There is potable and non-potable rinse water available at a location approximately 30 miles East of St. Maries, Idaho. To get there, you can take Highway 3 North from St. Maries for less than 1 mile, then turn right on St. Joe River Road and continue for about 29.5 miles. Another option is to go 5 miles East of Calder on St. Joe River Road. This location is an RV dump station.
RV Dump Station
