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the plants would satisfactorily perform the functions for which they were intended.

During the year 1917 plans for sewerage and sewage disposal systems or for extensions or modifications to existing systems. have been examined and approved in connection with the following places and in each case a report setting forth the results of the examination of the plans and the essential features of the design has been prepared:

ALBION (Orleans County Home)

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

I beg to submit the following report on an examination of plans for sewage disposal for the Orleans County Home at Albion, Orleans County, N. Y., submitted to this Department for approval by the Board of Supervisors on August 18, 1917.

The Orleans County Home is located on level ground about 14 miles south of the village of Albion. The total population of the home is generally about 125 people.

The plans for the disposal of the sewage from the home now submitted to this Department for approval contemplate the construction of a sewage disposal plant consisting of a sedimentation tank, a dosing chamber and sand filters, located about 300 feet east of the main building. According to the general layout submitted with the plans of the plant the wells from which the institution takes its water supply appear to be located above and at a sufficient distance from the plant to be safe from contamination either by seepage from the plant itself or from the sewer line leading to the plant.

The sedimentation tank is a closed concrete structure divided into two sections by a longitudinal division wall. Baffles are provided near both the inlet and outlet ends to prevent unnecessary disturbance of the contents and the escape of scum over the outlet weir. Each section of the tank has a capacity of 3,200 gallons, making the average detention period with an assumed sewage flow of 100 gallons per capita per day and with both tanks in use, of about 12 hours. A diverting chamber is provided near the inlet end of the tank so that either section may be used without the other. No provision is made for the removal or discharge of the sludge which will accumulate in the tank. A manhole is provided in the top of each section and it is assumed that the tank will be cleaned by hand at intervals and the sludge disposed of by application to the soil at some part of the grounds remote from the building and from the stream or ditch which receives the natural drainage of the property.

Adjoining the sedimentation tank is a dosing chamber of 800 gallons capacity, the equivalent of about 12 hours' average flow. This tank is fitted with two 5-inch alternating siphons, arranged to discharge the effluent from the sedimentation tank into the sand filters. The quantity discharged at each dose will be equivalent to a depth of about % of an inch over the surface of one sand bed.

The sand filters consist of three beds of equal size. Each bed has an area of 0.038 of an acre, making the total area 0.113 of an acre. Figured on the basis of the total area the average rate of filtration will be 110,000 gallons per acre per day, a rate somewhat in excess of that desirable for sand filters to be operated under the conditions existing at Albion. Plants of this type to be operated under these conditions should be designed to provide sufficient area of sand to give a rate of filtration of not over 80,000 gallons per acre per day. The proposed beds are to be built of 6 inches of small field stone, 6 inches of 12 to 4-inch screened gravel and 24 inches of clean sharp sand.

The effective size of the sand is not given but it would seem desirable that it should be kept between 0.20 and 0.35 mm. The arrangement of the alternating siphons and of the diverting gates at the sand filters is such that it allows any two of the sand beds to be used at one time, but requires that one bed always remain idle. The sewage is distributed on the beds by wooden troughs, and the effluent collected by tile underdrains laid in broken stone at the bottom of the beds, and discharged into a small ditch which receives the natural drainage from the institution grounds.

This ditch is a tributary of the west branch of Sandy creek, a stream which flows through the village of Albion and empties into Lake Ontario near North Hamlin. No data is furnished regarding the flow of this stream, but the area of the watershed above the village is about 10 square miles. The effluent from the proposed plant will be discharged into the stream at a point 2 miles above the village.

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 and a permit issued for the discharge of the effluent from the sewage disposal plant into a stream on the property of the home in the town of Albion, tributary to Sandy creek on the following conditions:

1. That the area of the sand beds be increased so that the rate of filtration based on an average flow of 100 gallons per capita per day will not be in excess of 80,000 gallons per acre per day.

2. That the layer of sand comprising the filtering material of each of the proposed filter beds shall be not less than 30 inches deep.

3. That the effective size of the sand used in the filter beds be not less than 0.20 mm. or greater than 0.40 mm.

Respectfully submitted,

ALBANY, N. Y., November 7, 1917

THEODORE HORTON,

Chief Engineer

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 the Board of Supervisors of Orleans county to discharge effluent from the proposed sewage disposal works at the Orleans County Home into the waters of West Branch Sandy creek at the point of discharge shown by the plans within the town of Albion 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 the sewage disposal plant shown by the plans approved this day shall be fully constructed in complete conformity with such plans or approved amendments thereof except as stated in conditions 6 and 7 of this permit.

4. That only sanitary or domestic sewage and no storm water from roofs or other areas shall be admitted to the proposed sewage disposal plant.

5. That no sewage sludge from any part of the disposal plant shall be discharged into West Branch Sandy creek or any other body of water.

