The Contractor shall perform a Leak Detection Survey of the Lowell Regional Water Utility’s (“the City”) potable water distribution system (215 miles of water main) and present relevant findings to the City as requested by the Executive Director and as directed by the Superintendent of Distribution and staff. The Contractor's Scope of Services shall be to conduct a Leak Detection Survey (as detailed in Part B: Leak Detection Survey Duties) as authorized by the City. All contractors submitting bids for the Leak Detection Survey must have a minimum of five (5) years' experience and provide the City with supporting documentation. PART A: LEAK DETECTION SURVEY RESPONSIBILITIES Leak Detection Survey: The Contractor shall provide sufficient appropriately certified leak detection staff, all required leak detection equipment, and sufficient appropriate vehicle(s) to fully perform and complete the leak detection survey. Financial implications regarding the Leak Detection Survey, including, but not limited to, project administration, project management, coordination with the City, performance of the entire Leak Detection Survey, report preparation, and all related expenses shall be included in the comprehensive per mile rate for leak detection of water main (cost proposal) for the Leak Detection Survey. There shall be no separate reimbursement for any additional project costs. PART B: LEAK DETECTION SURVEY DUTIES 1. The Contractor shall administer, manage, and coordinate all necessary work to complete the Scope of Services for each specific Leak Detection Survey. The Contractor shall discuss with City officials the Scope of Services, miles of Leak Detection Survey required by the City, project schedule, assignment of a Contractor designee (to serve as the primary point of contact), and water system mapping. The Contractor shall report any significant issues to the Superintendent of Distribution prior to commencing the Leak Detection Survey. The Leak Detection Survey shall be executed between the City and the Contractor. 2. The following general procedures shall be followed to perform the Leak Detection Survey: a. Use sound intensifying equipment capable of detecting small amounts of leakage; b. Directly place correlating accelerometers on every hydrant, selected main line valves, or selected sidewalk service connections to determine whether there is an unknown correlated leak between the points of contact. The maximum distance between the initial listening points shall not exceed 700 feet. The Contractor shall then select, if needed, additional mainline valves, hydrant valves, service connections, or hydrant ports to accurately pinpoint the location of every leak found; c. Every correlation performed (not just those that indicate a potential leak) must be saved and submitted to the City in order for the City to review the data at a later time. The Contractor shall supply the City with a licensed copy of the software, the cost of which shall be included in the per mile cost, that will allow the City to review the survey data files; d. All leak site pinpointing shall be performed with a correlation system utilizing two (2) or more sensors and verified with a sonic ground sounding technique; e. The leak shall be classified by estimated water loss and severity. A leakage site report shall be prepared for each suspected point of leakage, and it shall include a copy of each leak correlation graph that indicates a potential leak. 3. The Contractor shall provide sufficient appropriately certified leak detection staff, all required leak detection equipment, and an appropriate vehicle to fully perform and complete the Leak Detection Survey. The City will provide a guide to assist the Contractor and two (2) copies of the water system map if requested. 4. Upon survey completion, a Leak Detection Survey Report (“the Report”) shall be prepared and include: a copy of the individual leak reports, a total estimated water loss, the start and completion dates of the Leak Detection Survey, the number of leaks by classification per Leak Detection Regulations 360 CMR 12.00, Section 12.09 (2), list of leakage sources (mains, services, valves, hydrants) by number and estimated flow amount, a summary of the overall project, and, if found, a list of active blow-off valves with their locations and estimated flow. The Report shall also contain detailed diagrams for each identified leak indicating the date of the survey, specific location of the leak, estimated leakage amount, suspected type of leak, and a copy of each leak correlation graph. Three (3) copies of the Draft Leak Detection Report shall be submitted to the Superintendent of Distribution within one (1) month of completion of the field work. Three (3) copies of the Final Leak Detection Report shall be submitted after the Draft Report is reviewed by the Superintendent of Distribution. 5. The City will be responsible for the arrangement and payment of police details and for locating and/or excavating access points to the community water system that are deemed necessary.
