USA > Massachusetts > Worcester County > Fitchburg > Address of the mayor, together with the annual reports for the city of Fitchburg, Massachusetts for the year .. > Part 31
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It has therefore been decided to construct one cast iron pipe siphon 30 inches in diameter and to build an overflow sewer from the siphon chamber to the Nashua river, to provide for the discharge of the surplus sewage delivered by the 48-inch out-fall in times of storm. The 30-inch siphon will have a capacity, under ordinary conditions, of about 11 million gallons per day, and under maximum conditions, as when the 48-inch intercepter is running full, it will have a capacity of about 12 million gallons per day. The velocity of flow through this siphon during ordinary dry weather, when the rate of sewage
1
593
REPORT OF, SEWAGE DISPOSAL COMMISSION
flow is from four to six million gallons per day, will be from 1.26 to 1.89 feet per second. While these velocities are ample for the maintenance of a clean pipe were the separate system already installed, it is probable that there will be more or less deposit of heavy gravel and sand during and immediately following severe storms, if provision is not made to intercept such mater- ials before they reach the siphon. For this reason, a grit chamber so designated as to retain only gravel and coarse sand, will be constructed upon the line of the intercepting sewer in the storage yard on Water street, recently purchased by the city. This will prove an advantageous location for a grit chamber as it can be conveniently inspected from time to time by employes of the department stationed at headquarters and it can be cleaned when necessary from within the storage yard.
As an additional precaution, a blow-off pipe, 30 inches in diameter, with necessary gate, will be provided at a point where the siphon crosses under the Nashua river. By opening the gate upon this blow-off pipe a velocity of flow of over eight feet per second can be maintained in the siphon in times of storm when sufficient storm water will be available and any sand or detritus which may have been deposited in it can thus be flushed out into the river. It will probably be necessary to use this blow-off, but rarely and only in times of storm when storm overflows into the river will be taking place throughout the city. A branch will be set in the 30-inch cast iron siphon near the intersection of Bemis and Falulah roads, with which can be connected a branch siphon to be laid in Bemis road and Summer street to a point near the intersection of Summer and Boutelle streets to serve districts No. 24 and No. 27.
At such time as the quantity of sewage is found to have increased sufficiently to overtax the 30-inch siphon, an addi- tional pipe can be laid between the siphon chamber and the disposal works. The size of pipe then laid will depend upon the probable future growth of the city. If it is then decided to make the same provision which is now planned for the future, this pipe will be 33 or 36 inches in diameter.
SECTION 2A. - This section of the intercepting sewer will extend to a point opposite the Arden Mill of the American Woolen Company, through the mill yard to and across the New
594
REPORT OF SEWAGE DISPOSAL COMMISSION
York, New Haven and Hartford Railroad location to Water street ; thence along Water street to the Sewer Department storage yard ; thence through said yard and across private land to Middle street ; thence from Middle street to and under the Nashua River, connecting with the lower end of Section 3. The maximum rate of sewage flow which this section, Station 62 +30- Station 91, must provide for, will be as follows : -
Quantity received from Section 3 37.17 c. f. s.
District No. 20
4.18 c. f. s.
District No. 21 24 c. f. s.
District No. 22 .67 c. f. s.
District No. 23
2.63 c. f. s.
Total 44.89 c. f. s.
The sewage from district No. 20, and probably from dis- tricts No. 21 and No. 22 will be discharged into the upper end of this section, while that from district No. 23 will be discharged into it at a point near Fifth street. The elevation of the upper end of Section 1 at Station 62+30 will be 398.1 and the eleva- tion of the upper end of Section 2a at Station 91 will be 406,- the total fall or slope being 7.90 feet equivalent to 1 in 363. A sewer 40 inches in diameter laid on this grade would have a capacity of 47.0 cubic feet per second, which would provide for the quantity of sewage likely to be tributary to this section. However, the borings indicated that ledge would be encount- ered between Stations 63+30 and 72 if this section of sewer were laid on a straight grade from its lower end to its upper end. It was, therefore, decided in order to avoid as much ex- cavation of ledge as possible, to increase the size to 48 inches in diameter, which if laid on a slope of one in one thousand will have a capacity of 46.3 cubic feet per second.
The sewer will be round and the velocity when flowing full, or half full will be 3.7 feet per second. It will be built of con- crete and where necessary will be reinforced with steel rods.
