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10. That whenever required by the State Commissioner of Health detailed plans for the intercepting sewers and for the proposed pumping station in District 5A shall be submitted for approval.

11. That detailed plans of the proposed sewer and screen chamber in District 5C shall be submitted for approval before the construction of this sewer and screen chamber.

12. That whenever required detailed plans for the interception and more complete treatment at a suitable point of the effluent from the several proposed sewage disposal plants shall be submitted to this Department for approval; and any or all portions of such works shall be constructed and put in operation at such time or times thereafter as said Commissioner may designate.

March 2, 1917

LINSLY R. WILLIAMS,

Acting State Commissioner of Health

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

I beg to submit the following report on our examination of the plans for a proposed sewage pumping station and of certain intercepting sewers for the village of Larchmont, Westchester county, submitted to this Department for approval by the trustees of the village on September 26, 1917.

The records of the Department show that plans for sewage disposal for the entire village were approved on March 2, 1917, on the condition that whenever required by the State Commission of Health detailed plans for the intercepting sewers and for the proposed pumping station in District 5-A should be submitted for approval. It is in compliance with this condition that the present plans have been submitted.

The section that will be served by the intercepting sewer and pumping station is designated on the map showing the location of the sewers of the village as District 5-A and comprises an area of a little over 200 acres in the northwestern corner of the village. The sewage from a part of this district known as the Larchmont Park section is at present conveyed to a small pumping station located near the lower end of Lincoln Street from which it is pumped over the ridge into sewers of District No. 1. Several complaints have been received by this Department in reference to the insanitary conditions caused by the failure of the owners of this pumping station to keep it operating satisfactorily. It appears from the report of the consulting engineer that the plant is of obsolete design and entirely inadequate to serve the needs of the district tributary to it.

The proposed pumping station is to be constructed at the foot of Oak avenue near Premium creek, a location to which all the sewage from District 5-A can readily be drained by gravity. The plant consists of a screen chamber, suction well, overflow well, and a pump-room housing two horizontal centrifugal pumps arranged to be driven either by electric motors or a gas engine. The building is approximately 25 feet by 30 feet, and extends 26 feet below the surface of the ground. The portion below ground level is of reinforced concrete, and the superstructure, one story high, is of brick. The flow line of the inlet sewer is 21 feet below mean tide and 92 feet below the surface of the ground. A gas heater is provided in the building to keep the interior above freezing temperature in cold weather.

The sewage. on reaching the station. first passes through an inclined bar screen approximately 5 feet square of 22 by 4 inch bars set 4 of an inch apart and then flows into a suction well from which, under normal operating conditions, it is raised by one of the centrifugal pumps and discharged through a 10-inch force main along St. Clare avenue into the 12-inch sewer on Willow avenue.

Two pumps are provided. each capable alone of caring for the maximum flow that will probably be received at the station at any time for a reasonable future period. The pumps are of the horizontal shaft double suction

type, direct connected to 10 horsepower slip-ring motors and arranged so that in case of emergency either, but not both, may be operated by the 15 horsepower gas engine to which both pumps are connected by means of clutches and a silent chain drive. The capacity of each pump is to be 350 gallons per minute and the minimum size of the suction and discharge nozzles is to be 5 inches. Both suction and discharge pipes are increased to 8 inches immediately beyond the pump.

The specifications require that the pump casings shall be so designed that by the substitution of different impellers and the installation of larger (15 horsepower motors the pumps will deliver 600 gallons per minute. This provision makes it possible to easily increase the capacity of the plant so that it will serve the needs of any population that may reasonably be expected to live in the district when it is entirely built up assuming that the sewers in the district are properly constructed with tight joints to prevent the infiltration of ground water.

Automatic float operated switches are provided for starting and stopping the motors, arranged to start one of the pumps when the sewage in the pump well rises to a predetermined level and to stop it when it drops to another level. If one pump does not stop the rise of sewage in the well, the second pump will be automatically started. The pumps are set below the level of the flow line of the inlet sewer and will, therefore, start without priming. The engineer's report recommends that an alarm be connected with one of the floats with the bell in the attendant's house to notify him if the pumps fail to work and the sewage rises above a certain level. Should the motors or the pumps for any reason fail to operate, the sewage will overflow from the suction well into the overflow well which is a concrete chamber located below the floor of the pump room, having a capacity of 30,000 gallons or about 3 hours average flow. Stop-boards are provided below the screen so that should it become necessary the sewage can be by-passed around the suction well into the overflow chamber. Branch suctions, 4 inches in diameter, from the pumps extend into this overflow chamber by which it is possible to pump out its contents.

