The Tukituki River drains the eastern part of the central Ruahine Range. Its catchment (area, 955 sq. miles) lies between those of the Manawatu River in the south and Ngaruroro River in the north. It is made up of a number of separate rivers rising mostly in the main range, and all flowing across the Ruataniwha Depression. Of these, the Makaretu, Tukipo, and Tukituki have a confluence above Waipukurau, the Mangaonuku and Waipawa join above Waipawa, and the resulting two large rivers joining two miles down stream from Waipawa. In the first half of their courses the rivers flow nearly east-west across the grain of the country. After the confluence the Tukituki swings north-north-eastwards along the grain to flow into the sea on the southern shores of Hawke Bay.
Although in the early days of settlement the river was used by barges to transport goods as far as Waipawa, increased erosion in the headwaters has now made it very shallow right to the mouth.
The minimum measured flow was 150 cu. ft. per second in 1948, and the highest measured flood flow was 200,000 in 1938. In 1893 floods on the Tukituki River washed away the bridges at Tamumu and Patangata, as well as spans of the railway bridge at Waipawa. The river also flooded the township of Clive.
According to a legend two taniwha lived in a lake situated somewhere in the upper basin of the present Tukituki River. They fought for possession of a boy who fell accidentally into the lake and their struggles formed the Waipawa and Tukituki Rivers which drained the lake. Tukituki means “to demolish” and it is thought that this refers to the destruction of the lake mentioned in the story.
by Thomas Ludovic Grant-Taylor, M.SC., New Zealand Geological Survey, Lower Hutt.