Introduction
The Massachusetts Water Resources Authority (MWRA) Lead Loan Program (LLP) provides a 10-year zero interest loan to municipalities to replace lead service lines within their community and or jurisdiction. The program has a reserve of 100 million dollars in available funding that can be distributed to various communities in the MWRA service area. The MWRA LLP was initiated in 2016 and the City of Somerville (CoS) utilized the loan program to conduct a first phase of lead service line replacement at various properties throughout Somerville. By engaging with its design consultant (Kleinfelder) and using available standards, record drawings, water maps and community outreach, CoS was able to identify 450 properties with lead service lines. The CoS Lead Service Replacement Program is broken up into various phases and will span several years. The paragraphs that follow provide the design concept and status of the program.
Design Concept
The program involves the full replacement of all lead from the water main to the meter located inside the basement of the property. All service lines will be replaced with copper lines typically ranging from ¾” to 1” diameter in size. The method of replacement involves a trenchless pull technique in which the contractor attaches the new copper service line to the existing line at the meter (located in the basement of the property) and then disconnects the existing service line. The contractor also digs a test pit at the curb stop (typically at the sidewalk) outside, in which the contractor removes the existing curb stop and disconnects the existing line. The contractor then pulls the existing line out while the new copper line is attached, so it’s simultaneously installed with minimal disturbances. A similar technique is done between the water main, and the curb stop. After the copper line has been pulled through, a new curb stop is installed, and the site properly restored. The contractor visually checks the connections to ensure that there are no leaks. Prior to construction, CoS, Kleinfelder and the contractor perform pre-construction site visits to determine the service line material at the meter inside the basement, collect pre-construction photographs, evaluate existing site conditions, determine any scheduling conflicts with the homeowner and establish discussions with the homeowner on the work involved and anticipated disturbances.
Typical schematic of water service line from water main to meter inside
basement of residential property
Current Status of Phase 1
The Phase 1 project originally included the replacement of services at 64 properties with suspected lead services but as the project advanced, site inspections revealed many of those services were copper, either in the basement or at the water main. This discovery led to more properties being added to the Phase 1 program. The project kicked off in April 2021 and was substantially complete in the Fall of 2021 with 58 properties having lead service lines replaced. The project was completed under budget and no change orders were issued. Significant coordination was undertaken between the City, contractor, and property owners to ensure replacements were done in the least disruptive manner and at a convenient time for residents. Property owners provided excellent feedback about the program and were thankful to get their lines replaced for no cost.
Meter connection in the basement
Final restoration of replacement
Lessons Learned from Phase 1
During construction, several of the excavations at the water main revealed service lines were already replaced with a copper. This revealed that there are discrepancies in the available records provided by the City and to correct this issue, future phases should include site investigations with test pits at both the water main and near the curb stop prior to service replacement. Determining the disposition of the service line material beforehand can expedite the construction schedule and sequence. Pre-replacement test pits can also facilitate the process of adding more properties to the project as CoS discovers lead services that were previously replaced.
Phase 2 Program and Future Phases
The City of Somerville is happy to announce that the Phase 2 project was bid and awarded to the same contractor that completed the Phase 1 project (Tim Zanelli Excavating LLC of Somerville, MA.) The Phase 2 project scope consists of 100 properties and is anticipated to start in the Spring of 2022.
Conclusion
The lead services replacement program provides the residents of Somerville an opportunity to replace their lead service lines and eliminate a potential hazard from their drinking water at no cost. This project provides a progressive step forward towards a safer drinking water supply for Somerville residents.
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