procedures for wet-tapping water mains - DC Water

PROCEDURES FOR WET-TAPPING WATER MAINSAll requests for wet-tap connections to DCWASA water mains shall be referred to theSupervisor, Water and Sewer Design Section for review and approval.The following procedures and guidelines have been developed to assist in determining: 1)if a connection can be made using wet-tapping process; and 2) the criteria and proceduresto be followed in connection with wet-tapping of water mains.1. Identification of Mains Suitable for Wet-tappingThe following criteria must be met before consideration can be given to allowing a newconnection to be made in an existing main by wet-tapping operations.• Wet-taps shall only be allowed in water mains that have not exhibited excessivemain breaks and meet the requirements of the pipe condition assessment furtherdescribed in Section 3.• The Supervisor, Water and Sewer Design Section, or his designated person, shallreview the main break database to determine break history in the main beingconsidered for wet-tapping. If the main break database shows that the main doesnot have a history of excessive breaks, the Supervisor, Water and Sewer DesignSection, or his designated person shall forward the wet-tap request to the WaterDistribution Division Manager, DWS, or his designated person who shall reviewthe wet-tap location for recent main break information that may not be containedin the database. The DWS shall respond to the DETS within 7 calendar days ifthe location for the proposed wet-tap is acceptable with respect to main breakhistory.• Mains must be 8-inch diameter and larger.• Wet-taps shall not be allowed in mains larger than 16-inch diameter, unlessspecifically approved by the Supervisor, Water and Sewer Design Section, or hisdesignated person, and the Water Distribution Division Manager, or hisdesignated person.• If the above criteria is met and a wet-tap connection is found to be acceptable, theapplication shall be required to post a cash deposit in the amount of $1,000 whichwill be used to pay for the cost of the pipe condition assessment described furtherin Section 3. The applicant will be charged for the actual costs of the testing andinspection, and any remaining amounts will be returned to the applicant.Revised 1/25/2006 1

2. Wet-tapping CriteriaWet-taps shall be made in accordance with the following criteria:• The tapped connection shall be at least one size smaller than the pipe beingtapped, i.e. 12-inch diameter pipe being tapped, the maximum tapping diameterwould be 10-inch diameter.• Wet-taps shall be at least 6-inch diameter and larger, no 4-inch diameter taps ortapping valves are permitted. Two (2”) inch taps will be allowed with a preapprovedtapping assembly.• Tapping sleeves shall be installed at least 4-feet from any exposed pipe joint orexisting tap.• Tapping sleeves shall be full-body ductile iron. Valves shall be as approved byDCWASA. Contractor shall submit shop drawings of the proposed sleeve andvalve to the Supervisor, Civil and Structural Section for approval prior toundertaking any work.• Wet-taps shall be made only by experienced contractors specializing in theinstallation of wet-taps. (Refer to Contractor experience and qualifications,Section 5 for requirements relative to this item.)• Wet-tap installation and testing shall be made in accordance with themanufacturer’s recommendations. The tapping saddle shall be designed for thetest pressure of the main being tapped.• Prior to undertaking any work, or ordering of materials, the Contractor shall testpit the pipe at the location of the tap and verify the outside diameter of the pipe toinsure that the correct size saddle is provided.• Contractor shall be responsible for obtaining a Public Space Permit from DDOTand complying with all requirements of this permit, including placement andmaintenance of temporary steel plating.• Contractor shall provide all required sheeting, shoring, bracing, dewatering, etc.to maintain a safe and dry excavation throughout the wet-tap installation process.3. Pipe Condition AssessmentRevised 1/25/2006 2

• In order to determine if the pipe is suitable for tapping, the DCWASA Inspectorwill arrange to have the pipe tested by DCWASA’s Corrosion Consultant.• The pipe condition assessment shall be undertaken at the same time as theContractor is undertaking the test pit operations to confirm the outside diameter ofthe pipe. To avoid delays, the Contractor shall provide DCWASA with at least 7calendar days advance notice when the test pitting operations will be undertakenso that the DCWASA Inspector can coordinate the pipe condition assessmenttesting.• The Contractor shall allow DCWASA’s Corrosion Consultant 4 hours to inspectand test the pipe. The Contractor shall completely expose and cleanapproximately 4 feet of pipe so that DCWASA’s Corrosion Consultant can obtainfull access to the pipe to conduct the inspection and testing of the pipe.• Following completion of the testing, the Corrosion Consultant will advise theDCWASA Inspector of the suitability of the pipe to receive the wet-tap. If thepipe is deemed in suitable condition for wet-tapping, the Contractor will beauthorized to proceed with the wet-tapping operation. The Contractor shallcoordinate the time and date of the work with the DCWASA Inspector.• If the main is found to be unsuitable for wet-tapping, the Contractor will beadvised that the connection to the main shall be made by dry cut operations andnot by wet-tapping. Under these conditions the Contractor shall coordinate theshutdown of the main with the DCWASA Inspector. This shutdown may requirerescheduling the work depending on the availability of DWS crews to shutdownthe main.4. WASA Inspection• No work associated with the wet-tapping of water mains shall be undertakenwithout a DCWASA Inspector present. The Contractor shall provide theDCWASA Inspector at least three (3) days notice to schedule when wet-tappingoperations are to take place.• Following completion of the wet-tap, the Contractor shall provide the pipe couponto the DCWASA Inspector. The pipe coupon will be tagged by the inspector anddelivered to DCWASA’s Corrosion Consultant for further testing and evaluation.5. Contractor Experience and Qualifications• Wet-tapping of water mains shall only be made by individuals experienced andqualified in wet-tapping operations and procedures.Revised 1/25/2006 3

• Any Contractor interested in performing wet-tapping operations on DCWASAwater mains shall be approved prior to undertaking any wet-tapping operations.The Contractor shall submit his experience and qualifications to the Supervisor,Water and Sewer Design Section for review and approval. As a minimum, theindividuals performing the work shall have at least five (5) years experience in thewet-tapping of water mains in the sizes being considered. Contractor shallsubmitted proof of experience and qualifications including, but not limited to,listing of similar projects completed over the past three (3) years including clientreference; listing of equipment; and resumes of personnel to be used on theproject. Contractors who are approved for wet-tapping operations by anotherlocal jurisdiction may submit the appropriate approval certification for approval.The Contractor shall perform the tap-work under the supervision of a certifiedDistrict of Columbia Master Plumber. The work shall be inspected for approvalby the District of Columbia after DCWASA approves the work.• In addition to the submission of experience and qualifications of the field crews,the Contractor shall submit his proposed sequence of operations for tapping themains, discussing in place quality control and test procedures to be used to insurethat the wet-tap is successfully made.6. Maintenance Bond• The Contractor shall guarantee that the wet-tap connection shall be leak-free for aperiod of two (2) years.• The Contractor shall post with DCWASA, an annual Maintenance Bond in theamount of $15,000. The bond shall require that the Contractor address anyrepairs associated with leaking sleeves or valves that are found to be the result ofpoor workmanship or materials. If any portion of the Bond is used to addressrepair or replacement issues, the Contractor shall restore the full amount of theBond before being permitted to undertake additional wet-taps in the system.Revised 1/25/2006 4