Why do high speed ferries go so slow

Factual Questions
1

This is rather specific, and I apologize upfront. But why does the SeaStreak ferry to NYC from Highlands/Atlantic Highlands go so slow. My best guess is it’s less than 20 miles and it takes roughly 55 minutes. This is supposedly a high speed catamaran ferry. While I’m not a mariner nor a marine engineer, if seems like we easily could go twice the speed. Is it fuel? FWIW, this is a pretty expensive way to commute.

Any anecdotes on what the fastest commuter ferries are?

Thanks.

2

For what its’ worth, Wikipedia says the SeaStreak catamarans travel “at a service speed of 38 knots (44 mph).” That’s about as fast as conventional ferries get (i.e. apart from hydrofoils and hovercrafts). The HSC Sea Runner has done 48 knots in trials but its service speed is listed as 37 knots.

3

Here is some data about the ferries that they use:

They list a service speed of 28 to 38 knots depending on the ferry, and a max speed of 30 to 42 knots. So while it seems to you that they could go faster, the ferries actually don’t seem to be designed for it.

I’m not a marine engineer either, so I can’t comment about where this limit comes from. I do know that many ferry speed limits come from the size of the waves that they create. They might be able to make ferries go faster, but they wouldn’t be allowed to operate them at faster speeds due to existing regulations, so they design the ferries for the maximum speeds where they’ll be used.

According to The Google, the world’s fastest ferry has a top speed of 58.1 knots (67 mph).

4

One reason to slow them down: Shoreline damage.

5

Other boats in the vicinity may force the ferry to slow down as well. I’ve been on the Tennessee Aquarium’s River Gorge Explorer excursion boat which has a similar top speed. It felt pretty fast, but it kept having to slow down to pass other boats.

6

The distance is a little over 20 miles, actually. 20 miles over 55 minutes works out to about 19 knots.

I would wonder whether the “38 knots” speed is only what the ferry does in the Lower Bay. Half the route is in the Upper Bay and the East River, where there’s a good deal more traffic to watch out for. Tidal currents might also rob you of a couple of knots of speed, depending on the time of day.