Between Stations 62+30 and 63+30 there will be a fall of 4.93 feet. When the sewer is running half full, or full, the sewage in this short section of 100 feet will have a velocity of 26 feet per second. This velocity is so high that there will be
595
REPORT OF SEWAGE DISPOSAL COMMISSION
danger of the erosion of the concrete invert and for this reason it will be protected by a vitrified brick lining.
From a point in the driveway of the Arden Mill to a point a short distance easterly of Fifth street, the sewer will be less than 20 feet in depth and will probably be constructed in open cut. From the upper end of this section to a point on the south bank of the Nashua river, the sewer will be laid at a depth of from 30 feet to 50 feet below the surface of the ground, and will be constructed in tunnel. From the northerly end of this tun- nel the sewer will be constructed across the Nashua river in trench, the top of the concrete structure being only slightly below the present bed of the river. The thickness of the con- crete where laid under the bed of the river, will be increased from 6 to 9 inches at the crown of the sewer and the structure will be reinforced with transverse and longitudinal steel bars.
From a point a short distance south of Fifth street to the southerly bank of the Nashua river, the sewer will be laid in tunnel through rock which it is believed will prove to be suffi- ciently sound and compact to make timbering of the tunnel un- necessary. Where the sewer is laid in rock tunnel and where timbering proves to be unnecessary, the thickness of the con- crete section may be reduced to 6 inches and will serve merely as a lining for the rock tunnel.
SECTION 3. - This section of the intercepter extends from a point near the north bank of the Nashua river about 250 feet east of Water street along the river and in private ways near the river, to Putnam street. The maximum ultimate rate of flow in this section is estimated to be as follows : -
Received from Section 4 28.89 c. f. s.
Received from District No. 15 4.77 c. f. s.
Received from District No. 16
2.77 c. f. s.
Received from Disirict No. 17 .15 c. f. s.
Received from District No. 18 .34 c. f. s.
Received from District No. 19 .25 c. f. s.
Total 37.17 c. f. s.
The total available fall between the upper and lowers ends of section 3 is 22.23 feet. The smallest sewer laid on a straight grade between the Nashua river near Water street and Putnam
596
REPORT OF SEWAGE DISPOSAL COMMISSION
street, which will provide for the maximum rate of flow, is 33 inches in diameter. Numerous borings along the line of the proposed sewer were made prior to the decision as to size and they indicated that fine running sand and ledge would be en- countered in the excavation, if the sewer were laid at a straight grade as suggested. Therefore it was finally decided to keep the sewer as high as possible and flatten the grade. This made it necessary to build a sewer 45 inches in diameter. It is prob- able, however, that the cost of this sewer was much less than would have been the cost of a 33-inch sewer laid at the greater deptlı, which would have been necessary if this sewer had been of this size. The minimum grade of the 45-inch sewer is one in one thousand, and the velocity of flow in it will be approxi- mately 3 feet per second when running full.
Between Stations 104+50 and 105, in the bed of the river, a short distance south of Laurel street, there is a fall in the grade of the sewer amounting to 1.6 feet, and between Stations 112 and 113 there is a fall in the grade of the sewer of 6.45 feet. At each of these places the velocity of flow will be so great as to cause serious wearing of a concrete invert, and for that rea- son this portion of the sewer invert is lined with vitrified brick.
The sewer is built, for the most part, of plain Portland ce- ment concrete, although portions of the structure are reinforced with transverse and longitudinal steel bars. Wherever the sew- er crosses in the river, or is laid in the bed of the river, the thickness of the concrete is increased, the crown thickness being increased from six to nine inches.
CONSTRUCTION IN 1911.
As soon as preliminary studies were sufficiently completed to make certain the size of the intercepting sewer it was deemed advisable to build some portion of the sewer during 1911. It being impossible to definitely settle the data relative to the main sewer at the disposal works until further studies were made relative to that phase of the sewerage problem, it was decided to attempt construction at first on that part of the sewer in the central portion of the city. The most feasible location with reference to speed in which plans and specifications could be prepared seemed to be that described below as Section 3 and
597
REPORT OF SEWAGE DISPOSAL COMMISSION
accordingly work preparatory to advertising for proposals was concentrated on that section.
