State officials said Thursday that they hope to sign a contract for reconstruction of the heavily damaged Lake Oroville spillway by April 17. “We’re working very fast,” said Bill Croyle, acting director of the Department of Water Resources, which is under intense pressure to get the spillway in shape before the start of next winter’s rainy season. Although Croyle said the department has to conduct in nine months design and construction work that would normally take several years to complete, he expressed confidence that it was possible.