Not a problem right now - you get to learn the water and will pick your spots. 10hp used to be the standard in the river 20yrs ago. We're spoiled now with more power options but 10's are still okay.
I now run a 14' with a 9.9 merc and its okay. Highwater is the best to run in because hidden of the deeper water and the water is easier to move in. Once the water gets lower you start getting sections of much faster moving water that you are forced to go thru and that's when the little 10's start to struggle.
High water thru Pegleg no problem - low water thru Pegleg and its tough to make it thru.
A few years ago I ran a 12' tinny with a 8hp 4-stroke. With two big guys - that was slow but still okay in high water but I would not have even dared to go thru pegleg in mid August.
The thing with small motors is until you are sure about the boats capabilities or until you are sure of the water, travel upstream at the start of your trip. That way if anything happens or you get into water you can't handle, you know you can make it back to your truck. I always try start off by going upstream for safety sake.