 Today, Niagara is still the largest electricity producer in New York state, with a generating capacity of 2.4 GW.Up to of water a second is diverted from the Niagara River through conduits under the city of Niagara Falls to the Lewiston and Robert Moses power plants.Currently between 50% and 75% of the Niagara River's flow is diverted via four huge tunnels that arise far upstream from the waterfalls.