near the park's swimming area and beach was demolished, and a new building was constructed to replace it at a cost of about $2.3 million. The building incorporates changing facilities, restrooms and showers, a snack concession, and a meeting room. 2011 Master Plan and Environmental Impact Statement On March 23, 2011 the State's Office of Parks, Recreation and Historic Preservation published a "Final Master Plan/Final Environmental Impact Statement for Green Lakes State Park". The Executive Summary of the Plan notes: 1002 acres in the western half of the park is designated as a Bird Conservation Area. Approximately 105 acres in the Old Growth area within the National Natural Landmark, and the area surrounding Round Lake, is designated as a Park Preservation Area Improve the Rolling Hills Campground in the short term. In the long term the campground will be relocated to an area south of the park office. While the large white-tail deer population in the park is a problem, bow hunting is excluded; some local groups have called for bow-hunting of deer in the park as a partial solution. Geology and limnology Origin of the gorge The cliffs surrounding Round Lake are about high, but the rocky gorge in which the lake lies is much deeper than this. The bottom of Round Lake is about below its surface. Round Lake's bottom lies in sediments which may be another deep. There is thus nearly gouged out of the bedrock here. This deep gorge was formed towards the end of the last ice age, about 15,000 years ago, by an enormous river of water. The river originated in the melting, retreating ice sheet, and it flowed east through this channel on its way to the sea. The Niagara River gorge lying below Niagara Falls is an active example of this type of gorge formation; its depth is about , which is somewhat shallower than that at Green Lakes. There are several other similar gorges in the same region as Green Lakes State Park, in particular at Clark Reservation, at Smoky Hollow ( south of Clark Reservation), and at Pumpkin Hollow (about west of Clark Reservation). Geologists call these gorges and hollows "the Syracuse channels." Origin of the lakes Green Lake and Round Lake are probably the remnants of the "plunge pools" of enormous waterfalls that existed during this era. However, the presence of two distinct lakes is not fully understood. As