Second Avenue Subway Phase 2 (New York, New York)
Instrumentation Oversight Protects Century-Old Structures During East Harlem Tunneling
Second Avenue Subway Phase 2 extends the Q line north from 96th Street to 125th Street in East Harlem and adds three new stations at a construction cost of approximately $7 billion. The work includes soft ground and hard rock tunneling, shaft construction, controlled production blasting in a dense urban corridor, and protection of historic structures and active rail lines, executed across four major construction contracts with several third-party stakeholders. Emprise Concepts is part of the Project Management Consultant (PMC) team, which acts as an extension of the Metropolitan Transportation Authority to oversee project execution and manage day-to-day coordination between design leads, field contractors, and third-party agencies. Emprise serves as the Instrumentation and Building Protection Technical Lead on the PMC team, overseeing execution of the contractors’ instrumentation and building protection programs.
Project Information
Project Scope:
Extension of the Q line from 96th Street to 125th Street with three new stations, comprising soft ground and hard rock tunneling, shaft construction, protection of historic structures and active rail lines, and PMC oversight of three of the four major construction contracts.
Unique Features:
Protection of Structures Over a Century Old
Controlled Production Blasting in a Dense Urban Corridor
Ground Conditions Ranging From Soft Soils to Hard Rock
Monitoring Continuity Across Multiple Construction Contracts
Our Services:
Instrumentation and Building Protection Technical Leadership
Review of Construction Protection and Geotechnical Instrumentation Plans
Baseline Coordination and Compliance Verification
Transition of Monitoring Programs Between Contracts, Coordination of Data Transfer to the Owner Data Management System, Review of Weekly Instrumentation and Exceedance Reports
Total Construction Cost:
USD$7 billion
Emprise Personnel:
Instrumentation and Building Protection Technical Lead: Jacob Grasmick
Impacts & Benefits
Specification Compliance: Contractor instrumentation and building protection programs are checked against specification requirements through plan review, installation record review, and independent field verification.
Verified Data Quality: Routine independent verifications and data checks confirm that instrumentation readings reaching the Owner data management system are reliable enough to act on.
Proactive Risk Management: Weekly instrumentation reports and exceedance reports are reviewed so that ground and structure movements are addressed before they affect adjacent buildings or rail operations.
Continuity Across Contract Boundaries: Instrument and data transfers, overlapping work zones, and data compatibility between contracts are managed so that monitoring coverage is not interrupted when responsibility changes hands.
Project Gallery
Project Summary
Second Avenue Subway Phase 2 extends the Q line north from 96th Street to 125th Street in East Harlem, adding three new stations at a construction cost of approximately $7 billion. The Metropolitan Transportation Authority owns the project, and Emprise Concepts serves on the Project Management Consultant team under the AECOM/HNTB Joint Venture, overseeing three of the four major construction contracts. Construction includes soft ground and hard rock tunneling, shaft construction, and controlled production blasting in a dense urban corridor beneath and beside structures over a century old and active rail lines. Emprise is the Instrumentation and Building Protection Technical Lead, responsible for oversight of the contractors’ instrumentation and building protection programs and for continuity of monitoring across contract boundaries. The role has run since May 2025 and continues.
Project Writeup
As Instrumentation and Building Protection Technical Lead on the PMC team, Emprise Concepts oversees execution of the contractors’ instrumentation and building protection programs across the Second Avenue alignment. That oversight covers review of construction protection plans and geotechnical instrumentation plans, compliance checks, review of installation records, and coordination of baseline readings before construction effects begin. Emprise manages the transition of monitoring programs between contracts, including the physical transfer of instruments, transfer of historical data, coordination of overlapping work zones, and resolution of data compatibility between contract-specific monitoring systems. Data transfer to the Owner data management system is coordinated through Emprise so that readings from separate contractors arrive in a single usable record. Routine independent verifications, data checks, coordination meetings, and review of weekly instrumentation and exceedance reports give the MTA an independent line of sight on ground and structure performance during tunneling and blasting.
