7 spots where US-81 has less than 16 ft of clearance, in the order you drive them from south to north. The lowest is 13 ft 6 in in North Dakota, Main Avenue & 10th St-Fargo. 1 is under 14 ft and 2 under 15 ft.
Posted signs and your permit come first. These are the clearances states reported to the federal National Bridge Inventory in 2025. Repaving, snow and new work can lower them.
