The minimum earth cover over the top of the
water main pipe shall be four feet six inches.
Concrete thrust blocks and approved mechanical
restraints shall be provided at all tees, bends, plugs, pipe ends
and hydrants to firmly support the pipe and to prevent the pipe from
shifting out of alignment. The thrust block shall bear on undisturbed
ground at the side of the trench. The size of thrust blocks shall
be calculated by standard engineering design methods and approved
by the Town Board.
Line valves shall be located at each street
intersection in such a manner that each block of each street can be
isolated from the system by closing no more than two valves. Valves
shall be placed so that the distance between valves will not exceed
1,000 feet.
No one, except an employee of the Town of Seneca
Falls Water Department, shall operate any water main valves within
the water service area of the Town of Seneca Falls.
All new mains, before they are put in service,
shall be flushed with enough velocity to assure that all dirt, sand,
gravel, etc., is thoroughly washed out of the section of main.
After testing as outlined above, all sections
of water main, including hydrants and hydrant branch lines, shall
be sterilized using the following procedure:
A. The section to be sterilized shall be completely isolated
from the rest of the water system by closed valves.
B. A tap shall be made in the main adjacent to the valve
through which the flow of water is to be admitted to the section of
main to be sterilized for the purpose of injecting chlorine or hypochlorite
solution. If a hydrant is not available at the far end of the section
to be sterilized, a second tap shall be made at the end of the line
to discharge water during the sterilizing procedure.
C. The valve controlling the water from the water system
shall be opened and the hydrant or tap at the end of the line shall
be opened. Either liquid chlorine or hypochlorite solution shall be
injected into this flow of water in such a concentration as to give
a minimum chlorine residual in the new main of 50 parts per million
and a maximum chlorine residual of 100 parts per million. The new
main shall be completely filled with this chlorinated water for 24
hours. At the end of 24 hours, the chlorine residual must be at least
25 parts per million or the sterilization procedure must be repeated.
D. At the end of 24 hours, the chlorinated water shall
be flushed from the mains. Care should be taken in this flushing so
that the highly chlorinated water will not cause damage to adjacent
property or cause fish kill in adjacent streams.
E. After final flushing and before the water main is
replaced in service, a sample or samples shall be collected from the
end of the line, shall be tested for bacteriological quality in accordance
with Standard Methods, and shall show the absence of coliform organisms.
At least one sample shall be collected from the new main and one from
each branch. If the initial disinfection fails to produce satisfactory
bacteriological samples, the main may be reflushed and shall be resampled.
If check samples show the presence of coliform organisms, then the
main shall be rechlorinated until satisfactory results are obtained.
F. Depositing hypochlorite powder or tablets in the main
as it is being laid will not be an acceptable substitute for the above-mentioned
sterilization procedure.
The installation, testing and sterilizing of
all water mains to be connected to the Town of Seneca Falls water
systems must be witnessed and approved by the Superintendent or a
person designated by him or her to witness such tests.