SECTION 3, INTERCEPTING SEWER. This section is located between Station 91+00 at the Nashua river near the Dillon Steam Boiler Works and Station 120+27.66, a point 10 feet east of Putnam street. The size of the sewer is 45 inches cir- cular and the length is 2927.66 feet. The location was almost wholly in private land or in private passways, only about 190 feet, being in a public way, Water street. The material excavated was largely sand and gravel, excepting in the river bed where it was clay. Very little rock excavation was found outside much granite foundations of removed buildings west of Cushing street. Owing to the porous nature of the material and the depth below water level much ground water was encountered in the land of the J. Cushing estate, not only when crossing the river but also for considerable distances each side. About 900 feet of the excavation was handled with a cable-way, about 300 feet with a stiff leg derrick and about 830 feet with a Carson trench machine. The balance, being that part in the river bed, was excavated by hand and the material thrown to one side of the trench. The greatest depth of excavation to bottom of underdrain was 20 feet.
The standard section of sewer in this contract was built of plain concrete with a thickness of six inches at both invert and crown and about ten inches at springing line of the arch. Where the sewer was in the bed of the river or adjacent to the river there was such a probability of the seepage of a large amount of ground water that the thickness at the invert and crown was made nine inches and additional thickness added proportionally throughout the cross section. Reinforcing bars of twisted steel were also added to eliminate so far as possible the liability of seepage. In this contract a distance of 1250 feet was built with the thicker section and steel bars. For the
greater part of the sewer built in this contract the grade was one in 1000 which would give a maximum velocity of about 3.35 feet per second. Where there was such a change in grade as to greatly increase the velocity the invert was lined with a single course of vitrified brick. This was done for a distance of about 745 feet. The cement used on this contract was Lehigh.
598
REPORT OF SEWAGE DISPOSAL COMMISSION
Screened bank sand and screened gravel and broken granite were used for the concrete. All mixing was done by hand.
Proposals for this section were received July 11, 1911, and on July 13 the contract was awarded to the lowest bidder, McCarthy & Walsh of East Boston. Work was started at.once in assembling necessary equipment and actual excavation was begun July 26. The first concrete was placed August 11 and the last concrete on October 30. The contract called for com- pletion on November 15, 1911, and the work was completed a few days earlier.
Wooden forms were used for all concrete in this contract. The completed sewer is very smooth and will allow for a free flow of sewage fully as good as the best grade of brick work.
The following table gives the itemized proposals received July 11, 1911, for building Section 3 of the main intercepting sewer.
TABLE 9-MAIN INTERCEPTING SEWER, SECTION 3, BIDS RECEIVED JULY 11, 1911.
Item
Work and Material
Quantities
McCarthy & Walsh
East Boston, Mass.
Strueli & Puckhafer
Bridgeport, Conn.
Worcester, Mass.
C. E. Trumbull Co.
Joseph Long & Co.
Leominster, Mass.
Moore & Company
Boston, Mass.
Leominster, Mass.
Frank H. Cowin Co.
Boston, Mass.
Lowell, Mass.
la
Excavation and refilling trench Excavation and refilling trench Excavation and refilling trench Rock excavation in trench
1,250 lin. ft.
$7 90
$5 98
$10 58
$9 00
$8 30
$12 00
$14 50
$14 50
$7 25
1b
850 lin. ft.
5 64
6 40
5 42
5 50
5 10
9 50
10 50
12 00
40 00
1c
827.66 lin. ft.
8 34
6 25
10 56
10 00
8 80
12 00
15 00
14 50
10 00
2
50 cu. yds.
6 00
12 00
6 00
6 00
10 00
15 00
7 00
10 00
8 00
3
Brick masonry in invert
490 sq. yds.
2 50
3 12
2 25
2 50
12 00
3 50
5 00
3 00
3 35
4
Brick masonry in manholes
23 cu. yds.
15 00
10 35
16 00
15 00
18 00
16 00
17 00
20 00
19 00
5
Concrete masonry in trench
1,250 cu. yds.
8 00
10 51
8 44
10 00
11 50
13 00
14 50
15 00
12 00
6
Deformed steel bars
40,000 lbs.
0 025
0 06
0 03
0 04
0 05
0 04
0 05
0 06
0 05
Totals
$34,441 68
$35,992 23
$40,092 59
$40,171 60
$45,162 41
$53,689 92
$62,780 90
$63,906 07
$70,817 60
REPORT OF SEWAGE DISPOSAL COMMISSION
599
Connors Bros. Co.
.
Geo. W. Carr Co.
Boston, Mass.
