There is potable water and non-potable rinse water available at the RV dump station located at I-93 Exit 36. To get there, you need to take Route 3 North and continue on Route 3 until you reach Route 115. Then, follow Route 115 to Route 2, and from there, take Route 16 to Route 26. Finally, continue on Route 26 for about 7 miles until you reach Umbagog Lake State Park, where the RV dump station is located.
RV Dump Station