6. That the area of the sand filter beds shall be so increased that the rate of filtration, based on an average flow of 100 gallons per acre per day, will not exceed 80,000 gallons per acre per day.

7. That the layer of sand comprising the filtering material of each of the proposed filter beds shall not be less than 30 inches deep.

8. That the effective size of the sand used in the filter beds shall be not less than 0.20 mm. and not greater than 0.40 mm.

M. NICOLL, Jr.,

Deputy State Commissioner of Health

November 10, 1917

ALTAMONT

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

I beg to submit the following report on our examination of the plans for a sewerage system and sewage disposal plant of the village of Altamont, Albany county, submitted to this Department for approval by the trustees of the village on August 27, 1917.

The records of this Department show that plans for a sewerage system and sewage disposal plant consisting of septic tanks and contact beds, were approved by the Department on August 19, 1907. In 1912 an engineer of this Department, at the request of the village trustees, investigated certain insanitary conditions existing in the village and reported under date of June 4, 1912, that no portion of the system for which plans were approved on August 19, 1907, had been constructed but that two 12-inch storm sewers had been built on Main street. He further reported that several houses in the village were provided with cesspools, or septic tanks, and that the effluent from these tanks was being discharged in the ditches and into the 12-inch storm sewers resulting in the occurrence of serious local nuisances at several points.

No steps were taken, however, to abate these nuisances and on June 29, 1916, the Board of Health of Altamont was directed by the Deputy State Commissioner of Health in accordance with section 26 of article 3 of the Public Health Law, to take action to abate the nuisance on Lark street, Main street and Lincoln avenue, caused by the overflow from septic tanks and cesspools into the street gutters and into streams which flow across the streets. The Board of Health failed to abate the nuisance and the matter was turned over to the Attorney-General who applied to the Supreme Court for a writ of mandamus. The date set for the argument of the case was July 21, 1917. On July 18 word was received by this Department that the village trustees had engaged an engineer to prepare plans for a sewerage system and sewage disposal works for the village. In view of this fact an adjournment was granted by the Attorney-General. The plans were prepared, and have now been submitted to this Department for approval.

The sewerage system shown on the plans is a comprehensive system designed to serve the entire village. It is proposed to incorporate in the system the two existing 12-inch sewers on Main street which the engineer reports are in good condition. These sewers are now used to carry storm water but it is intended to disconnect all pipes conducting storm water to these lines, and to carry the storm water in the gutters or in new storm sewers to be constructed later if necessary. The pipes comprising the sewer system vary in size from 8 to 12 inches and are of ample capacity to serve the present population of 800, or any future population that may be reasonably expected to be reached. The grades are in general steep enough to give self-cleansing velocities.

Manholes are provided at intervals of less than 400 feet over the entire system and with the exception of two points on the old 12-inch lines there is no break in the grade or alignment between manholes. The two points mentioned are on Main street between Park place and Lincoln avenue, where the present sewers are laid on curves. The grades. however, are steep and the manholes are close together so that little trouble should be experienced in keeping the sewers in good condition.

At one point on the 12-inch trunk between the village and the disposal works the line passes very close to a spring which it is intended to use at some future time as sources of water supply for the village. Although the spring is on the opposite side of a stream from the sewer, it would seem desirable to construct the trunk line of cast iron pipes with lead joints for a distance of at least 100 feet on each side of the spring.

It is intended to construct, at the present time, only the lines on Lincoln avenue and Lark street and the trunk sewer together with such short section as may be necessary to connect these lines to the present sewers. The present population that this portion of the system will serve is estimated at approximately 250 people.

The proposed sewage disposal plant is to be located on the west bank of the Bozen Kill about 2 mile east of the village and consists of an Imhoff tank, sprinkling filter, chlorination plant, final settling tank and sludge drying bed. The works are designed by the engineer to serve a population of 400 people and arranged in units so that extensions may be made as more houses are connected to the sewers. The estimated flow used by the engineer in designing the plant was 100 gallons per capita per day.

The Imhoff tank is of such size as to give an average detention period of 3 hours in the upper compartment, and to provide a sludge storage capacity of 1 cubic foot per capita in the lower compartment. The velocity through the settling compartment will be 1.7 inches per minute. Eight-inch cast iron draw-off pipes are provided to conduct the sludge to the sludge bed. A concrete dosing tank of 600 gallons capacity or about 20 minutes' average flow, equipped with a 5-inch siphon, is located at the lower end of the tank to receive the effluent. This siphon, while it is large enough to care for the average flow of some 400 people under the head provided, is a little too small to handle satisfactorily the maximum flow that may be received at the plant before additional units are constructed. Its capacity is not as great as the capacity of the rest of the plant. In view of the above facts and of the fact that the cost of 6-inch siphon is only slightly greater than that of the proposed size, it would seem advisable to install a larger siphon. The siphon will discharge the contents of the dosing chamber through 6-inch and 4-inch cast-iron distributors and risers to the nozzle of the sprinkling filter.

