Great Loop Tool
Bridge Clearance Worksheet
The famous low-clearance conversations are really about uncertainty. This worksheet helps capture the exact measurement, the removable gear, and the verification steps before a low bridge becomes a high-stress moment.
Clearance estimate
Measure these before believing the number
- Radar arch top
- Antennas up and down
- Anchor light
- Canvas and frame
- Solar mounts
- Dinghy davits if relevant
- Water tank full/empty effect
- Fuel load effect
- Published clearance datum
- Current gauge or lock/bridge notice
Worksheet habits that reduce bridge stress
Use this worksheet before you are idling in current near a fixed bridge. Fill it out at the dock with the crew calm, the boat measured, and the removal plan clear. If lowering antennas or canvas takes twenty minutes, that time belongs in the plan, not in a last-second scramble.
Keep a photo of the boat's highest points and a written list of what changes the measurement. Dinghy davits, solar panels, anchor lights, radar mounts, Wi-Fi gear, and temporary flag poles can all turn a remembered number into a bad number.
Before committing to a low bridge
- Check current water level or tide, then compare it to the published clearance assumption.
- Read local notices and recent cruiser reports for temporary restrictions.
- Assign one crew member to call clearance while another focuses only on boat control.
- Do not let schedule pressure override a measurement you cannot verify.
Worksheet mistakes
A clearance worksheet is only useful if the number is current and the crew believes it. Problems start when antennas change, a dinghy is added, solar is tilted, or someone remembers a height from a previous owner without checking how it was measured.
- Update the worksheet every time gear changes above deck.
- Record whether the number includes antennas, lights, flags, canvas, and radar.
- Avoid making low-bridge decisions from memory.
- Photograph the reduced-height setup so the crew can repeat it correctly.
Publication notes
Written and maintained by TheCenterOf editors. Last reviewed: 2026-07-06. This page is planning guidance for boating and Great Loop readers. It is not a substitute for current charts, notices, marina confirmation, weather forecasts, official rules, professional advice, or onboard judgment.
Corrections, broken links, and first-hand route updates are welcome through the contact and corrections page.
Official sources to verify
Use this page as a planning framework, then verify current details before making route, safety, insurance, customs, or departure decisions.