Big UV in the Big Apple
Project Background
New York City, is made up of five boroughs: the Bronx, Manhattan, Queens, Brooklyn and Staten
Island and is home to more than eight million people, making it the most populous city in the United States.
The City draws its drinking water from two protected surface water systems: the Catskill/Delaware and Croton watersheds. The majority of New York City’s (NYC) drinking water is supplied by the Catskill/Delaware watershed, located approximately 100 miles outside the city. Historically, NYC has not filtered the water from this system nor did they require any additional barriers to microbial contaminants due to the pristine nature of the watershed. The total area of both watersheds is approximately 1,972 square miles and contains 19 reservoirs and three controlled lakes.
In 2006, the United States Environmental Protection Agency released the Long Term Enhanced Surface Water Treatment Rule (LT2ESWTR). This new rule requires surface water treatment facilities to either filter their water or install an additional barrier for microorganisms as a multi-barrier disinfection strategy. The city of New York needed to comply with the LT2ESWTR by 2011. Engineers working on the Catskill/Delaware project evaluated a new filtration plant but the cost of installing a 2.2 billion gallon per day (BGD) filtration facility was significantly greater than other alternatives. After evaluation of available technologies, it was decided that UV was the most practical and cost-effective solution.
The Trojan Solution
When completed in 2011, NYC will operate the largest drinking water UV installation in the world – the Catskill/Delaware UV Facility – with a capacity to treat 2.24 billion gallons per day (BGD). Combined, the Catskill/Delaware and Croton water plants will supply residents of NYC with over 2.8 BGD of high quality drinking water. In 2003, after evaluation of available lamp technologies, NYC chose to design a low pressure, high output (LPHO) lamp based UV system over a medium pressure (MP) lampbased system. The LPHO units are capable of disinfecting the water utilizing approximately one-third the power of MP lamp units. Trojan Technologies offered a high-flow capacity LPHO lamp solution – the TrojanUVTorrent™ – which minimizes electrical costs while maximizing disinfection efficiency.
Catskill/Delaware UV Facility
In 2005, Trojan Technologies was selected as the manufacturer for the UV portion of NYC drinking water project. In 2009 and 2010, Trojan delivered 56 TrojanUVTorrent™ UV units to the Catskill/Delaware UV Facility. Each unit is capable of delivering a 40 mJ/cm2 dose to 40 million gallons of water per day (MGD). This disinfection requirement, set by the NYC Department of Environmental Protection, delivers greater than 3-log reduction of microorganisms such as Cryptosporidium and Giardia. The TrojanUVTorrent™ was customdesigned by Trojan’s engineers and scientists in order to meet the challenging design parameters of this unique project.
The Catskill/Delaware UV Facility is located in Valhalla, New York. The treatment train consists of screening, UV treatment, and chlorination (for a residual disinfectant in the distribution system).
Croton Water Treatment Facility
In 2006, Trojan Technologies was selected to supply the UV equipment for the new Croton Water Treatment Facility. This facility has the capacity to treat up to 600 MGD of high quality drinking water. Trojan is supplying 20 TrojanUVTorrent™ UV units. Each unit is capable of producing a dose of 40 mJ/cm2 to treat a flow of 30 MGD.
For more information, please visit Trojan Technologies website at www.trojanuv.com