The Lewiston Pumped Storage Project is located next to the Niagara River, and is integrated with the larger Niagara Power Project. The Lewiston Pump-Generating Plant is the powerhouse for the pumped storage portion of the project, and lies between the upper reservoir and the lower reservoir, known as the forebay. The plant has 12 reversible turbine/pumps, which spinning one way, lift water 100 feet up into the upper reservoir, which holds 20 billion gallons, and covers three square miles. When water is allowed to flow back into the plant from above, the reversible turbines, called runners, rotate the other way, and produce electricity, adding around 240 megawatts to the grid during the day, when demand for power is high. The lower the forebay, holds two billion gallons of water and also feeds the adjacent Robert Moses Power Plant, a 2,000 megawatt hydropower plant directly on the river. The forebay is fed by a conduit which draws water at intakes above Niagara Falls, and runs under the city like a submerged river, for four miles.