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of Sewer Commissioners, Sewer District No. 1, town of New Hartford, to discharge sewage from the proposed sewers in Fairfax place and Cornwall place into the waters of a branch of Sauquoit creek through the outlet of the sewage disposal plant of this sewer district within the town of New Hartford, 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 charge when in the judgment of the State Commission 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 or the sewage disposal works.

4. That all the sewage to be collected by the proposed sewers shall be passed through the sewage disposal works of Sewer District No. 1, town of New Hartford.

M. NICOLL, JR.,

Deputy State Commissioner of Health. August 1, 1917

NEW HARTFORD (Standard Silk Co.)

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

I beg to submit the following report on an examination of plans for sewage and sewage disposal for a portion of the unincorporated village of Chadwicks, town of New Hartford, Oneida county, on the property of the Standard Silk Company.

These plans were first submitted for approval by the Standard Silk Company on July 16, 1917, and after a preliminary examination of them by the engineering division and a conference in this office with the designing engineer they were returned for revision on August 22, 1917. On August 27, 1917, these plans, revised in general to meet the requirements of this Department, were again submitted. The plans comprise duplicate copies of the following:

1. Plan and profile of district to be served by proposed sewers and disposal plant.

2. Plan and section of disposal plant. The village of Chadwicks is located on the D., L. & W. R. R. and Sauquoit creek about 7 miles south of Utica. The population of the village to be served by the proposed sewers and disposal plant is about 100. Outside privies are provided and it is not proposed at present to discharge excretal wastes into the sewer system. The sewage will, therefore, be chiefly sink and wash water which it is estimated will amount to about 1,200 gallons per day.

The proposed plans provide for permanent sewers to form part of a comprehensive sewer systein for the portion of the village north of Sauquoit creek, while the disposal plant is a temporary structure to be used until a larger proposed. disposal plant, to serve the entire sewer district which it is proposed later to form, is constructed.

The proposed sewer system is to consist of vitrified tile pipe from 6 to 8 inches in diameter. The proposed disposal plant will consist of a settling tank 5 x 10 feet in plan and 5 feet deep, giving a capacity of 1,875 gallons and a subsurface disposal field of about 400 feet of 4-inch tile pipe with open joints. The pipe is to be laid in about 19 parallel lines spaced 4 feet apart. The plans show only about 6 inches of cover, consisting of cobble stones, over the tile distributing pipe of the disposal field. This is not sufficient to prevent freezing and it is, therefore, recommended that over the 6 inches of cobble stones from 6 to 12 inches of soil be placed to prevent the field from freezing and also the sewage from rising to the surface and passing over ground to ditch. The effluent from the disposal piant will tiow into the waters of the State tributary to Sauquoit creek.

From our careful examination of the plans it would appear that the proposed sewer system and sewage disposal plant if properly constructed in accordance with the plans and the modifications suggested in this report should satisfactorily treat the sewage contributed to it.

I would, therefore, recommend that the plans be approved and that a permit be issued allowing the discharge of sewage from the proposed sewage disposal plant into the waters of the State tributary to Sauquoit creek and that the permit contain in addition to the usual revocation and modification clauses the following conditions:

1. That only sink and wash water and no excretal wastes, or storm or surface water from streets, roofs or other areas shall be admitted to the proposed sewers.

2. That the 6 inches of cobblestones or gravel over the tile pipe of the disposal field be covered with from 6 inches to 12 inches of soil to prevent freezing of sewage in pipes.

Respectfully submitted,
THEODORE HORTON,

Chief Engineer ALBANY, N. Y., September 11, 1917

PERMIT Application having been duly made to the State Commissioner of Health, as provided by section 76 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 Standard Silk Company of Chadwicks, Oneida "county, to discharge effluent from the sewage disposal works to be constructed by Standard Silk Company to treat sewage from their property into the waters of the State, tributary to Sauquoit creek at Chadwicks within the town of New Hartford 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 both the sewer systems and the sewage disposal works shown by plans approved this day shall be fully constructed in complete conformity with such plans except as amended by section 5 of this permit.

4. That only sink and wash water, and no excretal wastes or storm or surface water from streets, roofs or other areas shall be admitted to the proposed sewers.

5. That the 6 inches of cobblestones or gravel over the tile pipe of the disposal field be covered with from 6 to 12 inches of soil to prevent freezing of sewage in the pipes.

M. NICOLL, JR.,

Deputy State Commissioner of Health September 11, 1917

NEW ROCHELLE

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

I beg to submit the following report on our examination of plans for the disposal of sewage for the Burling Brook District of the city of New Rochelle, Westchester county, submitted to this Department for approval by the Department of Public Works of the city on April 27, 1917.

