Smith river inflows to Wolfeboro's back bay. It crosses Rte 28 about a mile north of Brewster Academy (heading toward Ossipee) , with the bridge over rte 28 right at the Wright Museum.
I do not know where the "upper dam" is located, but there is a dam right by that bridge.
Whitten Neck Rd is located a little further north of that location, cutting off to the right. If you go on Google earth, go to Wolfeboro, and then pan to the NE of Wolfeboro, and move the mouse pointer to 45.35*50*71N 71-11-43-53W is where the old railroad bed crosses Whitten Neck Rd (I think) and that would put the bridge location just below and to the right of that waypoint. ( I think).
gotta love technology
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