[HISTORY: Adopted by the Town Board of the
Town of Wallkill 5-10-1990 by L.L. No. 6-1990. Amendments noted where
applicable.]
A.
Sewers shall be designed for capacity and flow in
accordance with the Recommended Standards for Sewage Works (Ten State
Standards).
B.
No gravity sewer conveying raw sewage shall be less
than eight inches in diameter.
C.
Sewers shall be laid true to line and grade with a
uniform slope between manholes. Sewers 24 inches or less shall be
laid with straight alignment between manholes.
D.
Manholes shall be installed at the end of each line;
at all changes in grade, size or alignment, at all pipe intersections;
and at distances not greater than 300 feet. A drop manhole, with an
exterior drop pipe, shall be constructed for a sewer entering a manhole
at an elevation of 24 inches or more above the manhole invert.
E.
Sewers shall be laid at least 10 feet horizontally
from any existing or proposed water main. The distance shall be measured
edge to edge. Sewers crossing water mains shall be laid to provide
a minimum vertical distance of 18 inches between the outside of the
water main and the outside of the sewer. The crossing shall be arranged
so that the sewer pipe joints will be equidistant and as far as possible
from the water main joints. Any deviation from the minimum horizontal
and vertical separation distances must be specifically approved by
the Orange County Department of Health.
F.
Prior to beginning the installation of sewers, the
developer shall submit to the Commissioner of Public Works or his
duly authorized representative the following items for review and
approval:
(1)
Sewer pipe cut sheets.
(2)
The manufacturer's shop drawing for sewer pipes.
(3)
The manufacturer's shop drawing for manholes.
(4)
The manufacturer's shop drawing for frames and covers.
The developer shall also submit to the Commissioner of Public Works
a projected schedule for sewer installation.
A.
Sanitary sewer pipe and fittings shall be polyvinyl
chloride pipe conforming to ASTM D3034, SDR 35, in sizes four inches
through 15 inches and ASTM F679, Type 1, SDR 35, in pipe sizes 18
inches through 27 inches. The joints shall meet the requirements of
ASTM D3212. Gaskets shall meet the requirements of ASTM F477.
B.
Manholes and bases, unless otherwise approved by the
Commissioner of Public Works, shall be precast reinforced concrete,
constructed in accordance with ASTM C478, latest revision. Precast
manhole barrels and cones shall be reinforced concrete with round
rubber gasketed joints conforming to ASTM C-361, latest revision.
C.
The outside faces of precast manholes shall be coated
with a bituminous waterproofing material.
D.
Invert channels shall be smooth and accurately shaped
to conform in shape and slope to that of the sewers.
E.
Precast manhole cone sections shall be constructed
with a twenty-four-inch diameter opening.
F.
No more than two lift holes may be cast or drilled
in each section. These lift holes shall be thoroughly plugged with
rubber plugs made specifically for this purpose.
G.
Manhole steps shall be extruded aluminum 6061-T6 alloy
with a drop front and safe tread or copolymer polypropylene conforming
to ASTM 2146-82, Type II, Grade 43758, with a one-half-inch-diameter
Grade 60 steel reinforcement.
H.
Manhole frames and covers shall be of iron castings
and shall be Campbell Foundry Pattern Number 1007C or equal. All manhole
covers shall have the inscription "Sewer" in letters three inches
tall and raised 1/16 inch.
I.
Sanitary sewer manholes shall be constructed to meet
the resilient connectors requirements of ASTM C-923.
J.
Built-in-place manholes may be constructed when approved
by the Commissioner of Public Works. Built-in-place manholes shall
be constructed of a poured concrete base, a minimum of eight inches
thick on a twelve-inch compacted gravel base, precast concrete manhole
blocks, cement sand mortar, aluminum steps and cast-iron frames and
covers.
K.
Built-in-place manholes shall be constructed only
when the temperature is above 32º F., and all work shall be protected
against freezing.
L.
The outside and inside faces of built-in-place manholes
shall be plastered and troweled smooth with 5/8 inch of mortar composed
of one part cement and two parts sand.