Little & Seretto
600
REPORT OF SEWAGE DISPOSAL COMMISSION
The cost of section 3 of the main intercepting sewer includ- ing the amount payable to McCarthy & Walsh and the supplies furnished by the commission is shown in the following table :
TABLE 10. Total cost of Construction of Section 3, Main Intercepting Sewer
Item
Work and Material
Quantity
Unit Price
Total
la
Excavation and refilling trench
1.245 ft.
$7 90
$9.835 50
1b
Excavation and refilling trench
850 ft.
5 64
4.794 00
1c
Excavation and refilling trench
829 ft.
8 34
6,913 86
2
Rock excavation in trench
93 02 yds.
6 00
558 12
3
Brick masonry in invert
487.23 yds.
2 50
1,218 08
4
Brick masonry in man- holes
19.69 yds.
15 00
295 35
5
Concrete masonry in trench
1,287.62 yds.
8 00
10,300 96
6
Deformed steel bars
49,295.1 1bs.
025
1.232 38
7
Lumber left in place
85,168 ft. B. M.
15 00
1 277 58
8
Extra work
477 82
1
Total for Contractor
$36 903 59
Additional cost to city Pipe for underdrain, etc. Castings for manholes
428 60
107 33
Miscellaneous supplies
96 80
Total cost
$37,526 32
1
TRENCH EXCAVATION AT STATION 96 +00 WITH CABLE WAY
TRENCH EXCAVATION AT STATION 103+50 WITH STIFF LEG DERRICK
PLATE Il.
RIVER CROSSING AT STATION 104
SEWER TRENCH IN RIVER BED BELOW LAUREL, STREET ARCH BRIDGE
PLATE III.
-
BRACING IN 18-FOOT TRENCH NEAR STATION 112+40
WEIR AT STATION 93+00 TO ASCERTAIN GROUND WATER LEAKAGE. 45 INCH SEWER
PLATE IV
FINISHED SEWER IN RIVER BED NEAR CUSHING STREET BRIDGE
45 INCH SEWER AT STATION 111+70
PLATE V
RIVER CROSSING IN CUSHING POND AT STATION 116+50
WOODEN FORMS USED ON SECTION 3
PLATE VI.
BROWNELL- MASON CO ....
EXCAVATING WITH CARSON MACHINE AT STATION 114
SEWER TRENCH IN RIVER BED AT BOSTON AND MAINE RAILROAD
PLATE VII.
BRICK INVERT IN RIVER BED AT STATION 104+70
JUNCTION OF BRICK AND CONCRETE INVERTS AT STATION 113+00
PLATE VIII.
601
REPORT OF SEWAGE DISPOSAL COMMISSION
SECTION 2A. INTERCEPTING SEWER. This section is located between Station 62+30 in land of the American Woolen Co. and Station 91+00 at the southerly end of Section 3, a distance of 2870 feet. The location of the sewer for this section was first planned through land owned by the American Woolen Co., the Geo. W. Wheelwright Paper Co., and the Fitchburg Gas & Electric Light Co., and in the bed of the river, but early in the work on this location considerable opposition developed on the part of the owners of the land. Desiring to avoid dissatis- faction on the part of individuals or corporations which might lead to extended litigation other possible locations for the main sewer were considered between these termini. The most feasible alternate location seemed to be that finally adopted and described further on. The line through land owned by the corporations above named could have been built wholly by open trench work and so would have cost much less a linear foot to build and it seemed after much study to be the only satisfactory line without a tunnel. Comparing a tunnel location in Middle street with an open trench location on private land, the tunnel line was 720 feet shorter and much more expensive to build, yet it seemed probable that the additional length of line on private land with the damages to be paid for easements would more than make up for the more expensive tunnel construction. With this uncertainty it was decided to advertise for and receive proposals for both locations and leave the final adoption of the line until such proposals could be canvassed.
Proposals for these two locations were received August 15 and were as follows, Section 2 being the line on private land and Section 2A being the tunnel location in Middle street.
602
REPORT OF SEWAGE DISPOSAL COMMISSION
Item
Work and Material
Quantities
C. E. Trumbull Co.
A. G. Tomasello Co.,
Dorchester, Mass.
Leominster, Mass.
Worcester, Mass.
Somerville, Mass.
Dorchester, Mass.
Boston, Mass.
1a
Excavation and refilling trench,
1,590 lin. ft.
$3 70
$2 45
$3 06
$4 44
$3 50
$6 60
$9 00
1 b
Excavation and refilling trench,
845 lin. ft.
4 70
7 82
9 57
8 08
8 00
9 00
15 00
1c
Excavation and refilling trench,
573 lin. ft.
