Chapter 105 requires persons proposing obstructions or encroachments to streams, their 100-year floodways, wetlands or other bodies of water, to first obtain a written permit. Obstructions and encroachments are structures or activities that change the course, current or cross-section of streams, 100-year floodways, wetlands or other bodies of water. Delegated by the Pennsylvania Department of Environmental Protection, ACCD reviews and issues General Permits GP-1 through GP-9 under the Chapter 105 Dam Safety and Waterway Management program. Chapter 105 General permits require a reviewed and approved E&S plan per permit conditions and 105.13(e).