M.
The outside faces of built-in-place manholes shall
be coated with a bituminous waterproofing material.
N.
Manhole joints, brick work, and voids around penetrations are to
be sealed with nonshrink hydrolic cement/water plugs.
[Added 5-26-2016 by L.L.
No. 10-2016]
A.
All excavations for pipe shall be carried six or more inches deeper
than the final grade line of the pipe and then brought to grade line
with three-quarter-inch clean crushed stone. This three-quarter-inch
clean crushed stone shall have a width equal to the width of the trench
at the top of the pipe.
[Amended 5-26-2016 by L.L. No. 10-2016]
B.
The width of the trench at the top of the pipe shall
not exceed the diameter of the pipe plus 24 inches. Excavations for
manholes shall have a twelve-inch minimum and twenty-four-inch maximum
clearance on all sides.
C.
Materials such as peat or other soft material shall
be reported to the Commissioner of Public Works. In the event that
rock is encountered, excavation shall be carried eight inches below
the bottom of the pipe and gravel shall be used for backfill and tamped
thoroughly and rounded to receive pipe.
D.
The excavation of trenches shall be fully completed
a sufficient distance in advance of laying the pipe, but not more
than 50 feet unless permitted by the Commissioner of Public Works,
and the exposed end of all pipe shall be fully protected to prevent
earth or other substances from entering the pipe. The interior of
the pipe shall be carefully freed from all dirt or superfluous material
as the work progresses.
E.
The contractor shall remove, by pumping or other means,
any water accumulated in the excavation and keep the trench dewatered
until the bedding is complete.
F.
The contractor shall do all bracing, sheathing and
shoring necessary to perform and protect all excavation as required
for safety or to conform to governing laws.
A.
No pipes, manholes or other appurtenances shall be
backfilled until inspected and approved by the Commissioner of Public
Works or a duly authorized representative.
B.
Backfilling shall be done with approved material,
free from large stone or frozen earth.
C.
Immediately after pipes have been laid, backfilling shall commence.
The material surrounding the pipe, the pipe embedment zone, shall
be three-quarter-inch crushed stone carefully placed and thoroughly
compacted in such a manner that the line and grade of the pipe are
not disturbed. Backfill material shall be placed evenly and carefully
on both sides and over the pipe in six-inch lifts, and each lift shall
be thoroughly compacted until two feet of cover exists over the pipe.
[Amended 5-26-2016 by L.L. No. 10-2016]
D.
Where the pipe is installed in a utility easement
right-of-way, the trench above the pipe embedment zone may be backfilled
with material excavated from the trench, if approved by the Commissioner
of Public Works and the Superintendent of Sewer and Water. This backfill
shall contain no stones larger than eight inches in any dimension.
The backfill shall be placed in eight-inch lifts and thoroughly compacted.
This backfill will be carried to an elevation 12 inches below finished
grade. Four inches of run-of-bank gravel shall be placed on top of
the trench, covered by a layer of geotechnical fiber, Tensar SS1 Geogrid
or approved equal, covered by seven inches of well-graded DOT Type
2 or Type 4 material, covered by one inch of topsoil and sod.
E.
Where the pipe is installed in any paved area subject to vehicular
traffic, the entire trench (above the pipe embedment zone) shall be
backfilled to grade with NYSDOT Item 4, placed in eight-inch lifts
and thoroughly compacted.
[Amended 5-26-2016 by L.L. No. 10-2016]
A.
All pipe for service connections shall be of the same
class as the main sewer pipe and shall be capped with standard manufactured
plugs until ready for use.
B.
No pipe shall be cut for connections except when permitted
by the Commissioner of Public Works. Wyes, tees or saddles for service
connections shall be installed as required.
C.
The ends of pipe which enter masonry shall be neatly
cut to fit the inner face of the masonry. Joints shall not be covered
until duly authorized by the Commissioner of Public Works or his duly
authorized representative.
A.
