• Corporate HQ, NY
  • Melville, NY
  • Iselin, NJ
  • Ossining, NY
  • Mount Laurel, NJ

Cat-Del Aqueduct Interconnection at Shaft 4


The Catskill and Delaware aqueducts carry about 1 billion gallons of water per day to New York City from six reservoirs in the Catskills. HAKS is providing construction management services to the New York City Department of Environmental Protection (NYCDEP) for a $25 million project to connect these two aqueducts, as part of the NYCDEP’s Water for the Future Program, which aims to provide clean, safe and reliable water.   The interconnect project is taking place at the Delaware Aqueduct's Shaft 4, where the two aqueducts cross, and will allow up to 365 million gallons per day to be moved from the Delaware to the Catskill Aqueduct. 

The interconnection will enable the NYCDEP to reduce the use of water from the Catskill Aqueduct during periods of high turbidity (cloudiness or haziness; a key test of water quality) caused by heavy rainstorms. This will reduce the need for chemical water treatment while maintaining high-quality water without filtration. It includes a major underground structure featuring large-diameter piping, flow metering, and pressure-reducing valves. The interconnection was designed to be below ground in order to preserve the agricultural environment of the site and minimize the creation of impervious surfaces that increase stormwater runoff.