Flushing, hydrostatic and leakage testing shall
conform to appropriate AWWA Standard C600 for ductile-iron pipe, and
the following.
A.
Testing to be performed only after partial or complete
backfill and restraint blocking using high-early-strength cement has
had 36 hours to cure or blocking using standard cement has had seven
days to cure.
B.
The contractor shall furnish and install, complete
with reaction blocking, necessary plugs and caps required for this
operation. Main line valves shall be utilized wherever possible to
segregate test sections except as directed by the Village Engineer
or his representative.
C.
The contractor is to furnish all equipment and labor
to complete testing.
D.
The main shall be partially backfilled or braced against
movement during the test. All air must be bled out of the section
to be tested. If necessary, the contractor shall install corporation
stops at the high points, for blowoffs. After all air has been expelled,
the corporation cocks shall be closed and the pressure test applied.
After examination of exposed parts of the system, the test pressure
will be increased to 1 1/2 times the normal pressure, based upon
the elevation of the lowest point in the line or section under test,
but such pressure shall not be less than 125 psi or more than 200
psi, and exposed parts again examined. The minimum duration of the
leakage test shall be two hours.
E.
Allowable system leakage shall be as specified in
the referenced standards. If leakage in the system is greater than
allowable, the contractor will locate and repair the system at his
expense and retest, continue to test and repair the system until leakage
is within allowable limits.
A.
Flushing. The contractor shall initially flush the
pipeline completely, in sections, governed by the sources of clean
water and suitable discharge points. The pipe section shall be flushed
until the water runs clear. The contractor is advised that flushing
may not create sufficient velocities to clear the pipeline of matter
that may cause an unsatisfactory bacteriological test. Note that flushing
is not a substitute for preventive measures during construction. Permission
of the Village Engineer to stop flushing or directions to continue
flushing shall involve no responsibility for the results of the bacteriological
test.
B.
Procedure for disinfecting. The water injector for
introducing the chlorine-bearing water into the pipe should be supplied
from a tap on the pressure side of the gate valve controlling the
flow into the pipeline extension.
C.
Rate of applications. Water from the existing distribution
system or other source of supply shall be controlled as to flow slowly
into the newly laid pipeline during the application of chlorine. If
the continuous-feed method permitted by C651 is utilized, the rate
of chlorine mixture flow shall be in such proportion to the rate of
water entering the pipe that the chlorine dose applied to the water
entering the newly laid pipe shall produce at least 25 parts per million
residual, with a reading of 10 parts per million after a twenty-four-hour
period. If the slug method of C651 is utilized, the rate of chlorine
mixture flow shall be in such proportion that the chlorine dose applied
to the water entering the newly laid pipe shall produce at least 100
parts per million residual. The chlorine shall be applied continuously
and for a sufficient period to develop a solid column, or slug, of
chlorinated water that will, as it moves through the main, expose
all interior surface to a concentration of approximately 100 milligrams
per liter for least three hours.
D.
Final flushing and testing. Following chlorination,
all treated water shall be thoroughly flushed from the newly laid
pipeline at its extremities until the replacement water throughout
its entire length shall, upon testing, be proved comparable in quality
to the water served the public from the existing water supply system
and as approved by the public health authority having jurisdiction.
Should the initial treatment fail to result in the conditions specified,
the entire procedure shall be repeated until satisfactory results
are obtained. The contractor is responsible to properly dispose of
the chlorinated water. The environment to which the chlorinated water
is to be discharged shall be inspected. If there is any question that
the chlorinated discharge will cause damage to the environment, then
a reducing agent shall be applied to the water to be wasted to neutralize
thoroughly the chlorine residual remaining in the water. Where necessary,
state and county agencies should be contacted to determine special
provisions for the disposal of heavily chlorinated water.
E.
Bacteriological tests. The contractor shall make all
arrangements with the Orange County Department of Health for bacteriological
tests and shall make the tests under their direction, if required.
The contractor shall furnish all equipment, disinfectants, piping,
etc., required for the tests. Samples shall be taken in the presence
of the Village Engineer and delivered to the test laboratory by the
contractor. In the event that the initial test results do not meet
Health Department standards, the contractor shall be responsible for
flushing and rechlorinating the pipelines and retesting additional
samples until satisfactory bacteriological test results have been
achieved. All costs related in achieving satisfactory results are
to be borne by the contractor. The contractor shall obtain certificates
of satisfactory bacteriological testing and furnish them to the Village
Engineer before the request is made for acceptance of the work.
[Amended 1-19-1999 by L.L. No. 2-1999]
F.
The contractor shall furnish all water for flushing,
testing and disinfection. The contractor shall furnish all means and
apparatus for getting the water into the pipelines and shall furnish,
install and remove any additional temporary blowoff piping required
to discharge water used for flushing, testing and disinfection.
A.
The contractor shall give the Village Engineer reasonable
notice as to the time when he will be prepared to test portions of
the work, so that inspection of all testing and disinfection can be
scheduled.
B.
Upon completion of work, the contractor will provide
the Village Engineer with three sets of as-built plans of waterlines
indicating valves, fittings and hydrants, with measurements. Upon
receipt of this plan, an inspection of the work area will be made
and any deficiencies corrected by the contractor, prior to the Village
of Montgomery's acceptance of the new line.
