The Waiohine River is located on the eastern side of the Tararua Ranges near Carterton, in the Wairarapa region of New Zealand's Lower North Island. It flows through an area of native bush and is known for its scenic character, offering paddlers a visually striking environment with untouched riverside vegetation.

The river is generally rated grade 2, making it accessible to novice and intermediate paddlers. The main runnable section covers approximately ten kilometres of whitewater. Because the river depends on rainfall to reach adequate levels, it is typically run during winter months when sufficient flow is present. Paddlers should check flow information before heading out; a dedicated hydroline for Wairarapa rivers (including the Waiohine, Waingawa, and Ruamahunga) is available at 083 220-669, using button 9 to fast forward to relevant information.

The overall character of the Waiohine is that of a single-channel river with waves and moderate whitewater set against scenic, bush-clad surroundings. Commercial operators offer guided trips on the river, including a helicopter access option that involves flying into the Tararua Ranges and paddling out, which reflects the relative remoteness of the upper sections. The river is also suitable for a relaxing scenic float, suggesting the grade 2 sections are not technically demanding under normal flows.

The Waiohine is often grouped with the nearby Waingawa River as a pair of complementary runs in the same area, both offering similar character and conditions. Paddlers planning a trip to the region can potentially combine runs on both rivers in a single outing.