It runs south for 30 kilometres from its headwaters west of Mount Owen in Kahurangi National Park to its confluence with the Buller River just below the town of Murchison.

[1] Downstream from Lake Matiri the banks of the river has mixed livestock farming and some small scale forestry.

It has a tight grade III rapid in a narrow cleft of a gorge a short distance upstream of the road end.

[4] A tramping track that starts at the road end runs along the western side of the river.

New Zealand Energy Limited have proposed the Matiri Project hydroelectric power scheme on the river.