I will back Wade up on several points.
Though she is fairly beamy for 11' it is not a lot of boat.
3 knts is slow, and this is a huge issue if you need to go against a current. Also you will be working hard to get the 3 knots. My boat is 18' and it will cruise along at 4 knots with no effort, and go 5 for extended periods if I push it.
It will work fine for fishing on ponds, alone. If you try to do more you will soon be thinking "I need a different boat."
On the plus side this looks like a quick build, so you could build this and then build a different boat for the river and wider world.
Yachting, the only sport where you get to be a mechanic, electrician, plumber and carpenter