Based on the latest information available, the Rothwell Recreation Site boat ramp in Idaho is a concrete boat ramp that is approximately 25 feet wide. It provides access to the Blackfoot Reservoir, which is a 18,000-acre body of water located in Caribou County, Idaho. The reservoir is primarily used for fishing and recreational boating, including motorized and non-motorized watercraft such as kayaks, canoes, and powerboats. It is important to note that some restrictions may apply to certain types of watercraft, so it is recommended to check with local authorities before launching any boat.