Bridge Clearance Lookup
Enter your air draft and check 927 charted US bridges. See which spans you clear, find the ICW bridges under 65 feet, and for 49 drawbridges get the opening schedule and how to request an opening.
Measure to your highest fixed point: antenna, mast, hardtop.
Clearances are from NOAA charts, each measured to its chart’s datum: usually mean high water on tidal waters, IGLD 1985 on the Great Lakes, and a local datum on some rivers, lakes and canals. Each bridge’s page names its datum, and where a bridge’s spans differ, the lowest charted one is shown. Real clearance drops whenever the water stands above the datum, and the bridge’s own clearance gauge shows the least clearance. This is a planning estimate, not a guarantee, confirm at the bridge board and by VHF before passing.
Pathr nautical charts
Explore bridge clearances on the chart
Find the bridge and its charted vertical clearance in one view. Select a pin to compare nearby bridges, see open and closed clearances where charted, and open its operating details.
Bridges under 65 feet
Fixed spans charted between 55 and 66 feet, the ones a tall sailboat or sportfish needs to know about. Lowest first.
Drawbridges with opening schedules
Movable bridges with US Coast Guard operating rules and closed clearance.
Browse bridges by state
How to read bridge clearance
Vertical clearance is the height between the water and the underside of a bridge. On most US tidal charts it is referenced to mean high water (MHW); on the Great Lakes it is IGLD 1985 and on some rivers, lakes and canals a local datum, which each bridge's page names. The real clearance is lower whenever the water stands above that datum, as near high tide and during storm surge. Compare it to your boat's air draft (waterline to the highest fixed point, antennas included) and keep a safety margin.
A drawbridge (bascule, swing, lift, or pontoon) opens for vessels that can't clear it closed. To request an opening you hail the bridge tender on VHF-FM (Channel 9 in Florida, often Channel 13 elsewhere), sound the required horn signal, or call the posted number. Many drawbridges only open on a schedule or need advance notice, all set by the US Coast Guard in 33 CFR Part 117. Each drawbridge page here shows its specific rule where one exists.
Clearances come from NOAA S-57 electronic charts; drawbridge schedules come from the Coast Guard regulations. Both are references, not a substitute for the posted clearance gauge and current chart. When in doubt, wait for the tender.
