Drawbridge schedules and when bridges need not open

Navigation Rules, lights & bridges · Power & sail

The general rule is that a drawbridge opens promptly and fully on signal (33 CFR 117.5). Many bridges have their own schedule, advance-notice rule or closed periods, listed by state and waterway in 33 CFR part 117, subpart B. Those entries override the general rules.

Finding a bridge's rules

• Subpart B lists drawbridges by state, then by waterway in alphabetical order. Under each waterway, bridges run from the mouth upstream; the Atlantic ICW runs north to south and the Gulf ICW east to west (33 CFR 117.51).
• Where a subpart B entry differs from the general rules in subpart A, the entry governs; the rest of subpart A still applies (33 CFR 117.1(c)).
• Each subpart B bridge must post a sign upstream and downstream summarising its rules. If advance notice is required, the sign gives the name, address and phone number to call (33 CFR 117.55).
• NOAA's Coast Pilot reprints part 117, including the bridge entries for its region (Coast Pilot 7, 2026 edition).

Schedules and advance notice

• Some bridges open only at set times. Many Florida Atlantic ICW bridges, for example, open only on the hour and half-hour, or at quarter past and quarter to the hour, some all day and some only during set hours (33 CFR 117.261).
• Some bridges open only on advance notice; the tender then opens at the requested time and allows for a reasonable delay in your arrival (33 CFR 117.40).
• Some bridges are remotely operated or automated, and some are left open except when trains cross; their procedures are in subpart B (33 CFR 117.41, 117.42).

Openings outside the normal schedule

• A drawtender must take all reasonable measures to open, regardless of schedule, for public-safety government vessels, vessels in distress where delay would endanger life or property, commercial rescue or salvage vessels, and vessels seeking shelter from severe weather (33 CFR 117.31(b)).
• During floods, freshets or damage to a bridge or its fenders, the District Commander may require a listed bridge to be tended full time and to open on signal (33 CFR 117.59).

When bridges need not open

• During natural disasters or civil disorders declared by the authorities, unless subpart B or the District Commander says otherwise (33 CFR 117.33).
• During temporary schedule changes approved by the District Commander, which are announced in the Local Notice to Mariners and the Federal Register (33 CFR 117.35).
• During emergency repairs; the District Commander notifies mariners through Broadcast and Local Notices to Mariners (33 CFR 117.36).
• Bridges authorised to stay closed and untended because openings are seldom requested are identified in subpart B (33 CFR 117.39).

The rules: 33 CFR 117.1 · 33 CFR 117.5 · 33 CFR 117.31 · 33 CFR 117.33 · 33 CFR 117.35 · 33 CFR 117.36 · 33 CFR 117.39 · 33 CFR 117.40 · 33 CFR 117.41 · 33 CFR 117.42 · 33 CFR 117.51 · 33 CFR 117.55 · 33 CFR 117.261 · 33 CFR 117.59

A plain-language summary of federal rules for recreational boats, checked against the rules’ own text and a second source, and written in our own words. It isn’t legal advice. States add rules of their own, and rules change — the links above go to the current official text.