The parties sent a collaborative survey team to locate the mouth of the proper river, and to establish its headwaters. In 1798 the commission decided the southernmost portion of this boundary, from the mouth of the St. Croix to its source, which was determined to be the Chiputneticook Lakes. This commission did no work to finalize details of the border north of the lakes, which was described as running in a straight line north to the highlands separating the Saint Lawrence River watershed from watersheds draining to the south.