You can always refer to nautical charts and hopes that the bridge you are looking at is listed or if you have a more sophisticated electronic system (chart plotter) it should be listed. The main thing we are all looking at is whether we can safely clear the bridge (vertical clearance) or do we need to request an opening.
Captains should consult your charts for the note on heights whenever they are available; most charts will show minimum vertical clearance at mean high water. OK, what does mean high tide mean – right? Well that means, if you are at the bridge at any time other than high tide, you should have more clearance than shown. You should, prior to planning a trip, consult any cruising guides or a sailing forum such as www.sailblue.net for the area you will be traveling and make notes in your trip log concerning bridges including the name of the bridge, hours of operation, recommended method of contact, (channels) etc.
When you approach a bridge there are several thing that you should keep an eye out for. On the right side of the bridge should be the “clearance board”. This sign will give you the minimum clearance, in feet, from the current water level to the bridge structure. This allows you to determine if you can safely clear the bridge.
You should know the vertical clearance of your sailboat before you ever plan a trip! Do not cause unnecessary openings of bridges, it is illegal and you will get fined! According to the U.S. Coast Guard regulations, you may be subject to both criminal and civil penalties for causing an unnecessary bridge opening because of “any nonstructural vessel appurtenance which is not essential to navigation or which is easily lowered.” So if you are requesting an opening because of your mast height your are fine, if you are requesting an opening because you are too lazy to lower your VHF antenna or out riggers, well expect a visit shortly after passing from the coast guard. These same regulations also provide penalties for any bridge tender who “unnecessarily delays the opening of a drawbridge after the required signal has been given.”
Once a bridge is open, always slow down and use caution when navigating through the bridge opening. You might not be able to see if another boater is coming until they dart out into the bridge channel.
When you approach a bridge look for a blue sign with what looks like a telephone receiver with a lightning bolt through it. This gives you the radio frequencies that the bridge monitors. The channels are usually 16, 13 or 9. Proper protocol in most areas is to contact the bridge operator by VHF radio to request an opening; however, there is also a sound signal that can be used. To sound signal a bridge use one prolonged blast followed within 3 seconds with one short blast. The bridge tender will acknowledge an OK with the same signal. If the bridge operator cannot open at the moment they will signal you back a NO by sounding five short blasts. If this should happen you need to respond to the bridge operator with the same five short blasts back letting them know you understand.
You should know the name of the bridge you are contacting, here in southern Florida, bridges can be close and several are in range of your radio transmission. Dont call out “bridge, bridge, bridge.” I have found that bridge tenders can sometimes be a little cranky. (Now that being said I have had some really great tenders who have been awesome, thanks to all for putting up with us sail boaters.). If you know the bridge opens on demand dont make it sound like a demand ask nicely and make their day, I usually call the bridge on the radio and ask when the next scheduled opening is. If it is on demand, the bridge tender usually says “come on up Captain, I’ll open when you get here.”
Once at the bridge you will also find a white sign that shows the hours of operation. You should note that some bridges will open on demand year-round and some will only open on demand during certain parts of the year. In areas like South Florida, the boating population grows significantly in the winter time, and many bridges open only every half hour during the peak season.
Caution: Bridge structures make a great place to set up a marine speed trap, keep an eye open for other signs on the bridge rails such as speed and caution warnings.
When you approach a bridge at night you should see three red lights in a triangular pattern. These lights have a meaningThe two lower lights indicate the bridge opening just above water level. The center light hangs from the center of the bridge span. You should line up with the center light and keep the relative relationship of the lower lights equidistant on either side you to ensure you stay in the center of the passageway and the highest point of the bridge.
Once the Bridge is open and you passing remember steering is slow to react at slow speeds and use caution around other boaters. Also once you are through and back up to speed its always nice to throw a thank you back to the bridge operator via the radio and maybe with a few more polite and courteous people on the water, we can help keep our passage ways friendly.