30-Jun-2011 -- Finding this confluence is easy, as there are signs on the road to the south and west, as well as a large monument. It has been noted that the monument is off by a several hundred meters, the actual confluence is to the southeast, in a rice field. Also note that the monument is on the wrong side of an irrigation canal. From the monument you must drive 2.5 kilometers back to the main road to cross the canal.
I arrived prepared to get my feet wet and wade into the field, however I met the farmer on the road and he wouldn't give me permission to do so. It is just as well, because I would have trampled his beautiful young rice plants. So I walked south along the ridge until I arrived at 40º North, slightly west of the exact location.