A commercial use authorization (CUA) allows an individual, group, company or other for-profit entity to conduct commercial activities and provide specific visitor services within a national park unit. The National Park Service issues CUAs to manage a wide-range of commercial visitor services in addition to road-based commercial tours. At Lake Mead National Recreation Area this includes guided kayak trips, scuba diving classes, fishing trips, boat services, and much more. Current CUA Directory. Application Procedures.