervision of the plant in order that continuous and effective operation of the chlorine plant and filters may at all times be maintained.

Finally I would recommend that copies of this report be transmitted to the local officials and to the sanitary supervisor of the district.

Respectfully submitted,

ALBANY N. Y., October 18, 1917

THEODORE HORTON,
Chief Engineer

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