New sanitary sewers and all extensions to sanitary sewers owned
and operated by the Village shall be designed, by a professional licensed
to practice sewer design in the state, in accordance with the Recommended
Standards for Sewage Works, as adopted by the Great Lakes-Upper Mississippi
River Board of State Sanitary Engineers (10 States Standards), and
in strict conformance with all requirements of the NYSDEC. Plans and
specifications shall be submitted to, and written approval shall be
obtained from, the Superintendent and the NYSDEC before initiating
any construction. The design shall anticipate and allow for flows
from all possible future extensions or developments within the immediate
drainage area.
Plans, specifications, and methods of installation shall conform
to the requirements of this article. Components and materials of wastewater
facilities not covered in this chapter, such as pumping stations,
lift stations, or force mains shall be designed in accordance with
Section 501 and shall be clearly shown and detailed on the plans and
specifications submitted for approval. Additional force main details
are covered in Section 505. When requested, the applicant shall submit to the Superintendent
all design calculations and other pertinent data to supplement review
of the plans and specifications. Results of manufacturer's tests on
each lot of pipe delivered to the job site shall also be furnished
upon request.
Sewer pipe material shall be:
A. Polyvinyl chloride (PVC) pipe, standard dimension ratio (SDR) 35,
minimum.
(1) Pipe shall be made from Class 12454-B materials or better in accordance
with ANSI/ASTM Specification D1784.
(2) Pipe and accessories shall conform to the requirements of the following
with a minimum pipe stiffness of 46 psi at a maximum deflection of
5%:
ANSI/ASTM D 3034 (4 inches to 15 inches)
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ASTM F679 (18 inches to 27 inches)
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B. Ductile iron pipe.
(1) Pipe, fittings, and specials shall be manufactured in accordance
with ASTM Specification A746. Pipe shall have a minimum thickness
of Class 50.
(2) Fittings shall conform to ANSI Specification A21.11 and have a minimum
pressure class rating of 150 psi.
(3) All pipe and fittings shall be cement mortar lined in accordance
with ANSI Specification A21.4 at twice the specified thickness, and
have an internal and external bituminous seal coating.
(4) Closure pieces shall be jointed by means of a mechanical coupling
of the cast-sleeve type.
C. Other pipe materials. Other pipe materials require prior written
approval of the Superintendent before being installed.
D. The minimum internal pipe diameter shall be eight inches.
E. Joints for the selected pipe shall be designed and manufactured such
that O-ring gaskets of the snap-on type are used.
F. Gaskets shall be continuous, solid, natural or synthetic rubber,
and shall provide a positive compression seal in the assembled joint,
such that the requirements of Section 504 are met.
G. Joint preparation and assembly shall be in accordance with the manufacturer's
five recommendations.
H. Wye branch fittings shall be installed, for connection of street
laterals, in accordance with Section 506.
All sanitary sewers or extensions to sanitary sewers, including
manholes, shall satisfy requirements of a final infiltration test
before they will be approved and wastewater flow permitted by the
Village. The infiltration rate shall not exceed 25 gallons per 24
hours per mile per nominal diameter in inches. An exfiltration test
may be substituted for the infiltration test; the same rate shall
not be exceeded. The exfiltration test shall be performed by the applicant,
under the supervision of the Superintendent, who shall have the responsibility
for making proper and accurate measurements required. The exfiltration
test consists of filling the pipe with water to provide a head of
at least five feet above the top of the pipe or five feet above groundwater,
whichever is higher, at the highest point under test, and then measuring
the loss of water, from the pipe section under test, by the amount
of water which must be added to maintain the original level. In this
test, the test section must remain filled with water for at least
24 hours prior to taking any measurements. Exfiltration shall be measured
by the drop of water level in a standpipe with a closed bottom end
or in one of the sewer manholes serving the test section. When a standpipe
and plug arrangement is used in the upper manhole in the test section,
there shall be some positive method for releasing entrapped air prior
to taking any measurements.
The test section shall be as ordered or as approved, but in
no event longer than 1,000 feet. In the case of sewers laid on steep
grades, the test length may be limited by the maximum allowable internal
pressure on the pipe and joints at the lower end of the test section.
For purposes of determining the leakage rate of the test section,
manholes shall be considered as sections of forty-eight-inch-diameter
pipe, five feet long. The maximum allowable leakage rate for such
a section is 1.1 gallons per 24 hours. If leakage exceeds the allowable
rate, then necessary repairs or replacements shall be made, and the
section retested.
The test period, during which the test measurements are taken,
shall not be less than two hours.
Prior to testing, the section shall be lamped. Any joint out
of straight alignment shall be realigned.
Also prior to testing, any plastic pipe, in the test section,
shall be tested for deflection. Deflection testing shall involve the
pulling of a ball, whose diameter is 95% of the pipe inside diameter,
through the pipe. Any joint with a deflection greater than 5% shall
be replaced. The test section shall be flushed just prior to deflection
testing.
Force mains serving sewage lifting devices, such as grinder pumps and pump stations, shall be designed in accordance with §
105-23. Additional design requirements are:
A. Trenching, bedding, and backfilling shall be accordance with §
105-25.
B. Drain valves shall be placed at low points.
C. Automatic air relief valves shall be placed at high points and at
400-foot intervals on level force main runs.
D. Air relief and drain valves shall be suitably protected from freezing.
E. When the daily average design detention time, in the force main,
exceeds 20 minutes, the manhole and sewer line receiving the force
main discharge or the sewage shall be treated so that corrosion of
the manhole and the exiting line are prevented. The corrosion is caused
by sulfuric acid biochemically produced from hydrogen sulfide anaerobically
produced in the force main.
All sanitary sewers and extensions to sanitary sewers constructed
at the applicant's expense, after final approval and acceptance by
the Superintendent, and concurrence by the Village Board, shall become
the property of the Village, and shall thereafter be operated and
maintained by the Village. Said sewers, after their acceptance by
the Village, shall be guaranteed against defects in materials or workmanship
for one year, by the applicant. The guarantee shall be in such form
and contain such provision as deemed necessary by the Village Board,
secured by a surety bond or such other security as the Village Board
may approve.