Last month, a Swedish company gave a demonstration of a boat they make designed with a hydrofoil hull. The company says it hopes to one day use this technology for a water ferry on the Potomac to Georgetown. While this is an impressive display, there are reasons to remain skeptical that we’ll see hydrofoil ferries anytime soon pulling up on the dock.
Hydrofoil hulls work by essentially bolting on a set of wings to the bottom of a normal boat. As the boat picks up speed, the “wings” (i.e. the foils) provide lift enough that the whole boat (minus the foils of course) rises up and out of the water. This has several advantages. For one, it significantly reduces the drag caused by the boat going through water, so higher speeds can be achieved with less energy spent. Additionally, (and more relevantly for Georgetown) the boat produces a far smaller wake because it is no longer having to push so much water out of the way. The video above demonstrates how small the wake is, despite the boat traveling over 18 knots (about 20 mph).
This would have the potential to dramatically reduce the travel times for a ferry to Georgetown. That’s because there is a “no wake zone” above Memorial Bridge. So any boat traveling from, say, Alexandria, has to spend the last mile creeping along at a very slow rate. If a ferry could cruise in to Washington Harbour at 20+ mph, it could significantly reduce travel times and possibly make it a more viable option for some.
But there are plenty of reasons to doubt this will actually happen.
First, we’ve been here before. Starting around 2010, a water taxi company operated a few routes to Georgetown (not the one that operates now). After a few seasons they closed down but promised to return with hovercrafts that would allow them to travel faster. They even had a demonstration of the hovercraft in 2013 at the exact same spot the hydrofoil was just shown. You’ll not be surprised to hear that the Potomac hovercraft never came to pass. (It’s probably telling that as I searched for a news report of the 2013 hovercraft demonstration, Google instead kept giving me news reports of this 2025 hydrofoil demonstration.)
Another concern is that it’s not quite right to say that there is a “no wake zone” above Memorial Bridge. There’s a speed limit, full stop. No boats are permitted to go over 6 mph. And this is not just pedantry. This part of the river is designed to host slow recreation boating, like kayaking, paddleboarding and canoeing. Throwing off a huge wake is bad and dangerous for these activities and is prohibited. But a boat going 20+ mph through here is also bad and dangerous for these activities even without a wake because a big fast boat can still injure or kill someone.
Maybe there could be remedial measures put in place to prevent that from happening, but I’m skeptical they’d be sufficient to limit the risk.
On top of everything, ferry-sized versions of these hydrofoil boats cost about $1.3 million. Is there enough demand from riders to justify that expenditure? We’ll see.
The Georgetown Metropolitan 