Just askin'...

Why no river travel or exploration by waterway? The knowledge of how to make a canoe, bowl boat or even a raft cannot be lost to the survivors in the wasteland. A group of people who can take two (similar) mediocre weapons, take them apart and recombine them into a better weapon certainly has retained the knowledge of basic 101 boat building. The North American continent is laced with connecting waterways from Pittsburg to Boulder City and a good many other places besides.

Why would they concern themselves with traveling? Well because it's the nature of the beast. Anthropologists suggest exploration (curiosity) is a survival trait, perhaps even hard wired in the human brain . Person(s) are going to want to know what's around the bend or the other side of the hill and the only way to find out is to go and look. Is there a settlement that is doing great? Is there some group who has goods to trade? Is there a group of hostiles that might be threatening the future of your home? There is going to exploration! So why not the rivers (which would run clean in a short time) where settlements are going to gravitate to because of the clean water.

This isn't some pie in the sky scenario. Peoples native to the North American continent did exactly that before Europeans came and the Europeans followed suit establishing settlements, trading posts and relations with the tribes. By expanding the knowledge of the geography and all that it entails, expansion was made possible. The fact that there are hazards and loss of life has never deterred exploration over a long term. Ultimately man is going to learn more about his environment, and knowledge is power! The powers to survive, the power to be safe, to reproduce (Biggie), and have your offspring survive.

The scavangeable materials are in abundance in some areas and exist in nature in others. Rubber tires in post urban areas would make a platform for planks and then you have a raft. An airplane wing with the underside cut out could be made into a canoe with a keel attached for steerage (aluminum alloys float very well). Anyway I'm no engineer but if people 5,000 (or more) years previous could find a way to use watercraft there is no reason why post-apocalyptic man could not. So just askin'? Sorry this post was so long.

Uhhhm......Mirelurks?

Seriously though, it's more of a development thing rather than the people not knowing how to build/ use a boat. Actually Point lookout DLC uses an old river boat, so it's not like their unaware of traveling by means of rivers/ water ways(oceans).

Tenpenny said he came to the states from over seas, most likely by boat. So really the use of boats is indeed in the game/lore. We don't get to hop in a canoe and paddle away most likely because of how little the player would probably end up using it.

Why waste previous dev time on something that would go, for the most part, unused?

Don't you use a boat or raft to get to the Legion Stronghold?

There is the raft to the fort as mentioned and the River Boat to Point Lookout as well as the Oil Tanker in Fallout 2.

but mire lurks can't attack in water in fact it's probably safer than land they really should fix that next game

It's a dev thing, It'd be too much development time for something so small.

Agreed in Fallout 3 and in New Vegas I just use the water ways to swim around to alot of locations, it's like a highway but with no enemies attacking. Feels like Cheating sometimes but when I am in a rush to get to a location it is easy to do.

Hmm.. good points all. I suppose of I was thinking more of future games. Implementing river travel would require bigger maps but I don't see that being impossible. A story, quest(s) that would make sense to use that mode of travel. Maybe just the primary leg(s) of a journey to the west. Remember just getting to the Mississippi River would be going west a great distance if one started in Pittsburg for example.