Frenchman's Flat Day Use Area provides vehicle access via Old Highway 99 with a 60-space parking lot (overflow parking available on roadside during peak periods April-October) and serves as the primary access point for Piru Creek recreation including swimming, fishing, and non-motorized trail use on the converted paved highway.

The site includes vault toilets, picnic tables, and trash facilities, though camping is discouraged; whitewater boating access is limited and constrained by dam release schedules and Forest Service motor vehicle regulations.