This filter has an area of 1,650 square feet and an average depth of 4 feet, 9 inches. The filtering material is to be broken stone from 1 inch to 2 inches in diameter. With the assumed population of 400 people and a flow of 100 gallons per capita per day the operating rate of the filter will be 1 million gallons per acre per day or 220,000 gallons per acre per day per foot of depth. The sprinkler nozzles are set 13 feet on centers and will operate at a head of from 6 feet 6 inches to 1 foot 6 inches. The concrete floor of the bed is covered with 6-inch split tile and drains to a trough at one side from which the effluent flows through a 12-inch tile pipe to the chlorinating tanks.

The engineer's report does not give any information as to the capacity of the chlorinating apparatus or the quantity of chlorine that is to be applied to the filter effluent. In view of the fact that the stream into which the effluent will be discharged is the proposed new source of water supply for the city of Watervliet, it would seem advisable that chlorine should be applied at the rate of not less than 10 parts per million and that the apparatus installed should be of sufficient capacity to allow of the application of chlorine at a rate somewhat in excess of this. The final settling tanks through which the sewage passes after chlorination are of concrete and have a combined capacity of 2,000 gallons. giving a detention period of 14 hours with both tanks in use. A 12-inch tile pipe conducts the effluent from the chlorination tank or final settling tank to the Bozen Kill. No means are indicated on the plans for removing the sludge from the chlorination tanks, but the engineer's report states that it is intended to pump it out by hand and dry it on the sludge bed.

The area of the sludge bed is 225 square feet providing about 0.13 of an acre of surface per 1 million gallons average flow. The bed is 12 inches thick at the outside edges and 20 inches thick at the center. It is built of 4 layers of stone and sand varying in size from 21⁄2-inch stone on the bottom to a

medium sand on the top. The sludge is discharged on the bed from 2 8-inch inlets located at the upper end. No provision is made for preventing the incoming sludge from cutting through the sand and finding a direct passage in the under drains. It would seem advisable to provide some form of aprons at the inlets to prevent this from occurring. The sludge bed is underdrained by 4-inch tile 3 feet, 9 inches on centers and the effluent from the underdrains is to be collected by a main drain and conducted to the chlorination tanks. The plant is set at such an elevation that part of the land used in connection with it will be below extreme high water level, as indicated on the plans, and the floor of the sprinkling filter will be covered by 2 feet of water during the flood periods. The tops of all the tanks and of the sludge bed embankment are, however, above maximum high water level and since the periods of extreme high water occur at infrequent intervals, the conditions while undesirable, will not interfere seriously with the operation of the plant. It would seem advisable, however, in view of the above facts to arrange the plant so that the elevation of the floor of the filter will be above high water. An embankment is shown on the plans surrounding the entire plant and evidently intended to protect it from high water. This embankment is unnecessarily high, the top elevation being 8 feet above high water. It does not seem to be protected in any manner from the wash of the stream. The area enclosed by the embankment is not drained and is so arranged that it forms a basin in which water from the adjacent hill will collect. Some provision should be made for preventing the run off from this hill from entering the basin, and if found necessary drains should be provided through the embankment fitted with flat valves to prevent the water of the stream from backing into the enclosure.

In view of the results of our examination of these plans and after careful consideration of the essential features of the design, and local and general requirements with respect to the proper methods of disposal of sewage from the proposed system, I beg to recommend that these plans be approved and a permit be issued allowing the discharge of effluent from the proposed sewage disposal plant into the Bozen Kill in the town of Guilderland on the following conditions:

1. That before the spring near the proposed sewage disposal plant is used as a source of water supply for the village, the tile sewer for 100 feet on each side of it shall be replaced by a sewer of cast-iron pipe laid with lead joints.

2. That aprons be provided on the sludge bed to prevent the incoming sludge from cutting through the bed and finding a direct passage to the underdrains.

3. That the size of the siphon in the dosing chamber be increased to not less than 6 inches.

4. That the chlorinating apparatus installed have sufficient capacity to allow the application of chlorine at the rate of 15 pounds per day.

5. That the plant be so arranged that the floor of the filter will be above extreme high water.

6. That chlorine be applied to the effluent from the plant at all times at the rate of not less than 10 parts per million.

7. That an additional unit of the disposal plant be constructed and put in operation before the flow of sewage reaching the plant has increased materially above that contributed by 600 persons.

Respectfully submitted,

ALBANY, N. Y., September 5, 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

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