140-Year-Old Manhattan Water Main Rehabilitated Through Trenchless Methods
In “the city that never sleeps,” it seems only righ t that any construction job match the moniker of Manhattan. For the past two years, workers from contractor Halycon Construction and subcontractor Insituform Technologies Inc. have convened on different blocks of iconic Madison Avenue, to rehabilitate a 140-year-old 48-inch water main runn ing under the street. To alleviate the headaches th at could happen by snarling New York City’s rush-hour traffic, workers quickly moved onto sections of the avenue each Friday night and worked until Monday morning. Just in the time of a weekend, the workers can fix between 500 and 1,000 feet of the existing main. To understand how old the problematic 48-inch water main is, envision the Brooklyn Bridge under construction, Jesse James robbing a bank or Civil W ar hero Ulysses S. Grant as President of the United States. All were occurring at the same time New Yor k City put in the water line. The cast iron pipe served the city for about 100 years, until the 1970s when it went out of service fo r being leaky and troublesome. Forty years after being decommissioned, a stretch of the water main that runs from East 40th Street to East 79th Street on Madison Avenue, is getting a unique overhaul. Deciding on Rehabilitation New York City’s Department of Environmental Protect ion (DEP) and Department of Design and Construction (DDC) decided to evaluate new technologies for rehabilitating water mains. With the heavy demand on New York’s streets, the city chose to use HDPE pipe and Insituform’s InsituGuard® installation process to lessen the time lanes of traffic would be closed to construction. “The city decided to use HDPE for various reasons, which I venture to say are because it has no advers e effect for potable water use, its durability and the ability to implement a trenchless replacement method for the old cast iron main in its water system,” said Jose Sanchez, resident engineer for the D DC. “As the installation of this type of pipe goes, it (the process) is clean and less intrusive.” Some older methods for rehabilitating the pipe would have been a nightmare. “Open-cut methods would take six months (for a 1,00 0-foot-length installation),” said Christian Onyech i, engineer-in-charge of the Manhattan Infrastructure Division of DDC. “The complete rehabilitation of the (Madison Avenue) line would take decades.” Other concerns come into play when dealing with New York City’s underground. Amazing amounts of conduits, pipes and other infrastructure can be fou nd just under the pavement. Surgically picking |