The developer shall perform visual inspection and
testing of gravity lines. Test sections shall not exceed 500 linear
feet of interceptors, trunks or street mains, including house connections.
B.
The developer shall notify the Commissioner of Public
Works one week prior to the time the system or any part thereof is
ready for visual inspection and two weeks prior to the time the system
or any part thereof is ready for testing.
C.
Upon acceptance by the Commissioner of Public Works
of any corrections required from the visual inspection, the developer
shall perform an infiltration or exfiltration test. An infiltration
test shall be performed for those lines where the groundwater level
is a minimum of four feet higher than the top of the pipe. Where the
groundwater level is lower than four feet above the top of the pipe,
an exfiltration test shall be performed. Water testing or air testing
may be used for the exfiltration test.
D.
The rate of infiltration or exfiltration shall not
exceed 100 gallons per mile per 24 hours per inch of diameter of pipe.
The air test allows a minimum amount of time for air pressure inside
pipe to drop from 3.5 pounds per square inch gauge to 2.5 pounds per
square inch gauge. The allowable time is a function of the pipe size.
E.
The developer shall construct all bulkheads and provide
weirs or other means of measurement, pumps, water, plugs, fittings,
meters, lights, hoses and all else necessary for inspection and testing.
F.
When performing an infiltration test, the developer shall block off a section of the system not exceeding 500 linear feet and install a measuring device at the downstream end of the test section. Infiltration shall not exceed the allowable amount specified in Subsection D. If the actual infiltration exceeds the allowable infiltration or if there are visible signs of infiltration, such as gushing or spurting streams, the developer shall effect all repairs necessary to make the pipe sufficiently watertight. The section shall be retested until the rate of allowable infiltration is met.
G.
The water exfiltration test shall be performed between consecutive manholes, after water has been introduced into the section and all air expelled. A stabilization period shall be allowed for the absorption of water. The water level shall then be raised to two feet above the top of the pipe in the upstream manhole. The quantity of water required to maintain this level over a forty-eight-hour period shall be measured. Exfiltration shall not exceed the allowable as specified in Subsection D. If the actual exfiltration exceeds the allowable exfiltration or if there are visible signs of exfiltration from the pipe, the developer shall effect all repairs necessary to make the pipe sufficiently watertight. The section shall be retested until the rate of allowable exfiltration is met.
H.
Air testing.
(1)
Air testing may be used instead of the water exfiltration
test to measure exfiltration. The section to be tested shall be between
consecutive manholes. Each end of pipe and all branches, laterals
and wyes shall be plugged and securely braced. The plug at each end
of pipe shall have a provision to connect an air hose. Air shall be
supplied to the section and monitored so as not to exceed 5.0 pounds
per square inch gauge. The air pressure shall be maintained between
4.0 and 3.5 pounds per square inch gauge for at least two minutes
to allow the air temperature to come to an equilibrium with the pipe
walls. The air supply shall then be disconnected and the air pressure
allowed to decrease to 3.5 pounds per square inch gauge. At 3.5 pounds
per square inch gauge, the time shall be measured for the pressure
to drop to 2.5 pounds per square inch gauge. The following table shows
the allowable time for a loss of 1.0 pounds per square inch gauge
at an average pressure of 3.0 pounds per square inch gauge.
