BNew York City currently relies on the two water tunnels for the majority of its drinking water. City Water Tunnel No. 1 was put into service in 1917 and City Water Tunnel No. 2 in 1936. City Water Tunnel No. 3 has been under under construction since 1970. City Water Tunnel No. 3 will provide New York with an alternative way to access clean drinking water. After the construction of City Water Tunnel No. 3, the Department of Environmental Protection (DEP) will be able to shut down the first two water tunnels for repair for the first time in history. The new tunnel will be over 60 miles long. The total project cost will be about $5 billion. There are four stages to the City Water Tunnel No. 3 project. Stage one of the construction starts from Hillview Reservoir in Yonkers, New York, crosses under Central Park in Manhattan to Fifth Avenue and 78th street, to East River to Roosevelt Island to Astoria, Queens. This stage is already completed and cost around $1 billion. Stage two has two sections: The Brooklyn and Queens section and the Manhattan section. The Brooklyn and Queens section begins in Red Hook, Brooklyn and connects to Richmond Tunnel in Staten Island, passing through Park Slope, Bedford-Stuyvesant, Bushwick, to Queens' Maspeth, Woodside, and finally connect to Astoria from stage one. The Brooklyn-Queens section is due for completion in 2018. The Manhattan section begins in Central Park, runs south along the west side of Manhattan to Lower East Side. At approximately 34th street, the tunnel forks east and goes north under Second Avenue to about 59th Street. The tunnel was completed in 2008 and opened for service in 2013. Stage three of the tunnel begins from Kensico Reservoir in Westchester to the Van Cortlandt Valve Chamber complex in the Bronx. Stage four of the tunnel will begin at Hillview Reservoir in Yonkers, pass through eastern Bronx, through Queens, and connect to stage two. The whole project is estimated to be completed by year 2020.