It seems like boaters are always willing to lend a hand, and occasionally that might mean towing someone back to the ramp when his or her boat has, uh, not lived up to expectations. For whatever reason, it won’t get them home. You have some choices to make. Of course, you want to help, but if you’ve got an 18-foot runabout with a 100 HP outboard and the boat that needs a tow is a 38-foot cruiser, the physics should indicate you’re not in a position to tow this boat anywhere. If there is a risk to human life, like if a boat is on fire, you are obligated to mount a rescue effort, but you are not required to preserve property.
There are legal implications to consider, but if you act as any prudent person would, you are somewhat protected from liability. So, as long as you don’t do anything stupid or reckless, odds are good you won’t get sued for trying to help someone. If you can’t tow someone, or are uncomfortable with your abilities, the best help you can offer might just be standing watch while waiting for Sea Tow or some other such service to arrive.
Towing a Boat on the Water: The Basics
There are also practical implications, namely, how to tow the other boat safely, so no one gets hurt and neither boat incurs damage. If you have a trailer boat and you’re pulling another boat of a similar size, then attachment points and rope types aren’t as critical. A good dock line from your stern cleat to the other boat’s bow eye or bow cleat should suffice. Bear in mind that pulling from a cleat on one side of your boat is going to make towing a bit clumsy. If you can pull from the tow eye on the center of your boat to the cleat at centerline of the towed boat, the tow will go much more smoothly.
That’s where a bridle setup will help, and the larger the boat you’re towing, the more necessary it becomes because you will need to spread the load among many attachment points because it becomes too great for one. If you don’t, you can snap cleats off, at which point they can become dangerous projectiles. Keep clear of lines under tension. If the cleat snaps, it traces the path of the line.
The U.S. Coast Guard Auxiliary has a good video on YouTube on how to make a simple bridle:
Each side of the bridle should be twice the beam of your boat, so figure about 17 feet for a typical trailer boat. Typically, your forward-most attachment points for the towing vessel will be your amidships cleats, passing the load to your stern cleats, which form the tips of the “Y” to form the bridle.
Use the bridle length and amidships cleats for the towed vessel, too. Just spread the load forward to the forward cleats, to form the Y of the towed vessel’s “Y.” Then put a stretch of line between the bridles. Because of the amount of load on this line, use knots that don’t tighten with tension, such as a cleat hitch or a bowline. The amount of line between the boats should be about eight to 10 boat lengths. So, if you’re pulling a 20-foot runabout, figure up to 200 feet of rope.
Of course, most people don’t carry that much line on board, so if you’re rendering assistance, allow for as much distance between the boats as possible. Also bear in mind that nylon ropes can stretch and snap. Good dock lines or an anchor line is probably your best choice.
While towing, you’re not going to be able to get on plane, which is probably a bad idea anyway. Just pull with a steady throttle, enough to keep ample tension on the lines. If you’re towing in rough water, that will be more difficult.
Rough water can be a challenge, but wind and current present their own challenges. It’s always best to tow upwind or upstream, if you can, because it gives the towing driver a greater measure of control.
We don’t always have that option, but realize that wind can push a towed vessel off course, so you have to maneuver the towing vessel accordingly. Likewise, current can push the towed vessel in ways the towing driver doesn’t intend. One thing that will help, when you get to your destination, is to tow the vessel to the dock or ramp upstream because of the greater control. If that means traveling downstream a bit and then back upstream, then do it. Currents can also help control speed when approaching a dock, to help the towing driver get the towed vessel to go where he or she wants it to go.
Realize, of course, that if you volunteer to help, it changes your day. What was supposed to be a relaxing day on the water can become stressful. Consider the size of the vessel, the distance of the tow needed and the circumstances before volunteering to become a tug boat captain. Sometimes the best option for those in distress is to let them call for professional help.
For more information, read Top Mistakes that Lead to Tow and our Boat Towing Guide: How to Trailer a Boat.
Editor's Note: This story was originally published on boats.com in June 2015 and updated in May 2018.