7 20
8 62
8 78
12 49
15 00
11 70
9 00
1d
Excavation and refilling trench,
582 lin. ft.
6 70
14 92
9 07
9 00
15 00
7 65
8 00
2
Rock excavation in trench,
1,029 cu. yds.
4 00
5 00
7 00
6 00
5 00
4 00
6 00
3
Earth excavation below grade,
600 cu. yds.
2 00
60
75
1 25
2 00
3 00
3 00
4
Gravel filling below grade,
750 cu. yds.
1 50
1 30
1 25
1 00
1 00
1 50
1 50
5
Earth filling in embankment,
4,550 cu. yds.
1 00
70
50
78
1 00
1 50
1 00
6
Brick masonry in invert,
84 sq. yds.
2 50
3 00
4 34
2 50
3 00
3 00
6 00
7
Brick masonry in manholes,
25 cu. yds.
15 00
16 00
17 00
15 00
16 00
15 00
20 00
8
Concrete masonry in trench,
9 00
10 25
11 00
11 82
10 50
10 00
10 00
9
Deformed steel bars,
05
047
04
03
04
0412
04
10
Channel for brook crossing. Station 61++-90
1
350 00
300 00
200 00
300 00
600 00
200 00
1,000 00
11
Extension of sewer. Station 60- 55,
1
100 00
75 00
65 00
61 50
150 00
70 00
200 00
12
Extension of sewer.
Station 58-165,
1
100 00
75 00
65 00
61 50
160 00
100 00
200 00
Totals
$46,709 50
$53,841 10
$54,503 79
$58,518 17
$61,352 00
$62,112 40
$70,557 00
Little & Seretto,
Geo. W. Carr Co.,
John J. Falvey,
James D. Kelley,
Coleman Brothers
Boston, Mass.
TABLE 11. Main Intercepting Sewer, Section 2. Bids received August 15, 1911.
-
1,560 cu. yds. 54,000 1bs.
REPORT OF SEWAGE DISPOSAL COMMISSION
TABLE 12
Main Intercepting Sewer, Section 2A. Bids received August 15, 1911.
Item
Work and Material
Quantities
Little & Seretto,
Leominster, Mass.
Dorchester, Mass.
A. G. Tomasello,
Coleman Brothers,
1a 1b
. Excavation and refilling trench Earth and rock tunnel Excavation and refilling trench Rock excavation in trench Brick masonry in invert Brick masonry in manholes Concrete masonry in trench Concrete masonry in tunnel and tun. manholes Deformed steel bars
1,220 lin. ft.
$6 84
$9 00
$6 75
$7 00
1,570 lin. ft.
15 85
17 50
23 75
37 50
1c
80 lin. ft.
15 50
15 00
20 00
20 00
2
850 cu. yds.
6 00
4 00
5 00
6 00
3
70 sq. yds.
4 34
3 00
3 00
6 00
4
10 cu. yds.
17 00
15 00
16 00
20 00
5
520 cu. yds.
11 00
10 00
9 00
10 00
6
650 cu. yds.
15 00
12 00
15 00
15 00
7
4,000 1bs.
04
041/2
041/2
04
8
Lumber left in place
70,000 ft. B.M.
20 00
30 00
15 00
25 00
$57,073 10
$58,695 00
$67,402 50
$91,595 00
Dorchester, Mass.
Boston, Mass.
James D. Kelley,
603
604
REPORT OF SEWAGE DISPOSAL COMMISSION
The canvass of these proposals showed a difference between the lowest bidders of $10,363.60 in favor of Section 2, but from the information gathered at interviews with the representatives of these corporations it was believed that the construction of the tunnel line would result in a less total expenditure. Finally it was decided to build on the tunnel location and on August 25 the contract was awarded to Little & Seretto, the lowest bidders.
This section is located on the land of the American Woolen Company and the location of the New York, New Haven & Hartford Railroad Company from Station 62+30 to Station 64+49; in Water street from Station 64+49 to Station 67+96 ; on land of the city from Station 67+96 to Station 72+44; on land of the New York, New Haven & Hartford Railroad Com- pany from Station 72+44 to Station 75+18; in Middle street from Station 75+18 to Station 89+27 and in private land and in the river bed from Station 89+27 to Station 91+00.
