Waters from Tropical Storm Lee are seen here in the normally dry reservoir behind Indian Rock Dam September 8, 2011. To the left is the dam’s concrete overflow spillway. The water in the reservoir peaked at 44.1 percent capacity during Tropical Storm Lee. Had the reservoir’s capacity been exceeded, water would have flowed into the concrete spillway and made its way downstream so as to not risk putting too much pressure on the dam. Tropical Storm Lee caused devastating flooding in parts of Pennsylvania and other states, but in York its impacts were greatly reduced by Indian Rock Dam.