Delaware Aqueduct Rondout-West Branch Bypass Tunnel – Newburgh, NY

  • New York City Department of Environmental Protection (DEP)
Project Value



Energy And Environment, Water And Wastewater


Engineering, Program/Construction Management (PM/CM)

We provide comprehensive Construction Management (CM) services for New York City’s Delaware Aqueduct Bypass Tunnel project located in the Mid-Hudson Valley of Lower New York. We have been the CM on the Project since construction began in January 2013.

Project Overview

The Delaware Aqueduct, in service since 1944, supplies upwards of 50 percent of New York City’s daily water consumption. The Bypass Tunnel project is designed to replace a leaking portion of the Delaware Aqueduct. The Bypass Tunnel is the most significant, capital construction repair project in the history of New York City’s drinking water supply system.

At 85 miles long, the Delaware Aqueduct is the longest tunnel in the world.

The new tunnel will bypass and cutoff a leaking section of the Delaware Aqueduct, thereby improving the reliability of the City’s water supply system. Construction of the new Bypass Tunnel began in 2013. The initial phase of construction included two, deep shafts in rock- one 900 feet deep and another that was 760 feet deep. Both shafts were completed ahead of schedule, in 2016.

Our Services

  • Planning and Pre-construction Design Evaluation Services which provided basis for the final design which will allow for the safe unwatering of the existing tunnel
  • Construction Management of shaft and TBM tunnel construction which resulted in shafts being installed ahead of schedule and under budget
  • Environmental Health and Safety
  • ISO 9000 Quality Assurance and Quality Control
  • Substantial Site Preparation component with suggestions to maintain tunnel spoils on site virtually eliminating offsite trucking
  • Close Coordination with NYCDEP Operations to maintain critical NYC infrastructure
  • Communication Coordination

Quick Project Facts

  • Largest and most complex repair project in the 180-year history of NYC’s municipal water supply
  • The Delaware Aqueduct Rondout-West Branch Bypass Tunnel (RWBBT) project will replace a portion of the 45-mile Rondout/West Branch tunnel section of the Delaware Aqueduct that connects the Rondout Reservoir in Ulster County to the West Branch Reservoir in Putnam County
  • Building and connecting a new 2.5-milelong, steel and concrete lined bypass tunnel, 600 feet below the Hudson River from Newburgh to Wappinger Falls NY. Two 30-foot diameter shafts with a 20 MGD dewatering pump station.
  • Will eliminate the 15- to 30-mgd leak from the existing 80 year old, 13.5 foot diameter tunnel that conveys approximately 50-60 percent of NYC drinking water from the Catskill Watershed
  • The last phase of repairs are scheduled to start in October of 2024.

Project Awards And Accolades

  • We received the DEP BEDC 2017 Award for “outstanding performance on the EHS Management System Audits and Implementation of Best Management Practices for Program Efficiency, Risk Control and EHS Culture
  • We received an Excellence Award in Construction Management from the NYCDEP in 2017. Our team developed a unique approach to connect the new tunnel to the existing tunnel, reducing time of the shutdown tunnel outage from 16 months to six months.
Groundbreaking Tunnel Innovation

We offer innovative solutions to some of the largest, most complex tunnel and underground construction projects in the world. Our experts are dedicated to overcoming the toughest challenges to help customers move safely under or through any obstacle. Learn more.

Be the first to receive updates about Parsons news, events, and innovations. Subscribe Today!

Back to top
facebook-pixel linkedin-pixel linkedin pixel focused image