The West Road River or Blackwater River or Tiyakoh is an important tributary of the Fraser River, flowing generally north-eastward from the northern slopes of the Ilgachuz Range and across the Fraser Plateau in the Chilcotin region of central British Columbia, Canada. With only one major tributary, the Nazko River ("river flowing from the south" in the Carrier language), its confluence with the Fraser is approximately 40 km northwest of Quesnel. It forms the division between the Chilcotin Plateau (S) and the Nechako Plateau (N), which are subdivisions of the Fraser Plateau.