New sanitary sewers and all extensions to sanitary
sewers owned and operated by the town 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 ("Ten
State 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, the Town
Planning Board 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 Part
2. Components and materials of wastewater facilities not covered in this Part
2, such as pumping stations, lift stations or force mains, shall be designed in accordance with §
132-27 and shall be clearly shown and detailed on the plans and specifications submitted for approval. Additional force main details are covered in §
132-40. When requested, the applicant shall submit, to the Superintendent and to the Town Planning Board, 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.
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 town. 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 the 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, all 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 §
132-27. Additional design requirements are:
A. Trenching, bedding and backfilling shall be in accordance with §
132-32.
B. Drain valves shall be placed at low points.
C. Automatic air-relief valves shall be placed at high
points and at four-hundred-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 Town Board,
shall become the property of the town and shall thereafter be operated
and maintained by the town. Said sewers, after their acceptance by
the town, shall be guaranteed against defects in materials or workmanship
for one year by the applicant. The guaranty shall be in such form
and contain such provision as deemed necessary by the Town Board,
secured by a surety bond or such other security as the Town Board
may approve.