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HERMANN M. BIGGS; M.D., State Commissioner of Health:
I beg to submit the following report upon a reinvestigation of the public water supply of the city of White Plains. The recent investigation was made on April 26, 1917, by Mr. M. F. Sanborn, assistant engineer, who was assisted at tlie time of the inspection by Mr. Miguel L. Hauck, commissioner of public works.
Location.- Westchester county about 15 miles north of New York city on Harlem Division of the New York Central railroad, and New York, New Haven and Hartford Railroad and the Bronx river.
Population.— 22,000, of which about 99 per cent are served by the public water supply.
Waterworks controlled by Department of public works. Consumption.— 1,500,000 gallons or about 69 gallons per capita per day.
Source of supply.- Small brook, one set of shallow wells and two sets of deep wells, all in northern part of the city.
Distribution system.- Water pumped to standpipe in northern part of the city and 4834 miles of mains from 4 to 14 inches in diameter.
Service taps.- 3,400 services, of which nearly all are metered; 450 hydrants. Pressure. — 85-90 pounds.
Previous investigations of these waterworks were made in 1909 and 1914 and copies of the reports thereon may be found on page 365, vol. 2, of the 1909 Annual Report of this Department, and on page 710, vol. 2, of the 1915 Report, respectively.
In general the waterworks system remains practically the same as in 1914. The 2 reservoirs upon the brook are as described in previous reports, although there are now no buildings upon the watershed above these reservoirg.
The shallow wells are also in about the same condition as described previously. Four are now in use and the two wells west of the main wells are still out of service. The two latter wells are apparently located at natural springs which drain part of the area west and northwest of them. These two wells are probably open to pollution from a cesspool located about 100 feet from and apparently in direct line of ground water flow to the wells. The land surrounding these wells is low and in case water was pumped from them they would undoubtedly receive considerable surface water from the nearby brooks and marsh. The city is soon to construct a sewer through a new street about 150 feet from these two wells and the house near the wells will then be connected to this sewer. If these two wells are to be used again that part of the sewer within 300 feet of the wells should be constructed of castiron and bulkheads constructed in the trench to prevent ground water from passing along the line of the sewer to the ground water reaching the wells. Upon the completion of the sewer the house near the wells should be connected and old cesspool cleaned, disinfected and filled. If a fill of impervious material about 30 feet wide was then placed around each well so as to raise the ground around these wells above high water it is probable that water from these wells might be used during the dry season when the marsh is not flooded.
The 5 deep wells owned by the city are from 80 to 160 feet deep and are located a short distance north of the shallow wells. These deep wells are about 8 inches in diameter and were sunk through various depths of peat, sand and gravel to rock. Not all of these wells are in service, although it is proposed to connect them all for use provided they yield sufficient water.
The other set of deep wells is called the Drew supply. These wells are located about 1 mile northwest of the city wells and are 12 in number, from 6 to 12 inches in diameter and from 85 to 140 feet deep. These wells were driven through various depths of gravel, hard pan and blue clay to gravel. About 9 of these wells are now in use. The Drew wells are owned by the Castle Heights Water Company, of which Mr. John Drew is president. This company has a contract with the city to furnish 800,000 gallons per day to the city.
The pumping station for the Drew supply is located near the wells and is about 50 feet square. This station contains a 125-horsepower and a 100-horsepower boiler, 1 Worthington duplex compound pump 12 inches by 20 inches by 12 inches by 15 inches, capacity 1,500,000 gallons per day, and 1 Worthington pump 12 inches by 22 inches by 14 inches by 18 inches, capacity 2,000,000 gallons per day.
The pumping station for the city supply is located near the shallow wells and is a frame structure about 60 x 80 feet in plan. The pumping equipment consists of 2 Star water tube boilers 125-horsepower each; 2 Worthington triple expansion duplex pumps 10 inches by 16 inches by 25 inches by 14 inches by 18 inches, capacity 2,000,000 gallons each per day; 1 Worthington duplex compound pump 181/2 inches by 12 inches by 10 inches, capacity 1,000,000 gallons; 1 Ingersoll-Rand' type 10 air compressor for raising water from the deep wells to the pump well. This pump well is 30 feet in diameter and 25 feet deep.
