Ord. 0058A 1968-10-24 DINANCE NO. ~SA ~\ ~ ~ ~'
AN ORDINANCE AMENDING ORDINANCE NO. ~8
ENTITLED "PEARLAND SUBDIVISION REGULATION"
BY ~DDING PROVISIONS FOR LEAKAGE TESTS
FOR SEWER LINES AND TESTS FOR WATER LINES;
ESTABLISHING THE E~'~CTIVE DATE; PROVIDING
FOR SEPARABILITY CLAUSE; AND DECLARING AN
EMERGENCY:
BE IT 0RDAII~ED BY THE CITY COUNCIL OF THE CITY OF PEARLAND,
TEXAS:
Section I. Ordinance Number ~8, Section V-7 (Sanitary
Sewer) is amended by adding the following as Section V-TC:
C. Ail sanitary sewer lines proposed to be tied into the
City's sanitary sewer system now or in the future shall be tested
in compliance with the following and approved by the City before
any access to City lines shall be permitted and is a prerequisite
for City acceptance and continuous maintenance. LEAKAGE TESTS FOR SEWER LINES
(1) Infiltration Test
This test may be used where the ground water level
rises to a plane that will provide a test head not less than that
specified for exfiltration tests, Ail pumps will be stopped and
the ground water allowed to return to its normal level and remain
so for at least 24 hours before the test is started. The pipe
wiI1 be filled with water to the overflow depth of the measuring
device and leakage will be capable of flowing at a uniform rate
through such device placed at the downstream end of the sewer
being tested. Leakage will be determined by measuring the flow
through the measuring device during a given time. Five measure-
ments will be made and the average measurements will be used,
discaring any one, except the last, that varies by more than
~0~ from the average of the other four. If the results of the
test are otherwise satisfactory, but the last of the five measure-
ments show leakage in excess of the allowable, the test shall be
continued to determine if additional leaks may have developed
during testing.
(2) Exfiltration Test
The Contractor shall notify the City when backfill
has been completed. If he wishes to keep the pipe full of water
for 24 hours to allow for absorption by the pipe, he will be
given ~8 hours notice before the test to allow time for filling
and soaking the pipe. At least two hours before the start of
the test, the water shall be bled off to below the level of the
top of the pipe at its lower end and allowed to remain so until
the water level remains static at this level or continues to
fall. The test will be made in the following manner.
A water-tight plug, equipped with a pipe riser,
will be inserted and braced in the inlet opening in the downstream
manhole and a similar plug, equipped with a suitable vent pipe
that will permit the escape of air in the pipe at its upper end,
will be inserted and braced in the outlet opening in the upstream
manhole.
The sewer and risers will be filled with water
up to a level that is ten (10) feet above the flow line of the
sewer at the lower end plus the vertical distance from the invert
of the sewer at its lower end to the static level of any ground
water that may exist.
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The sewer will be filled with water in a
continuous operation as rapidly as the supply will permit and
the test measurement will begin as soon as the water is at the
required level. The drop in water level will be measured each
minute for five minutes or until the level has dropped twelve
inches, whichever occurs first. The water will then be brought
back immediately to the required level and the test repeated
until five such observations have been made. The average of
these results will be used, discarding any one of the five ob-
servations, except the last, that varies more than ~0~ from the
average of the other four. If the tests are otherwise satisfactory,
but the last of the five observations shows leakage in excess of
that allowed by the specifications, the tests will continue to
be run to determine if additional leaks have developed during
testing.
The total leakage in cubic inches shall be the
total cross-sectional area in square inches of the inside of
the two risers and of any stacks in the sewer multiplied by the
drop in water level in inches. Table I gives the volume per
inch of depth, in cubic feet and gallons, for several sizes of
risers or stacks and the allowable leakage in gallons per minute
per 100 foot of pipe for 6 inch to 36 inch pipe for concrete,
clay and asbestos-cement pipe.
(3) Defective Sewers
Sections of sewers that show leakage in excess of
that which is allowable by these specifications shall be taken
up and relaid or otherwise made good by repairs of a permanent
nature with methods and materials approved by the City. Visible
leaks shall be repaired as soon as found. Any individual leaks
that may appear shall be repaired whether or not the overall
section meets the leakage requirements. For this purpose any
steady stream will be considered a leak while a drip will not.
