Section 7 3. Testing And Inspection
SECTION 7 SANITARY SEWER GRAVITY COLLECTION SYSTEM
3. TESTING AND INSPECTION
A. The Contractor and Engineer shall inspect all installed sewer lines by visually checking each section for alignment prior to placing into service. A full circle of light shall be seen by looking through the pipe at a light held at the opposite end of the section of sewer line being inspected. The Contractor shall make any corrections required in line or grade.
B. The City’s Inspector must be notified in writing at least 24-hours prior to all scheduled formal tests.
C. Leakage Tests:
1. Prior to testing for leakage, the trench shall be completely backfilled and compacted properly. Test shall be performed just prior to final paving over trench.
2. Test lines for leakage by exfiltration tests. In areas where pipe is laid below groundwater level, assure that there is no infiltration prior to performing the exfiltration tests.
3. Visible leaks into the system shall be corrected regardless of the amount of leakage.
4. The infiltration test procedure shall be used when the water table is 2 feet or more above the top of the pipe at the upper end of the pipe line section to be tested. Infiltration shall be measured using a suitable weir or other acceptable device.
5. An exfiltration test shall be performed, when an infiltration test cannot be properly performed.
6. The exfiltration test procedure shall be performed by filling the manhole, line and laterals with clean water. The filled lines shall be allowed to stand until the pipe has reached its maximum absorption, but not less than 4 hours. After absorption, the head shall be re-established. The allowable limits of infiltration or exfiltration for the entire system, or any portion thereof, shall not exceed a rate of 100 gallons per inch of inside pipe diameter per mile of pipe per 24 hours; no additional allowance will be made for service laterals. When leakage exceeds the maximum amount specified, satisfactory correction shall be made and system retested. Correction and retesting shall be made at Contractor’s expense.
7. Manhole exfiltration leakage shall not exceed 4 gallons per day per manhole tested.
8. After all testing and paving has been completed, the sanitary sewer system shall be televised, at Contractor/Developer’s expense. Digital copy of the sewer line video on acceptable form of media and inspection report shall be reviewed by the City Engineer or his designee. Contractor shall be responsible for correcting any deficiencies noted prior to the Engineer of Record’s certification of completion of the work to any agency.