|
Pipe Size
(inches)
|
Allowable Time
(minutes: seconds)
| |
|---|---|---|
|
6
|
2:15
| |
|
8
|
3:57
| |
|
10
|
4:43
| |
|
12
|
5:40
| |
|
15
|
7:05
| |
|
18
|
8:30
| |
|
20
|
9:50
| |
|
24
|
11:20
| |
|
27
|
12:40
| |
|
30
|
14:30
| |
|
33
|
15:50
| |
|
36
|
17:10
|
|
TABLE I
| |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
MINIMUM SPECIFIED TIME REQUIRED FOR A 1.0 PSIG
PRESSURE DROP FOR SIZE AND LENGTH OF PIPE INDICATED FOR Q = 0.0015
| |||||||||||
|
1 Pipe Dia- meter
(inches)
|
2 Mini- mum Time (min: sec)
|
3 Length for Mini- mum Time
(feet)
|
4 Time for Longer Length
(second)
|
Specification Time for Length (L) Shown (min:sec)
| |||||||
|
100 feet
|
150 feet
|
200 feet
|
250 feet
|
300 feet
|
350 feet
|
400 feet
|
450 feet
| ||||
|
4
|
3:46
|
597
|
0.380 L
|
3:46
|
3:46
|
3:46
|
3:46
|
3:46
|
3:46
|
3:46
|
3:46
|
|
6
|
5:40
|
398
|
0.854 L
|
5:40
|
5:40
|
5:40
|
5:40
|
5:40
|
5:40
|
5:42
|
6:24
|
|
8
|
7:34
|
298
|
1.520 L
|
7:34
|
7:34
|
7:34
|
7:34
|
7:36
|
8:52
|
10:08
|
11:24
|
|
10
|
9:26
|
239
|
2.374 L
|
9:26
|
9:26
|
9:26
|
9:53
|
11:52
|
13:51
|
15:49
|
17:48
|
|
12
|
11:20
|
199
|
3.418 L
|
11:20
|
11:20
|
11:24
|
14:15
|
17:05
|
19:56
|
22:47
|
25:38
|
|
15
|
14:10
|
159
|
5.342 L
|
14:10
|
14:10
|
17:48
|
22:15
|
26:42
|
31:09
|
35:36
|
40:04
|
|
18
|
17:00
|
133
|
7.692 L
|
17:00
|
19:13
|
25:38
|
32:03
|
38:27
|
44:52
|
51:16
|
57:41
|
|
21
|
19:50
|
114
|
10.470 L
|
19:50
|
26:10
|
34:54
|
43:37
|
52:21
|
61:00
|
69:48
|
78:31
|
|
24
|
22:40
|
99
|
13.674 L
|
22:47
|
34:11
|
45:34
|
56:58
|
68:22
|
79:46
|
91:10
|
102:33
|
|
27
|
25:30
|
88
|
17.306 L
|
28:51
|
43:16
|
57:41
|
72:07
|
86:32
|
100:57
|
115:22
|
129:48
|
|
30
|
28:20
|
80
|
21.366 L
|
35:37
|
53:25
|
71:13
|
89:02
|
106:50
|
124:38
|
142:26
|
160:15
|
|
33
|
31:10
|
72
|
25.852 L
|
43:05
|
64:38
|
86:10
|
107:43
|
129:16
|
150:43
|
172:21
|
193:53
|
|
36
|
34:00
|
66
|
30.768 L
|
51:17
|
76:55
|
102:34
|
128:12
|
153:50
|
179:29
|
205:07
|
230:46
|
|
42
|
39:48
|
57
|
41.883 L
|
69:48
|
104:42
|
139:37
|
174:30
|
209:24
|
244:19
|
279:13
|
314:07
|
|
48
|
45:34
|
50
|
54.705 L
|
91:10
|
136:45
|
182:21
|
227:55
|
273:31
|
319:06
|
364:42
|
410:17
|
|
54
|
51:02
|
44
|
69.236 L
|
115:24
|
173:05
|
230:47
|
288:29
|
346:11
|
403:53
|
461:34
|
519:16
|
|
60
|
56:40
|
40
|
85.476 L
|
142:28
|
213:41
|
284:55
|
356:09
|
427:23
|
498:37
|
569:50
|
641:04
|
|
Note: If there has been no leakage (zero psig drop) after one
hour of testing, the test section shall be accepted and the test complete.
(See Section 7.5.)
|
(2)
If the actual time for a loss of 1.0 pounds per square
inch gauge is less than the allowable time shown on the above table,
the developer shall determine the source of leakage and effect all
repairs necessary to make the pipe sufficiently airtight. The section
shall be retested until the allowable time is met or exceeded.[1]
[1]
Editor’s Note: Former Subsection I, Final inspection,
which immediately followed, was repealed 5-26-2016 by L.L. No. 10-2016.
