How ferries work in the United States
There is no national ferry timetable in the United States. Every crossing is published by whoever runs it, and that is rarely the same body twice.
A crossing may be operated by a state department of transportation, a county road commission, a port district, a transit authority, a national park, a tribal government or a private company holding a franchise. Each publishes its own schedule, in its own format, on its own calendar. Some post a PDF once a season; others run a live vessel tracker. That fragmentation is the reason a single page per crossing is useful: the timetable, the fare table and the landing address end up in one place instead of three.
Fares follow the same pattern. A passenger fare and a vehicle fare are usually separate, the driver is sometimes included in the vehicle fare and sometimes not, and vehicles are charged by length band rather than by type. Where a crossing is free, it is normally because it forms part of a numbered highway and the state maintains it as road.
Time zones matter more here than in most countries. A reader in New York planning a crossing in Washington State is four hours away from the schedule they are looking at, and the boundary between zones does not follow state lines cleanly. Every timetable on this site is shown in the time zone of the departure landing, labelled with the zone in force on the day you are reading it, so daylight saving is handled rather than assumed.
Seasonality is the last trap. Many crossings run a full schedule in summer, a reduced one in winter, and stop entirely when ice closes a channel. Where a service is seasonal, the page says which season it is publishing and the dates that season covers.