33 05 05.31 - Hydrostatic Testing.pdf

33 05 05.31 – HYDROSTATIC TESTING

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 1 009280.0426

SECTION 33 05 05.31 – HYDROSTATIC TESTING

PART 1 - GENERAL

1.1 SUMMARY

A. Section Includes: Hydrostatic testing of pressure piping.

1.2 REFERENCE STANDARD

A. American Water Works Association:

1. AWWA C600, Installation of Ductile Iron Water Mains and Their Appurtenances.

1.3 SUBMITTALS

A. Section 01 33 00 – Submittal Procedures: Requirements for submittals.

B. Submit following items a minimum of 72 hours prior to start of testing:

1. Testing procedures.

2. List of test equipment.

3. Testing sequence schedule.

4. Provisions for disposal of flushing and test water.

5. Certification of test gage calibration.

C. Test and Evaluation Reports: Indicate results of piping tests.

1.4 QUALITY ASSURANCE

A. Design Criteria for Testing Water Mains:

1. Required Test Pressures: The water mains shall be tested as specified in this

Section.

2. Pressure shall not vary more than plus or minus 5 psi from the required test procedures.

3. Required test pressures shall be obtained upon request from Engineer.

PART 2 - PRODUCTS

2.1 HYDROSTATIC TESTING

A. Equipment:

1. Pressure pump.

2. Pressure hose.

3. Water meter.

4. Test connections.

5. Pressure relief valve.

6. Pressure Gage: Calibrated to 0.1 psi.

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 2 009280.0426

PART 3 - EXECUTION

3.1 PREPARATION

A. GENERAL REQUIREMENTS

1. Conduct tests specified herein so that each pipe line installed in the Project is tested to the Engineer's satisfaction. All piping shall be properly flushed and tested unless otherwise approved by the Engineer.

2. The Contractor shall furnish and install all means and apparatus necessary for getting the air or water into the pipeline for flushing and testing including pumps, pipe connection to main, compressors, gauges, and meters, any necessary plugs and caps, and any required blow-off piping and fittings, etc., complete with any necessary reaction blocking to prevent pipe movement during the flushing and testing. The Contractor shall provide water for all flushing and testing of pipelines.

Only potable water shall be used for flushing and testing the potable water system.

3. Contractor shall thoroughly clean all new pipe by flushing with water or other means to remove all dirt, stones, pieces of wood, etc., which may have entered the pipe during the construction period. If after this cleaning any obstructions remain, they shall be corrected by the Contractor, at his own expense, to the satisfaction of the Engineer. Pipelines shall be flushed at the rate of at least 3.0 feet per second for a duration suitable to the Engineer or shall be flushed by other methods approved by the Engineer.

4. All work involving chlorinated water discharges to the surface, such as but not limited to: flushing of water mains and hydrants, water system disinfection, and hydrostatic testing shall be dechlorinated in accordance with PADEP regulations pertaining to the Planned and Unplanned Discharges of Chlorinated Waters to Surface Waters and in accordance with AWWA C655 – Field Dechlorination.

3.2 FIELD QUALITY CONTROL

A. INSPECTION

1. Inspect each section of pipe, joint alignment, and each pipe fitting prior to backfilling to assure the maximum deflection present in each joint does not exceed the manufacturer's recommendations.

2. Any and all defects shall be corrected by Contractor at no additional cost to Owner and to the satisfaction of Engineer prior to backfilling. This shall be completed before the work shall proceed and before acceptance of and/or payment shall be made. Remove rejected pipe and/or fittings from project.

3. Pipelines shall be inspected to assure the lines are installed at a constant or increasing grade so as to eliminate the possibility for air accumulation at an intermediate high point.

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 3 009280.0426

4. The Engineer reserves the unqualified right to oversee and inspect the testing procedures; determine the acceptability of all tests performed; and to totally control the progress or continuation of pipe laying operations in view of testing not in compliance with the herein stated criteria. The decision of the Engineer in regard to all matters related to testing shall be considered as final.