If the attendant fails to start the pumps in operation before the overflow chamber is filled the sewage will back up in the sewer and escape through a relief pipe into Premium creek. In view of the fact that the plans provide for a duplicate pumping plant and an overflow well of ample capacity to care for the flow while ordinary repairs are being made, the installation of this relief pipe seems unnecessary. Its installation is, moreover, undesirable because by putting up the stop-boards of the screen chamber the entire flow of sewage can be by-passed into the creek. It would seem advisable, therefore, to omit it.

At the foot of St. Clare avenue a 6-inch blow-off pipe is arranged so that the contents of the force main can be discharged into Premium creek. This blow-off pipe is open to the same objection that the relief pipe is. There seems to be no reason why the force main cannot be drained into the overflow well, and the piping should be re-arranged so that this can be done.

To collect the sewage from the present sewers, the plans provide for a 15-inch trunk sewer or intercepting sewer from the present pumping station at the foot of Lincoln street to the location of the new station at the foot of Oak street. The sewer is to be laid on a .25 per cent grade, and will have ample capacity to care for the sewage of the district. Manholes are provided at all changes in alignment and at intervals of about 300 feet on the straight runs. No detailed plans are provided for a trunk line to care for the southern end of District No. 5-A but a connection for a future 10-inch sewer is indicated at the inlet manhole at the pumping station.

In view of the results of our examination of these plans and after a careful consideration of the essential features of the design, I beg to recommend that the plans be approved on the following conditions:

1. That the relief pipe at the manhole first above the pumping station be omitted.

2. That the blow-off pipe shown on the force main at the foot of St. Clare avenue be omitted.

3. That a detailed plan of the intercepting sewer for the southern portion of District 5-A be submitted to the Department for approval before that line is constructed.

4. That detailed plans of the sewers in Willow avenue, Monroe avenue, Cherry avenue and Bonnet avenue so designed as to permit of conveying the sewage from District 5-A and the Cherry avenue section to the Bonnet avenue works be submitted to this Department for approval before the construction of the pumping station or the Bonnet avenue sewage treatment plant.

ALBANY, N. Y., October 3, 1917

The plans were approved Oct. 5, 1917.

Respectfully submitted,

THEODORE HORTON,
Chief Engineer

MASSENA

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

I beg to submit the following report on our examination of plans for proposed sanitary sewer extensions in the village of Massena, St. Lawrence county, submitted to this Department for approval by the village engineer on behalf of the Board of Trustees on June 25, 1917.

The village of Massena which had a population of 4,614 in 1915 according to the last State census, is situated on the Grasse and Raquette rivers, about 7 miles above the confluence of the Grasse and St. Lawrence rivers and about 5 miles from the Canadian boundary line. The records of the Department show that plans for a comprehensive sewer system covering practically the entire village and discharging into the Grasse river at two points and into the Raquette river at one point, were approved on February 14, 1900. Provisions were also made by these plans for the treatment of the sewage in a chemical precipitation plant to be located at each outlet and to be constructed when necessary. On June 27, 1909, plans for proposed sewers in the Pine Grove addition of the village were approved.

Plans now submitted provide for the construction of some 3,000 feet of sanitary sewers in Grove street, Ridgewood avenue, Walnut avenue, Laurel avenue, East Ovis street and through private property between East Ovis street and Water street, discharging into the Grasse river through one of the existing outlet sewers. The proposed sewers are to vary from 8 to 16 inches in diameter and are to be constructed with slopes of from .5 per cent to 4.25 per cent. Manholes are to be constructed at all points of slope and alignment and the maximum spacing between manholes will not exceed 400 feet.

The lower sections of the proposed sewers appear to have been designed with capacities somewhat larger than necessary to care for the sanitary sewage of the section to be served by them. This, however, is not a serious objection inasmuch as it will permit of making extensions to the sewers without danger of overtaxing them in the future. The sewers if properly constructed should satisfactorily meet the requirements for which they were designed. The dilution afforded by Grasse river is large and no public water supplies are obtained from the river below the village.

In view of the above I would recommend that the plans be approved and a permit be issued allowing the discharge into Grasse river of sewage to be collected by the proposed sewers.

Respectfully submitted,

ALBANY, N. Y., June 29, 1917

THEODORE HORTON,
Chief Engineer

PERMIT

Application having been duly made to the State Commissioner of Health, as provided by section 77 of chapter 49 of the Laws of 1909, the "Public Health Law," as amended by chapter 553 of the Laws of 1911, constituting chapter 45 of the Consolidated Laws, permission is hereby given to the Board of Trustees of the village of Massena to discharge sewage from the proposed sewer extensions in Grove street, Ridgewood avenue and East Ovis street and through private property into the waters of the Grasse river through existing outlet sewers within the municipality of Massena in accordance with the plans accompanying the petition, under the following conditions:

1. That this permit shall be revocable at any time or subject to modification or change when in the judgment of the State Commissioner of Health such revocation, modification or change shall become necessary.

