16-Jun-2005 --  This confluence is in the ocean, approximately 7.5 km
from land.  This visit was to the coast near the confluence
and is therefore incomplete.
According to my GPS, I visited the point
41°57.526' N, 140°55.684' E, and the confluence
is 7.52 km away, at an azimuth of 52°.  This may be
the closest point on land to the confluence; at any rate,
the distance appeared to be a local minimum on my GPS.
This point is on the northeast coast of southern 
Hokkaido, about a 90-minute bus ride from Hakodate. 
It is very close to the intersection of routes 980 
and 278; it is also near the Ofune C dig site.  
This portion of the coast is dotted with fishing towns.