With all the rain we've had plus the ice, I think the rivers and water ways should be high enough in early spring, But doubtful in the summer with no rain.
It is possible in the winter and spring, but the water does get thin in the summer and fall. If you don't mind a little work, low water has it's advantages as Jeff's post pointed out. Low water exposed old bridge foundations.
We allow 4 hours to Quaker Bridge. That's probably long but we are sightseeing and do stop for a picnic.
Another place to start that always has good water is here, the Batsto River.