SECTION 6 WATER DISTRIBUTION
C. FLUSHING TESTING AND DISINFECTION
A. Upon completion of the installation, the water main shall be thoroughly canon flushed through a riser. The water shall be properly disposed not to cause a flooding problem. All water used must be metered through a City supplied construction meter. The contractor can obtain the meter through proper application and payment of the required fee at the City’s Public Works Department.
B. The complete water system shall be pressure tested and disinfected. The pressure test shall be for two hours at 120 psi minimum test pressure in accordance with ANSI/AWWA C600-93 latest revision. No more than 5 psi drop over the length of test. Final approval will be based on leakage test results. The maximum allowable leakage shall be determined by following formula:
AWWA Formula: L = SD √ P
Where: D = Pipe Diameter in inches
S = Length of lines in lineal feet
P = Average test pressure
L = Allowable leakage for system in gallons per hour
The pressure test shall be witnessed by a representative of the City of Miami Beach, Public Works Department and the Engineer of Record or his representative.
1. Advance notice is to be provided to the City of Miami Beach Public Works Department and the Miami-Dade County Department of Health. Bacteriological sampling points shall be provided at the location shown on the plans or as directed by the Department of Health, and paid by the contractor.
2. All Pipe lines shall be disinfected after they have been pressure tested and while still full of water, as specified in AWWA standard C601 latest revision and Miami-Dade County Health Department procedures.
3. A suitable chlorinator shall be used to inject chlorine into the lines. All connections required for the introduction of chlorine into the water lines shall be made by the Contractor. Chlorine and water shall be introduced at one end and shall be allowed to flow slowly through the lines to the other end where it shall be removed and disposed of at the Contractor’s expenses. Several points of introduction and removal of chlorine solution may have to be employed to get an even distribution through the entire section being disinfected.
4. The quantity of chlorine introduced shall be such as to insure a concentration of at least 50 parts per million in the water flowing from the line.
5. The chlorine solution shall be allowed to stand in the line for at least 24 hours or longer, if required, to destroy all harmful bacteria. At the end of the required time, the concentration of chlorine in all parts of the section shall be at least 25 ppm.
6. All valves and appurtenances in the section shall be operated at least once during the above period. After the required period, the treated water shall be thoroughly flushed from the section and the system filled with potable water.
7. The Contractor shall be responsible for coordination with Miami-Dade County Department of Health, who shall collect and test samples from main. The Contractor shall provide assistance to the Dept. of Health for the collection of samples. The samples shall be taken from each main or section of main to be placed in service where designated by the Dept. of Health. The samples must be approved by the Department of Health before the main is placed in service.
8. The Contractor shall be responsible for any rechlorination, retesting and fees that may be required until the Department of Health’s approval is obtained. The Contractor shall be responsible for the disposal of all water flushed from the system and shall safeguard all adjoining properties from damage from flooding. The Contractor shall exercise due care in the protection of private property from water damage due to his operations. In addition, the Contractor shall assume complete liability for any damage which was directly or in-directly caused by his operations.
9. All of the connections shall be disinfected by the contractor.
10. The inside of each pipe and fitting laid by the Contractor in connecting to existing mains which are isolated from the main by valves shall be swabbed with calcium hypochlorite, HTH, Perchloron, or approved equal, mixed in solution with water. The quantity of hypochlorite shall in all cases be subject to the approval of the City of Miami Beach Public Works Department, Operations Division, whose representative shall be present at all times while this phase of the work is in progress.
11. Wherever practicable, water from the existing mains flowing through the disinfected connections shall be used in disinfecting the main line in order that the hypochlorite may be removed to the greatest extent possible. In other cases, the water from the disinfected connections shall be removed by allowing it to flow into the main line as it is being drained.
12. No pipe shall be placed in service until it has been approved by the Engineering Division of City of Miami Beach and certified by the Department of Health including certified as-built drawings accepted by the City.