This second route served two major purposes, as it enabled Treffry to develop Carbeans and Colcerrow granite quarries in the upper valley, and was also used by a leat carrying water to supply the mine at Fowey Consols. Two further granite quarries, known as Rock Mill and Orchard, operated lower down in the valley. In 1870 these were linked to Pontsmill by a third tramway along the valley floor.
This secondary path served two primary functions, as it allowed Treffry to establish Carbeans and Colcerrow granite quarries in the upper valley, and was also utilized by a leat conveying water to supply the mine at Fowey Consols. Two additional granite quarries, known as Rock Mill and Orchard, operated lower down in the valley. In 1870 these were connected to Pontsmill by a third tramway along the valley floor.