Borings taken on this location indicated that rock excava- tion of varying depths would be necessary on nearly the whole length of the section and the depth in Middle street would be so great that a tunnel would be more economical than open trench. The plans and specifications were made with the expectation that about 1570 feet of this contract would be in tunnel and the balance of 1300 feet would be in open trench. So far as work has been done on this contract the material excavated outside of filled land has been clay and rock. The rock is not dense but is much broken both as to strata and in each stratum. These strata lay at an angle of about 30° from horizontal. The greatest depth of excavation in open trench is about 30 feet and the greatest depth of sewer invert in tunnel below the surface of Middle street is 43.5 feet.
The excavation and construction on the open trench work has been handled with a Carson trench machine. On the tunnel and shafts the excavated material and concrete will be taken from and lowered into place in buckets by a stationary hoisting engine and stiff leg derrick. An air compressor is being installed for operating the power drills in the tunnel and the tunnel will be lighted with electricity.
The finished sewer on this contract is to be 48 inches in diameter and for all but 100 feet the grade is one in 1000.
-
PLATE IX
MAIN ST|
HER
SECTION 3
LUNENBURG
FITCHBURG
FILTRATION
CHUJA
NASHUA
SIPHON
CHAMBER
NASHUA
RIVER
WAT
NYNHOHER
NEWTON
PLAN
460
3
450
440
NYNHANAK
Gris Chamber
Primary Dans
Spanking Filter
Secondary tante
Sand Dvd's
Cutter
170
410
400
300
370
150
140
Section 3
Section ?A
- 40" Diameter-Concreto
30' Diameter-Cast Iron Pipe
120
55
50
45
40
30
25
15
$
0
.
PROFILE
1
-
SECTION IN RIVER BED
Earth Ledge TYPICAL SECTION
JECTION IN TUNNEL
40' DIAMETER
SCALE OF SECTIONS
Scak of Feet
City of Fitchburg Sewage Disposal Commission
MAIN INTERCEPTING SEWER-SECTIONS 1,2A,3,4.
PLAN AND PROFILE
SCALES
VERTICAL
HORIZONTAL
SCALE OF FEEY
SCALE OF FECT
1911.
Sheet No 2
400
Tunnel
30
150
150
340
Sechon /
330
-45 Diameter-Concreto
150
145
140
135
130
170
115
105
100
80
75
10
65
60
BOSTON A MAINDIR R
INTERVALE
HOAD
TALULAH
AREA
30'
NSON ST.
FITCHBURG
LEOMINSTER
Legend-
completed trunk sener - trunk pemir under contract
..... proposed trunk sener
sener outlets
15
-
FUTURE
SECTION OF SIPHON CAST IRON PIPE
TYPICAL SECTION
45"DIAMETER
DAY ST
WATER
MAIN
FIR
SPRU
RIVER
BOSTON & M
140
605
REPORT OF SEWAGE DISPOSAL COMMISSION
The standard section in open trench is six inches of con- crete at both invert and crown and 1012 inches at springing line of the arch. In the tunnel the minimum allowable thickness of concrete is six inches.
All concrete for this section of sewer is mixed one part cement, two and one-half parts sand and four and one-half parts broken stone or screened sand. The brand of cement used is Giant. The mixing of concrete is being done by hand. Blaw steel forms are being used.
The contract for this section was awarded August 25 and the first excavation was made September 21. To January 1 about 600 feet of sewer in trench had been completed. The tunnel shaft at Fourth street had been excavated to grade and headings started from this shaft, and the shaft near Second street had been excavated to a depth of about 15 feet. The contract calls for completion by July 15, 1912.
SECTION 1. INTERCEPTING SEWER. - This section will extend from Station 2+30 on the high land at the disposal area to Station 62+30 at the southerly terminus of Section 2A, a distance of 6000 feet. About 900 feet of this will be a 48 inch concrete sewer on a grade of 1 in 1000, and the balance will be a 30 inch cast iron pipe siphon. The pressure at the lowest point on the siphon will be about 23 pounds per square inch. The completed siphon line will consist of a 30 inch and a 36 inch line in order to equal the capacity of the 48 inch sewer but only the 30 inch line will be laid at present. At the junction of the 48 inch sewer and the siphon line will be constructed a siphon chamber with an overflow to the mill pond of the Duck Mill Company. This overflow will only come into use when the flow is in excess of the capacity of the 30 inch siphon and for a number of years this will only be at times of heavy rain or rapidly melting snow. The cast iron pipe for this section will probably be delivered during the winter so that an early be- ginning of this work can be made. Plans for this section are about completed so that it will be possible to award the contract for construction early next season.
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