The sewerage conditions of the village and the actions taken by this Department in the past with reference to plans for sewerage and sewage disposal for the city of New Rochelle are covered fully in our report on examination of general plans for the disposal of sewage of the city dated December 29, 1914, and will, therefore, not be reviewed at this time except to state owing to the condition of pollution created by the discharge of sewage from the city and as the result of complaints of these conditions, the matter of providing satisfactory means for the collection and disposal of the sewage of the city has been taken up with the local authorities repeatedly during the past few years and they have also been advised that it would be necessary for this Department to defer action on further plans for sewer extensions pending the submission of satisfactory plans for sewage disposal.

The city of New Rochelle which has an area of approximately 3,200 acres is divided into four major sewer districts and, except for a relatively small district known as the “ Residence Park" district having an area of about 230 acres, the city is sewered on the separate plan. The sewage from the greater portion of the village comprising two sewer districts having a combined area of some 2,200 acres, is at present, discharged without treatment into Long Island Sound through a 24-inch pipe in deep water at a point near Bailey's Rock about 3,000 feet from the shore of the mainland. The sewage from the “Residence Park" district is discharged without treatment directly into New Rochelle creek, an arm of Long Island Sound, at the foot of Drake avenue extended.

The sewage from the greater portion of the Burling Brook district having an area of about 730 acres, is at present treated in a sewage disposal plant consisting of 5 chemical precipitation tanks located at Morgan street and known as the Morgan street plant. The effluent from this plant is discharged into comparatively shallow water of Long Island Sound near Glen Island. The sewage from a number of houses south of the disposal plant is discharged without treatment into the effluent pipe below the plant. The dry weather flow of sewage tributary to this disposal plant is claimed to be about 750,000 gallons per day and the wet weather flow is placed at 2,000,000 gallons per day. It is apparent that steps should be taken by the city to eliminate this large amount of storm or ground water which now reaches the sewers either by infiltration through the joints of the pipe or through storm water inlets or both.

The plans now submitted were prepared by Mr. James C. Harding, civil and sanitary engineer, New York City, and provide for the installation of a 1,000,000-gallon unit disposal plant to treat the sewage tributary to the present Morgan street plant at the site of this plant. According to the data submitted with the plans the proposed process of treatment called the

New Rochelle" process is the outcome of about one year of experiments carried out by Mr. Harding in conjunction with the city authorities at the Morgan sewage disposal plant and involves the filtration of the sewage through comparatively fine gravel with provisions for the aeration and cleaning of the filters.

Some 20 acres of land have been acquired by the city in the vicinity of the Morgan street plant to be used for sewage disposal and garbage incineration purposes and it appears from the data submitted with the present plans that if the proposed method of treating the sewage proves to be successful it is the intention of the city to install additional units of the proposed type of disposal and to intercept and convey the entire sanitary sewage of the city to the proposed site for disposal.

Sewage disposal works The proposed disposal works are to consist of a screening plant and 20 units of the so-called "New Rochelle ” filters with the necessary pumps, air compressors, blowers, valves and piping to operate the filters. The nominal capacity of the works is 1,000,000 gallons which is approximately equal to the flow treated at the present Morgan street plant.

Screening plant The proposed screening plant is to be located on the line of the present trunk sewer a short distance above the filters. The plans show both bar screens and a mechanical fine screen of the Riensch-Wurl type. According to the data submitted with the plans it is proposed to ask for bids on various types of screens. If bar screens are to be used it is proposed to install 4 screens having clear openings between the bars of from l-inch to 3/16-inch. If a mechanically operated fine screen is to be installed it is to have openings of 1/16-inch smallest dimensions.

Filters

Filters are to be formed by the reconstruction of 2 of the 5 present chemical precipitation tanks and are to be divided into 20 units il feet 8 inches long and 8 feet 3 inches wide each, giving a total superficial area of 1,930 square feet, equal to about .045 acres. The bottom of each filter is ·to be constructed with 12 parallel V-shaped troughs spaced about 1 foot center to center. In the bottom of each of these troughs is to be placed a 2-inch perforated air pipe connected with a 4-inch manifold air main which, according to the report of the designing engineer, is to connect with an air blower and an air compressor to be located in the operating-house. The filters are to be filled with gravel to a depth of about 3 feet The gravel in the troughs above the air pipes is to vary from 12 inch to 1 inch in size and the gravel above this layer is to vary from 14 to 12 inch in size.