B. HYDROSTATIC TESTING

1. General:

a. Provide test pump, pipe connection to main and all necessary tools, materials and equipment, including the test gauge, required for the main testing.

b. Conduct pressure and leakage tests specified herein so that each water main installed in the Project is tested to the Engineer’s satisfaction.

c. The hydrostatic test shall be in accordance with the following requirements:

1) Ductile Iron Pipe Water Mains: AWWA C600.

d. The hydrostatic testing equipment and installation shall be satisfactory to the Engineer prior to testing.

e. Conduct the hydrostatic pressure and leakage tests in the presence of and to the satisfaction of the Engineer.

f. When the length of a water main exceeds 1,200 feet, the Engineer reserves the right to require that the water main be tested in sections, the length of each section to be determined by the Engineer.

g. Water for testing shall be furnished by the Contractor. The Contractor may utilize the existing water system for the quantities required;

however, the Contractor must coordinate all arrangements and conform to the Owner’s standards for use and connection. The Owner will waive charges for water utilization, so long as the use of water is properly coordinated with the Owner to the Owner’s satisfaction.

h. The Contractor will be required to perform hydrostatic pressure testing concurrent with installation of the pipe system.

i. No testing will be authorized unless ambient air temperature is 35oF or higher.

j. Any leaks or defective pipe disclosed by the hydrostatic test shall be repaired or replaced by the Contractor, at his own expense, and the test repeated until all such piping passes the specified test.

k. New water service connections installed shall be installed and connected to the water distribution main and tested concurrently with the entire water distribution system. The extent of water service connection testing shall be to the curb stop. Upon completion of satisfactory testing and disinfection, the water service connection shall be connected to the existing service line in accordance with the details shown on the Drawings.

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 4 009280.0426

2. Preparation:

a. The Contractor may, at his option, completely backfill the trench or partially backfill the trench over the center section of each pipe length prior to carrying out the pressure test. The Engineer reserves the right, however, to direct that the entire trench be backfilled, if traffic or other local conditions require such action.

b. The section of water main being tested must be filled with water for the following minimum time periods before the main is tested:

1) Ductile Iron Pipe Water Mains: 24 hours.

c. The test shall be made by closing valves, when available, or by placing temporary bulkheads in the pipe and filling the line slowly with water.

The Contractor shall be responsible for ascertaining that all test bulkheads are suitably restrained to resist the thrust of the test pressure without damage to, or movement of, the adjacent pipe. Care shall be taken to see that all air vents are open during filling.

d. Where any section of a main is provided with concrete reaction backing, the hydrostatic pressure test shall not be made until at least five (5) days have elapsed after the concrete reaction backing was installed. If high early strength cement is used in the concrete reaction backing, the hydrostatic pressure test shall not be made until at least two days have elapsed.

e. The pipelines shall be filled at a rate that will not cause any surges or exceed the rate at which the air can be released through the air valves at a reasonable velocity; all the air within the pipelines shall be properly purged. After the pipeline or section thereof has been filled, it shall be allowed to stand under a slight pressure for a sufficient length of time to allow the escape of air from any air pockets. During this period, bulkheads, valves, and connections shall be examined for leaks. If leaks are found, corrective measures satisfactory to the Engineer shall be taken.

3. Pressure Test:

a. After the pipeline has been filled with water for the minimum time periods required, conduct a pressure test. Test pressure and duration for each section of water main to be tested shall be as follows:

1) Ductile Iron Pipe Water Mains: 150 psi for at least four (4) hours.

b. Apply the specified test pressure by means of a pump connected to the pipe in a manner satisfactory to the Engineer. Before applying the specified test pressure, all air shall be expelled from the pipe. If hydrants or blow offs are not available at high places, Contractor shall make the necessary taps at points of highest elevation before the test is made and insert the plugs after the test has been completed, at no additional cost to Owner. Extreme care must be exercised to ensure that all air is expelled from the pipeline during the filling of the pipe with water.

c. Carefully examine all exposed pipes, joints, fittings, and valves during the test, and tighten all joints showing visible leakage. Remove all defective pipe, fittings, and valves from the line and replace by the Contractor at his expense.

