On May 5, 2025, the NYC Dept. of Environmental Protection (DEP) DELAYED the repair & shutdown of the Delaware Aqueduct until after 2027 & new contract.

  ⇒ NYC DEP to Develop New Contract for Final Connection of Delaware Aqueduct Bypass Tunnel Following November's Project Pause (May 5, 2025, news release)

  ⇒ Get Delaware Aqueduct Repair Project Updates from DEP

Public Information:

The DEP will provide updates before, during and after the shutdown occurs, so everyone is aware of the project's status.

The DRBC will help share project information to Delaware River Basin stakeholders on this webpage and social, by email listservs and via its Regulated Flow Advisory Committee. Please check back for updates.

Background

The 85-mile-long Delaware Aqueduct is the world's longest tunnel. It transfers water from the three NYC Delaware River Basin Reservoirs (Cannonsville, Pepacton and Neversink) via the Roundout Reservoir to New York City. Roughly half of the city's population, plus other communities along the route, get their drinking water from this reservoir system.

The Delaware Aqueduct has been leaking upwards of 35 million gallons per day since the 1990s. In 2010, New York City announced a $1 billion plan to repair these leaks. After a decade-plus of coordinated, technical, engineering study, planning and modeling, the DEP will need to temporarily shut down the Delaware Aqueduct to complete the repair.

In the months preceding the shutdown, the NYC Delaware Basin Reservoir levels will need to be lowered. The fall timing to start the repair was chosen because demand for water is at its lowest. During the shutdown, DEP will not be diverting water from these reservoirs for water supply; however, they will continue releasing water into Delaware River tributaries pursuant to the Flexible Flow Management Program, a water allocation agreement between the states of New York, New Jersey, Pennsylvania and Delaware and the City of New York.

Project History:

• The shutdown - the final phase of this multi-year, billion-dollar+ project to repair leaks in the aqueduct - was originally slated to begin in October 2022, but was pushed back one year to 2023.
  
  
• In June 2023, the project was again pushed back one year, to October 2024.
  
  
  • View DEP News Release Announcing the Project Delay (issued June 28, 2023)
    
    
  • In October 2023, DEP temporarily shut down and partially dewatered the Delaware Aqueduct for 3 weeks as part of planned testing in preparation for the scheduled Oct. 2024 - May 2025 shutdown to repair leaks. 
    
    
• In June 2024, DEP began lowering NYC Delaware Basin Reservoir levels in advance of the aqueduct shut down. The shutdown was initiated in October 2024 and planned to go until the spring of 2025.
  
  
  • Mayor Adams Launches Final Phase of Historic Project to Secure Future of New York City's Water Supply (September 30, 2024, news release)
    
    
• In November 2024, the shutdown was paused due to drought conditions.
  
  
  • Mayor Adams Elevates Drought Level to Warning, Pauses Delaware Aqueduct Repair Project, Orders City Agencies to Implement Water-Saving Measures and New Yorkers to Continue Conserving Water (November 18, 2024, news release)
    
    
  • Following Significant Upstate Rainfall, Mayor Adams Downgrades City Drought Posture From Warning to Watch; Significant Rainfall in Watershed and Melting Snowpack in Mountain Regions Greatly Improved Reservoir Storage Levels - Pausing $2 Billion Delaware Aqueduct Repair Project Enabled DEP to Optimize Flow, Enhance Water Supply Flexibility to Meet City Water Demands (December 16, 2024, news release)

NYCDEP Webpage

• The Delaware Aqueduct Repair Project and its Impacts on Watershed Communities (NYCDEP webpage)

Project Factsheet

• Fact Sheet: Repairing the Delaware Aqueduct (pdf)

Presentations Given

• Delaware Aqueduct Repair Project Update (Jennifer Garigliano, NYCDEP; pdf - presented at 4/29/24 RFAC meeting)
  
  
• Delaware Aqueduct Shutdown Analysis (Amy Shallcross, P.E., DRBC; pdf - presented at 4/29/24 RFAC meeting)
  
  
• Delaware Aqueduct Shutdown Analysis (Amy Shallcross, P.E., DRBC; pdf - presented at the 5/11/23 Public Info Session)
  
  
• Delaware Aqueduct Repair Update (Jennifer Garigliano, NYCDEP; pdf - presented at 4/26/23 RFAC meeting and the 5/11/23 Public Info Session)
  
  
• Delaware Aqueduct Shutdown Analysis (Amy Shallcross, P.E., DRBC; pdf - presented at 4/26/23 RFAC meeting)
  
  
• Delaware Aqueduct Repair Update (Jennifer Garigliano, NYCDEP; pdf - presented at 6/29/22 RFAC meeting)
  
  
• Delaware Aqueduct Repair Update (Jennifer Garigliano, NYCDEP; pdf - presented at 3/23/22 RFAC meeting)

NYCDEP Contact

• NYCDEP Bureau of Water Supply Director of Outreach John Milgrim: jmilgrim@dep.nyc.gov

DRBC Contact

• DRBC Director of External Affairs and Communications Elizabeth Brown: elizabeth.brown@drbc.gov