Those are powerlines above the river. Pull way back and you'll see the right of ways leading away from the river in each direction.
Google Earth shows the upper banks about 200 feet higher than the river. If you scan back where the bank drops off on both sides you'll see the power high tension power towers (why can't I remember what they are called?)
Power - Transport 
Google Earth shows the upper banks about 200 feet higher than the river. If you scan back where the bank drops off on both sides you'll see the power high tension power towers (why can't I remember what they are called?)