google this longitude / latitude 42.35407, -71.25864
or google map this address 332 Islington Rd, Newtonville, MA
it's that area right to the NW of that point. i'm sure you know that thin stretch and the surrounding areas. it's like a small channel through the main river.
http://www.mafishfinder.com/view_photo_details.php?id=18715&pid=5