Wakapuaka River

The coastal estuarine area is important for the mix of tree species that has developed over time and because similar areas have largely been lost elsewhere in Nelson due to land reclamation.
The geology of the area has been strongly influenced by the Waimea Fault, which extends from near Lake Rotoiti to Taranaki. Two distinctly different rock types, the “Brook Street Volcanics” and the “Maitai Group” are separated by the fault. Most of the Wakapuaka Valley is comprised of Brook Street Volcanics, which helps to produce the valley’s fertile soils. In comparison, most of the bedrock that underlies the Upper Wakapuaka catchment is the Maitai Group, which lacks volcanic debris and is less fertile.

The Wakapuaka River rises in the lowland hill country of the Bryant Range. The area is dominated by both production and protection forestry. There are three headwaters tributaries – the Teal and Lud rivers and Slaters Creek. The river then travels through the lowland hill country and emerges onto the lowland flats. Land use in this area is dominated by farming on the river flats with mainly production forest on the upper slopes, although some native forest remnants remain.

Below the confluence of the headwaters tributaries at Hira Village the river flows through lowland and coastal flats along with associated river terraces. Land use on the flats and terraces includes farming along with an increasing number of small holdings. On the mid slopes there are extensive areas of production forest and native forest remains on many of the upper slopes.

In its lower reaches, the river opens out into the extensive estuary of Delaware Inlet. The area includes Delaware and Pepin Spits, the Cable Bay / Pepin Island Boulder Bank, Bishops Peninsula and saline flats between. The coastal area is unique with a range of ecosystems including the Boulder Bank, estuaries, dunes and freshwater wetlands, enclosed by coastal hill country, flats and alluvial terraces.