Float the stone blocks on a wooden raft, dig a ditch from the river leading to the site. Build a lock at the end of the ditch, with wooden sides up to the height you're working. Fill the lock up with water from the canal, using buckets until the blocks are up to the level you're working. Repeat the process with more stone blocks until they're all up there. For the next layer, build the lock up higher. Repeat until you're done.
Primitive, but I suppose it's possible. Easier than building a dirt ramp and dragging the blocks up to needed level? I dunno.