Practically all of the watershed of the brook above the reservoir is owned by the city, there are no houses upon the watershed, and the only pollution which the water would ordinarily receive would be from persons or animals passing over the shed. The sanitary condition surrounding the wells (except the two westerly dug wells) is good with the exception that very high water on the marsh might cause the ground surrounding some of the wells to be flooded with consequent infiltration of imperfectly purified surface water into the wells. The two westerly dug wells are at present subject to pollution from the nearby cesspool and from surface water. In rear of the city pumping station there is a privy with a concrete vault about 5 feet square nd 7 feet deep. The privy is apparently kept in a sanitary condition. No toilet facilities are provided at the Drew pumping station.
About 25 pounds of copper sulphate has been used in each reservoir for the past four or five years to kill a small amount of algae growth which has been found in these reservoirs, This amount corresponds to about .03 to .04 parts per million, a very weak application.
At the time of the inspection samples from a tap in the village and from the various sources were collected and the results of the analyses of these samples will be found in the appended table. For analyses made during the past few years reference is made to the reinspection report of May 17, 1915.
From the analyses of the samples taken at the time of the recent inspection, it will be seen that the water from the tap in the village which is a composite sample of all of the sources, is clear, colorless and quite hard. Nitrogen in its various forms is low and the chlorine is about normal for this section of the country. The bacterial count is moderate and no organisms of the B. coli group were found in the inoculations tested. The results of the analysis of the sample collected from the Drew supply show a water similar, although somewhat harder, to the composite sample. The characteristics of the sample from the city deep wells are about the same as those of the tap water with the exception that the figures for chlorine and hardness are smaller. The bacterial counts are moderate and no organisms of the B. coli type were isolated. The water from the shallow wells is somewhat similar to that of the deep well, except that it is somewhat harder. The bacterial count is fairly high, although no organisms of the B. coli group were found in the samples inoculated. The reservoir water is very soft and slightly colored and turbid. The figures for free ammonia, albuminoid and oxygen consumed are moderately high and are probably derived from vegetable organic matter upon the watershed. The number of bacteria are moderate for a surface supply, and no organisms of the B. coli type were found in the samples inoculated.
As a result of this investigation and of the analyses, the following conclusions may be drawn:
1. That the public water supply of the city of White Plains is apparently of a reasonably satisfactory sanitary quality, as shown by the sanitary survey and by the analyses.
2. That the two westerly shallow wells now out of service are unsatisfactory, because of the location of the nearby cesspool and on account of the possibility of receiving surface water.
3. That there are no toilet facilities at the pumping station of the Drew supply, resulting in the possibility of pollution of the ground in the
vicinity of the wells by employees at the station. In view of the above conclusions, I would make the following recommendations:
1. If it is desired to utilize the two westerly shallow wells after the completion of the sewer and the abandonment, disinfection and filling of the cesspool near them, a bank of impervious material about 30 feet wide should be placed around each of the wells, at least 2 feet above the high water level. With this precaution the water from the wells might be used during the drier period of the year. Analyses of the water, however, should be made before these wells are used, and at frequent intervals while in use, in order to determine its freedom from pollution. It is not thought advisable to use these wells at times when the marsh is flooded on account of the possibility of their receiving surface wash.
2. That a toilet with a removable tight container be installed at the pumping station of the Drew supply, and that the contents thereof be removed at frequent intervals and either burned in an incinerator or
under the boiler if buried, at least 500 feet from any of the wells. In conclusion, I would recommend that copies of this report be transmitted to the local authorities, and to the sanitary supervisor of the district.
Chief Engineer ALBANY, N. Y., August 27, 1917
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.
HERMANN M. BIGGS, M.D., State Commissioner of Health:
I beg to submit the following report upon an inspection of proposed sources of public water supply for the village of Winthrop made on May 1, 1917, by Mr. M. F. Sanborn, assistant engineer.
Winthrop is an unincorporated village with a population of 450 located in the town of Stockholm in the northeastern part of St. Lawrence county on the Rutland railroad about 35 miles east of the city of Ogdensburg and on the St. Regis river, near the junction of the East and West branches. The village is unprovided with a sewer system, the houses being served by privies and cesspools.
