Reconstructing New York City's Gilboa Dam

The 84-year-old Gilboa Dam that impounds Schoharie Reservoir is a key component of the New York City Department of Environmental Protection’s (NYCDEP) water supply system. This system serves approximately 8 million people in New York City and 1 million people upstate, delivers approximately 1.2 billion gallons of water per day, and is arguably the largest gravity fed, unfiltered, water supply system in the world. The Schoharie Reservoir accounts for approximately 15% of the water delivered by this system. In 2004, the NYCDEP embarked on a program to completely renovate and update Gilboa Dam. The NYCDEP, along with its design team, a joint-venture of Gannett Fleming and Hazen and Sawyer, has navigated through a maze of technical, operational, environmental, public involvement, and regulatory permitting issues, and is now in the early stages of construction. This article describes the evolution of the project and the measures taken to renew this facility for the next 80 to 100 years of operation. 9 pp.