The filters are to be provided with two 12-inch wrought iron influent pipes and two 12-inch wrought iron effluent pipes placed in a pipe gallery between the two groups of filters. A 4-inch lateral influent pipe

and a 4-inch lateral effluent pipe is to extend from the 12-inch mains to each filter and each of these 4-inch laterals is to be provided with a hydraulic valve. Each unit of the filter is also to be provided with three 2-inch wash water pipes to be connected with a 4-inch suction main leading to the wash water pump.

Three baffles are to be installed in each unit of the filter and these bafiles are to be so arranged as to cause the sewage to flow downward through the first section, upward through the second, downward through the third and upward through the fourth section of the filter. As noted above, the filters will have a superficial area of about .045 acres and will, therefore, be required to operate at the rate of from 16,000,000 to 44,000,000 gallons per acre per day, based on daily flows of from 750,000 gallons to 2,000,000 gallons per day.

Operation The method of operation of the works is quoted from the report of the designing engineer which is as follows:

"The sewage entering the plant from the present 24-inch inlet sewer will be passed through fine screens either mechanically operated and cleaned, or hand cleaned. In the former case screen openings will be 1/16 inch smallest dimensions, and in the other case will be 3/16 inch smallest dimensions. After passing through the screens the sewage will flow through the present channel to the two 12-inch inlet pipes in the filter galleries and from these will be discharged to the filters through 4-inch branches

controlled by hydraulically operated gate valves. The sewage on entering the filter will build up whatever head is required to allow it to pass to the outlet end of the filter, and depending of course, somewhat on the freedom of the filter from foreign matters. The sewage will pass downward in the first filter compartment, upward over a baffled wall in the second compartment, downward in the third and upward in the fourth compartment, from which it will be removed by a trough connected through a short 4-inch pipe to the 12-inch effluent line. This 4-inch pipe being controlled by a 4-inch hydraulically operated valve.

During the passage of the sewage through the filter, air will be admitted in sufficient quantities and as frequently as is found necessary, so that there will always be some oxygen at all places in the filter. From experiment with similar filters there has been no trouble experienced in shutting off the air for as long a period as one hour after aeration to a point where complete saturation of the sewage with oxygen was reached. In practice, however, it. is expected that air will be admitted for short intervals of time, say for 5 minutes, to each filter unit and will then be omitted for from 3 to 5 times the aerating period, or say perhaps 20 minutes.

At certain periods, as found necessary, the filters will be washed by admitting air through the air manifold at the bottom under high pressure and in sufficient quantity to thoroughly agitate the filter gravel at the same time forcing collected suspended matters to the top of the filter. With these coarse grained filters it is found that the air passing upward through the voids in the gravel act somewhat in the manner of air lifts, the bubbles of air carrying with them the suspended matters. To provide for the removal of this suspended matter, wash water pipes are introduced at the top of each section of each filter and these pipes are connected to a wash water pump to be located in the operating building. It is intended if fine screens, mechanically cleaned, are used to return this water to the sewer above the screen and remove the washed out suspended matters with the screenings. If this is not found to be satisfactory, it is proposed to return this wash water into a settling tank where the liquid can be removed and the easily settling out solids treated on drying beds in the same manner as is now treated the sludge from the mechanical precipitation works. The effluent from these works, if equal to that produced in the experimental plants, will be entirely clear, stable and with at least 95 per cent of the bacteria removed.

Conclusions and recommendations There is at present no plant of this type in operation for the treatment of sewage. The experimental plant at New Rochelle, which is not now in operation, was not visited by one of our representatives so that we have no first hand knowledge of its practicability and efficiency and the proposed plant, therefore, can not be considered other than in the light of an experiment. The plans, moreover, are somewhat general and certain details are lacking such as pumps, motors and piping. It appears also that the proposed method of disposing of the sludge from the filters has not been definitely determined upon, that is, as to whether it is to be returned to the screens and removed and disposed of with the screenings or discharged into settling tanks and removed to the sludge drying beds after settling. The method of disposal of sludge is an important question and should be given careful consideration. It is probable that some difficulty may also be experienced in effectively cleaning the filters with air alone, but it is understood that the designing engineer believes that these problems cannot be successfully worked out.

If the proposed plant will, in practice, continue to produce results comparable to those which seem to have been obtained at the experiment plant, the proposed plant should produce a satisfactory effluent and one that may be safely discharged into Long Island Sound without objection at this time. I can, therefore, see no objection to approving the plans for the proposed disposal plant with the understanding that it is in its experimental

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