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
MWRA Deer Island Wastewater Treatment Plant, Egg-Shaped Digesters
Buchart-Horn, the Electric Boat Division (EBDiv) of General Dynamics, and Perini retained SGH to develop the seismic design for egg-shaped digester tanks and their supporting concrete structures.
Northeast
99 Summer Street Parking Garage
The parking garage, constructed with concrete slabs on metal deck supported by steel beams and columns, includes two below-grade levels under a twenty-story office building. SGH performed a condition assessment and designed repairs to extend the useful life of the parking structure.