At present the village has no public water supply, water for domestic purposes being obtained from private wells scattered throughout the village. Realizing the need for a public water supply, the citizens of the village selected a committee to investigate the matter of forming a water district, preparatory to the installation of a supply and preliminary plans for such a supply have been prepared by Mr. A. M. Dowd, civil engineer of Winthrop.
It is proposed to develop a supply by pumping water from a driven well, now used in connection with a milk station, into a distribution system to be constructed of 34 of a mile of 6-inch castiron pipe against pressure to be maintained by an elevated tank which is to have a capacity of 20,000 gallons, and which is to be at an elevation approximately 100 feet above the surface of the ground. It is also proposed to provide an auxiliary intake from the St. Regis river, in order that the supply from the well be augmented at time of fire or other emergency.
The well at the milk station is said to be 6 inches in diameter, driven to a depth of 135 feet. In reaching this depth the well passes through top soil and gravel for 20 feet, and the remainder of the distance through rock, mainly limestone. When the well is not drawn upon, the water of the well is said to rise to a height of 15 or 20 feet above the surface of the ground in the vicinity. The casing of the well is extended to the rock. The pump operated by the milk station is a 41/2 by 31/4 by 6-inch plunger pump. In case the village should secure a supply from this well, it has been suggested that the pump be operated by an electric motor.
The well is located not far from the west bank of the St. Regis river. The privy at the milk station is about 90 feet distant from the well, and beyond 100 feet and within 500 feet there are 8 houses, while beyond 500 feet and within 1,000 feet, there are about 12 houses. These houses are served by privies and cesspools.
The St. Regis river above the point of the proposed intake has a watershed area of approximately 875 square miles. Upon this area there are several scattered hamlets and small villages, chief among which is St. Regis Falls, having a poulation of 1,500, located about 25 miles up stream from Winthrop. The total population may be estimated at 7,000, or 8 per square mile. The stream is evidently unsafe for domestic purposes without purification, and is also unsatisfactory from an aesthetic standpoint on account of its high color.
At the time of the inspection samples of water were collected from a tap at the milk station of the well water and from St. Regis river, near the point of the proposed intake, and the results of the analyses of these samples made by the Division of Laboratories and Research will be found in the appended table.
The results of the analysis of the well water show a water clear, colorless and hard. The figures for free ammonia are somewhat high which, however, is usually of comparatively little sanitary significance in deep well water. Otherwise the analytical results indicate the absence of active or past pollution of the ground water tributary to the well. The total bacterial count is low, and organisms of the B. coli type were not found in the inoculations tested.
The results of the analysis of St. Regis river samples show a highly colored and soft water free from turbidity. The figures for free and albuminoid ammonia are moderately high, and that for oxygen consumed high, indicating the presence of considerable amounts of organic matter, mainly of vegetable origin. The total bacterial count is excessive and fecal organisms of the B. coli type were isolated from inoculations as small as 1 c.c., indicating activ and potentially dangerous contamination. In view of the above facts the following conclusions may be drawn:
1. That the milk station well from which it is proposed to secure a public supply of water for the village of Winthrop, although somewhat unsatisfactorily located with respect to nearby sources of ground water pollution, was apparently furnishing a water free from active contamination and free from marked indications of past pollution at the time of the inspection. This supply, however, has a slight odor of hydrogen sulphide, which renders it somewhat undesirable from an aesthetic standpoint.
2. That the proposed supplementary intake from the St. Regis river would afford opportunity whereby polluted and unsatisfactory water
might be pumped into the distribution system of the village. I would therefore recommend :
1. That in case the well at the milk station be used as a source of public water supply for the village of Winthrop, all privies, privy vaults, cesspools or other receptacles for human excreta within 500 feet of the well be provided with watertight containers from which the contents may be emptied and satisfactorily disposed of at sufficiently frequent intervals to prevent contamination of the ground water.
2. That some form of aeration of the water before pumping into the mains should be provided, in order to remove a large part of the hydrogen sulphide present.
3. That in case this well affords insufficient supply for fire protection, the village sink another well, satisfactorily located, or secure additional supply from any other adequate and feasible source free from possibility of contamination. In no event should provision be made for pumping the St. Regis river water into the mains.
I would further recommend that copies of this report be sent to the local authorities, to the Conservation Commission, and to the sanitary supervisor of the district.
Chief Engineer ALBANY, N. Y., June 27, 1917