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 5 009280.0426

d. The section under test shall be brought back to test pressure at one-half hour intervals during the testing should repressurization be needed.

Engineer will record both the makeup water amount and pressure at each one-half hour repressurization.

4. Leakage Test:

a. Conduct concurrently with the pressure test.

b. Provide suitable means to measure the leakage during the pressure test, and a record of water added to the pipeline shall be kept for a period of time to match the pressure test.

c. Leakage is defined as the quantity of water that must be supplied into the newly laid pipe, or any valve section thereof, to maintain pressure within 5 psi of the specified test pressure after the air in the pipeline has been expelled and the pipe filled with water.

d. All piping inside chambers, valve pits, etc. shall show no leakage.

e. Leakage in Ductile Iron pipelines shall be acceptable when it is less than the amount calculated by the following formula:

𝐿 =

𝑆𝐷√𝑃

148,000

L = Allowable Leakage (gph) S = Length of Pipeline Tested (ft.)

D = Nominal Diameter of Pipe (in.)

P = Average test pressure during test period (psig)

Allowable Leakage (GPH) per 1,000 feet of Ductile Iron Pipe is defined by the following table:

Avg. Test Pressure

(psi)

4” Nom.

Pipe

Diameter

6” Nom.

Pipe

Diameter

8” Nom.

Pipe

Diameter

10” Nom.

Pipe

Diameter

12” Nom.

Pipe

Diameter 300 0.47 0.70 0.94 1.17 1.40 275 0.45 0.67 0.90 1.12 1.34 250 0.43 0.64 0.85 1.07 1.28 225 0.41 0.61 0.81 1.01 1.22 200 0.38 0.57 0.76 0.96 1.15 175 0.36 0.54 0.72 0.89 1.07 150 0.33 0.50 0.66 0.83 0.99 125 0.30 0.45 0.60 0.76 0.91

f. Should any test of a section of pipeline disclose leakage greater than that permitted, locate and repair the defective joints and/or pipe at the Contractor’s expense. All visible leaks are to be repaired regardless of the amount of leakage.

C. FIRE HYDRANT TESTING REQUIREMENTS

1. After installation and after pressure testing the water main, test the hydrant as follows:

a. Pressure Test

1) Open the hydrant fully and fill with water; close all outlets.

Herbert, Rowland & Grubic, Inc. 33 05 05.31 - 6 009280.0426

2) To prevent caps from being blown off dry-barrel hydrants and to prevent other possible damage, vent air from the hydrant by leaving one of the caps slightly loose as the hydrant is being filled.

After all air has escaped, tighten the cap before proceeding.

3) Apply line pressure.

4) Check for leakage at flanges, nozzles and operating stems.

5) If leakage is noted, repair or replace components or complete hydrant until no leaks are evident.

b. Drainage Test for Dry-Barrel Hydrants

1) Follow the pressure test, close hydrant.

2) Remove one nozzle cap and place pylon or hand over nozzle opening.

3) Drainage rate should be sufficiently rapid to create a noticeable suction.

4) After backfilling, operate the hydrant to flush out any foreign material.

5) Tighten nozzle caps, then back them off slightly so that they will not be excessively tight; leave tight enough to prevent removal by hand.

6) If hydrant has a plugged drain connection, Contractor is required to pump the barrel dry after each use.

3.3 ACCEPTANCE

A. Acceptance: Observation of successful testing of piping by the Engineer does not constitute acceptance of the system or any portion thereof. Upon completion of any determined portion of a total system, and successful testing thereof, the Engineer may recommend final acceptance to the Owner. Only upon final inspection by the Owner and Engineer and upon written acceptance for same will the system or portion thereof be considered substantially completed. Upon such acceptance, the warranty period will commence. If, during the final inspection, any irregularities are observed, the condition must be corrected at the Contractor's expense prior to acceptance.

END OF SECTION 33 05 05.31