Existing and proposed stormwater drainage and underdrain systems, including location, size and slopes of all pipes and swales, including invert and top elevations at each manhole, inlet, headwall or other appurtenant drainage structure; base width, side slope, inverts, and lining of each swale (riprap, asphalt, concrete, grass, etc.); and inverts of underdrain systems at bends and outlets. Roof drains and footing drain runoff shall be directed to an existing storm drainage system in the street, if possible, and not directed to adjacent properties. Underground detention of percolation systems may be required.