Individual leaks will ordinarily be revealed by looking through
the sewer with a light while the ground water level is over the
sewer, during water tamping operations or immediately after
water from exfiltration tests is emptied from the sewer.
Settlement of backfill during exfiltration tests will be taken
as an indication of leakage in the sewer. Sewer which fail to
meet:the requirements of the leak test will, after repairs by
the Contractor have been made, again be tested for leakage.
(4) Costs of Leak Tests
The Contractor shall supply all water for the
tests, plugs, risers, measuring devices, labor and equipment
necessary to convey water into the sewer and other incidental
work in conducting the test and the cost thereof shall be inc-
luded in the price for constructing the sewer.
TABLE I
Measuring Leakage in Sewers
Diameter of Volume Per Inch of Depth
Riser or Stack Cu. In. Gallons
1" 0.7854 .o034
2" 3.1416 .0136
2~" 4.9087 .0213
3" 7.0686 .0307
12. 664
" 19.63~0 .08~2
6" 28.2748 .1227
8" .2182
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(Allowable Leakage (Gal. Per Minute Per 100 Ft.)
Size of Pipe Concrete PipeI Vitrified Clay Pipe2 Asb. Cem. Pipe3
6" .0789 .0395 .0079
8" .1052 .o526 .0105
10" .1315 .o658 .0132
12" .1578 .0790 .0158
14" .0184
15" .1973 .0987 -
16" .0210
18" .2367 .1184 .0237
20" .0263
21" .2762 .1381 -
24" .3157 .1579 .0316
27" .3551 .1776 .0355
30" .3946 .1973 .0395
36" .4735 .2368 .0474
1. Equivalent to 1000 gal. per inch diameter per mile per day.
2. Equivalent to 500 gal. per inch diameter per mile per day.
3. Equivalent to 100 gal. per inch diameter per mile per day.
Section II. 0rdidnance Number 58, Section V-8 (Water Lines)
is amended by changing the existing paragraph to 8a and adding
the following as Sections 8b and 8c.
b. Two (2) inch P. V. C. Ring-Tite pipe and
fittings shall be permitted and shall conform to the require-
ments of ASTM Resin Specifications D-1784-60T or better. Ail
pipe shall be hydrostatically tested for 1,000 hours at 400 p.s.i.
in accordance with ASTM 1598-60T.
c. Ail water lines proposed to be tied into the
City's water distribution system now or in the future shall be
tested in compliance with the following and approved by the City
before the City will accept and provide continuous maintenance
of them.
TESTS FOR WATER LINES
(1) Time for Making for Tests: Tests shall be made
only after completion of partial backfill and not until at least
36 hours after the last concrete thrust or reaction backing has
been cast with early strength cement, or at least 7 days after
the last concrete thrust or reaction backing has been cast with
standard cement. Pipe lines shall be tested before backfilling
at joints, except when local conditions, in the opinion or the
City are such that the trenches must be backfilled immediately
after laying the pipe, in which case the pressure tests may be
made after backfilling has been completed but before replacement
of permanent paving.
(a) Leakage tests of asbestos-cement pipe
shall be made only after the pipe has been filled with water for a
minimum of 24 hours.
(b) Where practicable, pipe lines shall be
tested in lengths between line-valves or plugs of not more than
1500 feet.
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(2) Procedure for Testing. Each section of pipe line shall
be chlorinated just prior to testing, Each section of pipe line
shall be slowly filled with water and the specified test pressure,
measured at the point of lowest elevation, shall be applied by
means of a test pump connected to the pipe, in a manner satis-
factory to the City. The test pump, pipe connections and all
necessary apparatus, gages and meters shall be furnished, in-
stalled and operated by the Contractor, at his expense.
Expelling Air Before Tests. During the filling of the
pipe and before applying the specified test pressure, all air
shall be expelled from the pipe line. To accomplish this, taps
shall be made, if necessary, at point of height elevation, and
after completion of the test the taps shall be tightly plugged
unless otherwise specified. Taps and plugs will be installed by
the Contractor.
(3) Pressure Tests.
(a)Hydrostatic Test Pressure
(i) Cast Iron Pipe - 12~ psi
(ii) Asbestos Cement Pipe: The pipe shall be
subjected to hydrostatic pressure 50 percent above normal operating
pressure but not exceeding 50 lbs. more than the rated working
pressure of the pipe. The normal operating pressure shall be
defined by the City.