2. That the issuance of this permit shall not be deemed to affect in any way action by this Department on any future application that may be made for permission to discharge additional sewage or effluent into the waters of this State.

3. That only sanitary or domestic sewage and no storm water or surface water from streets, roofs or other areas shall be admitted to the proposed sewers.

June 29, 1917

M. NICOLL, Jr., Acting Deputy State Commissioner of Health

MT. PLEASANT (John T. MacCurdy)

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

I beg to submit the following report on our examination of plans for sewage disposal for the property of Dr. John T. MacCurdy near Pleasantville in the town of Mount Pleasant, Westchester county, resubmitted to this Department for approval on April 14, 1917.

Location

The property is located about one mile west of the Pleasantville R. R. station. It is on the watershed of the Pocantico river which is used as a source of water supply furnished by the Consolidated Water Company of Suburban New York to the village of North Tarrytown and neighboring communities in Westchester county after filtration in pressure mechanical filters and sterilization with liquid chlorine.

General description

According to the reports submitted by the designing engineers, the maximum population to be cared for will be 18 persons and the daily water consumption is estimated at 1,800 gallons. The soil at the disposal site is claimed to be a heavy loam and the ground water is said to be at a depth of about 5 feet below the surface of the ground.

Plans for the disposal of the sewage from this property in a sewage disposal plant consisting of settling tanks, dosing tank and an artificial under-drained subsurface irrigation system were first submitted for approval on March 13, 1917. It was found from our examination of these plans that although they had been designed in general to meet the local requirements for sewage disposal, the subsurface irrigation system was designed to operate at an excessively high rate. The plans were accordingly returned to the designing engineers with the recommendation that they be so revised as to provide for a rate of operation of not higher than 30,000 gallons per acre per day. A conference was subsequently held with the designing engineers in this office when the

design of the disposal plant was reviewed. The engineers were advised that alternate plans providing for a subsurface irrigation system containing 100 feet of distributing tile per person would be considered. Plans designed along these lines were submitted for approval on April 14, as noted above.

Sewers

These plans show that sewage from the main building is to be conveyed to the sewage disposal plant through some 350 feet of 6-inch vitrified tile pipe laid on a fairly steep slope. The sewage from the barn on the property is to be conveyed to the disposal plant through some 700 feet of 4-inch pipe laid with a slope of from 1.5 to 2.97 per cent. Some 250 feet of the upper portion of this sewer is to pass near and across two small streams and is, therefore, to be constructed of cast-iron pipe. The remainder of this sewer is to be of vitrified tile pipe.

Sewage disposal

The sewage disposal plant is to consist of two settling tanks, dosing tank and subsurface irrigation system. The settling tanks, which are to be covered, are to be operated in a series. The first tank is to be 6 feet in diameter and 6 feet deep below the flow line and the second tank is to be 5 feet in diameter and 6 feet deep below the flow line. The combined capacity of these tanks will be about 2,000 gallons and will, therefore, provide for a detention period of the sewage of approximately one day on the basis of design used, namely, a flow of 1,800 gallons per day.

Sludge disposal

No provisions have been made by the plans for the disposal of sludge from the settling tanks. It is important that the sludge should be removed from the settling tanks at least once a year, especially from the first settling tank where most of the sludge will probably accumulate. For a small plant of this kind, the sludge could either be removed by bailing or by pumping it out with a diaphragm pump into watertight barrels or other suitable containers. The sludge should be properly buried or placed in trenches and covered over at a distance of not less than 300 feet from any stream or watercourse tributary to the Pocantico river, as required by the rules and regulations for the protection from contamination of the water supply furnished by the Consolidated Water Company of suburban New York.

Dosing tank

The dosing tank, which is to be located adjacent to the second settling tank, will have a capacity of 19.5 cubic feet. It is to be provided with an automatic discharge siphon by means of which the sewage is to be discharged intermittently to the subsurface irrigation system.

Subsurface irrigation system

The distributing system of the subsurface irrigation system is to consist of a gate chamber, 3 main distributors, and 12 lines of lateral distributors 150 feet long each. Each main distributor is to serve 4 lines of lateral distributors. The laterals are to consist of special double horseshoe distributing tile laid in trenches with slopes of .25 per cent. The plans indicate that the distributors are to be surrounded with coarse material. The system will contain 1,800 feet of distributing tiling equal to 100 feet per person. It will cover an area of about .27 acres and will, therefore, be required to operate at the rate of about 7,000 gallons per acre per day when serving 18 persons and assuming a daily per capita rate of sewage contribution of about 100 gallons.

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