Marlborough, MA
Massachusetts Water Resource Authority, Walnut Hill Treatment Plant, Cosgrove Intake Pipeline
Scope/Solutions
The Cosgrove Intake pipeline, a 144 in. dia. prestressed concrete cylinder pipe (PCCP), at MWRA’s Walnut Hill Water Treatment Plant Project was completed in early 2004 as a part of the water supply system for the City of Boston. Less than a year after construction of the pipeline, a large leak of approximately 700 gpm developed near a deep manhole chamber in a section of the pipeline with multiple elbows. SGH provided emergency response and evaluated the risk of failure resulting from the leak, inspected the pipeline to determine the cause of the leak, and developed a repair scheme.
For this project, SGH:
- Performed internal inspection of the leaking pipe using a diver during a brief shutdown while the line was in operation
- Evaluated the structural safety due to the combined effects of internal pressure, dead loads, prestress, and hydraulic pressure-induced thrust at elbows
- Internally inspected and measured all harnessed joints to determine if any joints opened more than the design limits, inspected the pipeline for visible signs of anomalies, and externally inspected the leaking joint
- Designed repairs that included welding of the leaking joint and soil grouting.
Project Summary
Solutions
Repair & Rehabilitation
Services
Structures | Advanced Analysis
Markets
Infrastructure & Transportation
Client(s)
Barletta Heavy Division
Specialized Capabilities
Repair & Strengthening | Buried Infrastructure | Failure Analysis
Key team members


Additional Projects
Northeast
Beach Street Garage
SGH has assisted the garage’s owners and property managers for many years by performing periodic condition assessments of the structure and developing plans for future repair and maintenance work.
Northeast
Prudential Center Parking Garage
The below-grade, cast-in-place concrete parking garage was constructed in the 1960s. SGH has led several projects, including condition assessments and concrete and waterproofing repairs for the parking garage structure, the plaza level, and roadway structures at Ring Road above.