(b) Duration of each pressure test shall be not less
than one hour unless otherwise directed by the City.
(c) Examination under Pressure. Ail exposed pipes,
fittings, valves, hydrants, joints and asbestos-cement couplings
will be carefully examined. If found to be cracked or defective,
they shall bs removed and replaced by the Contractor with sound
material at the Contractor's expense. The test shall then be
repeated until satisfactory to the City.
(4) Leakage Tests.
(a) Hydrostatic Test Pressure
(i) Cast Iron Pipe 125 psi.
(ii) Asbestos-Cement Pipe - The pressure to be
maintained during the test shall be the normal operating pressure
and shall be specified by the City.
(b) Duration of each leakage test shall be not less
than 2 hours where joints are exposed, and not less than 24 hours
where the joints are covered.
(c) Examination of Individual Joints for Leakage:
Ail exposed pipes, fittings, valves, hydrants and joints shall be
examined for leakage during the test. Any joint found where the
accumulated leakage of that joint exceeds the rate of leakage
specified in Table A shall be rejected by the City. Ail visible
leaks at exposed joints, and all leaks evident on the surface
where the joints are covered, shall be stopped and leakage minimized,
regardless of total leakage as shown by test.
(d) Overall Permissible Leakage:
(i) Cast Iron Pipe: Pipe lines shall show
leakage not exceeding 100 gallson per 24 hours per inch diameter
per mile of pipe.
(ii) Asbestos-Cement Pipe: No pipe installation
will be accepted until or unless the leakage for the section of
line tested is less than the rate of leakage specified in Table A.
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t^
In calculating leakage the City will make allowance for added
joints in pipe line above those incidential to normal 13 foot
lengths of pipe and for which Table A applies. Should any test
of a section of pipe line disclose joint leakage greater than
that permitted, the Contractor shall at his own expense locate
and repair the defective joints until the leakage is within the
permitted allowance.
TABTE .A.
T,FAKAGE ALLOWANCE
Gallons Per 100 Couplings Per Hour
Pipe Test Pressure
Dia. (psi)
(inches) 50 75 100 125 150 200 225
3 1.15 1.40 1.63 1.81 1.99 2.30 2.14E
4 1.54 1.87 2.16 2.42 2.65 3.07 3.25
6 2.30 2.80 3.25 3.63 3.98 4.60 4.88
8 3.07 3.73 4.33 4.83 5.30 6.13 6.,50
10 3.83 4.66 5.41 6.06 6.63 7.66 8.12
12 4.60 5.59 6.50 7.25 7.95 9.20 9.75
14 5.37 6.52 7.58 8.46 9.28 10.73 11.38
16 6.13 7.45 8.66 9.66 10.60 12.27 13.00
18 6.90 8.38 9.75 10.87 11.93 13.80 14.62
20 7.66 9.31 10.83 12.08 13.26 15.33 16.25
24 9.20 11.17 13.00 14.50 15.90 18.40 19.50
30 11.50 13.98 16.25 18.13 19.88 23.00 24.37
36 13.80 16.80 19.50 21.75 23.85 27.60 29.24
Evaluated on basis of 150 psi. this leakage is approximately
equal to 65 U. S. gallons per 24 hours per mile of pipe, per
inch of pipe diameter for pipe in 13-foot lengths.
Section III. This ordinance shall become effective im-
mediately upon its passage and lines not accepted by the City
shall be required to pass these tests before acceptance by the
City.
Section IV. If any portion, paragraph or part of this
ordinance shall be held to be illegal or unconstitutional then
such holding shall in no wise affect the remainder of such
ordinance and the same shall remain in full force and effect
as if such portion so held to be unconstitutional had never been
questioned.
Section V. The further fact that the City of Pearland now
has no adequate provision in Subdivision Ordinance No. 58 regulating
the testing of sewer and water lines, and the need for such
regulations constitutes an imperative public necessity, this
ordinance shall take effect immediately from and after its passage
and approval and it is so ordered.
PASSED, APPROVED AND ADOPMD this the ? 4 day of
, A. D. 1968.
C
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Attest: CITYY OF PEARLAND
�� at/ By: \�
ity Secret y
Mayor