(1) Description: A boat ramp or launch is a sloping, stabilized roadway or entry point constructed on the shoreline for launching boats from vehicular trailers or by hand. Ramps and launches extend into the water at a slope of typically twelve to fifteen percent and are typically oriented perpendicular to the shoreline. Ramp and launch widths vary with intended use, whereas the length often depends on the slope of the shoreline and seasonal water levels. Ramps and launches are usually constructed in areas protected from wind and waves with access to deep water close to shore; they are often associated with marinas and parking lots. Construction materials commonly consist of gravel, concrete, or asphalt.
(2) Fish life concerns: A boat ramp or launch typically destroys habitat that supports fish life in its footprint. A large number of ramps or launches in a given area reduces and fragments habitat. Ramps and launches placed above bed grade can block sediment and wood movement, and alter nearshore juvenile fish migration behavior. Ramp and launch construction, maintenance and the associated vessel activity can damage or destroy aquatic vegetation.
(3) Boat ramp and launch design:
(a) Design and locate ramps and launches to avoid adverse impacts to fish spawning areas.
(b) Design and locate ramps and launches to avoid or minimize excavation waterward of the OHWL.
(c) Design and construct ramps and launches to minimize interference with wood and sediment movement.
(d) Design the boat ramps and launches to prevent erosive undercutting or breaking of ramp edges.
(e) Design and construct boarding floats to minimize grounding on and shading of the bed and interfering with sediment and wood movement.
(4) Boat ramp and launch construction:
(a) Construct upland portions of ramps and launches in the dry and when the water body is at its lowest elevation or flow.
(b) Construct footings or the base of ramps and launches below the preexisting grade of the stream bank or lakeshore to minimize undermining the structure.
(c) Construct ramps and launches with concrete, compressed or hardened gravel, or other suitable materials approved by the department.
(d) When constructing concrete ramps and launches below the OHWL, use precast concrete slabs or isolate the wet concrete from waters of the state until it is fully hardened.
(e) Securely anchor launching rails to the stream or lake bottom.
(5) Ramp and hand launch maintenance: Whenever feasible, place sediment and woody material removed from ramps and launches at or waterward of the OHWL downstream of the structure.