Ohinekoao Stream
Works were undertaken to convey flood flows through the Ohinekoao Stream to provide better flood management and to protect the transport corridor.
The project will provide a stream channel for flood flows (and some debris), while reducing the height on the stream bank so that future debris flows can flow over the bank and towards the road and railway without significant obstruction. The path towards the campground has been blocked by adding to the earth buttress placed after the May 2005 event. The extended buttress was constructed to contain the expected level of debris in an event similar to May 2005.
On the fanhead, seaward of the railway and the highway, a debris bund has been constructed to prevent flow towards the campground as the debris flood spreads out on the flatter terrain.
The project includes:
- excavation of material from the right stream bank downstream of the escarpment to reduce the height and clear a path for future debris flows
- placement of material to increase the height and extent of the existing earth buttress on the right bank of the escarpment and form a debris control bund to direct the path of future debris flows
- a bund on the coastal flood plain to limit the extent of future debris flood spread to the left of the fanhead
- gabions to stabilise the stream banks and provide erosion protection in the reach flowing to the State Highway culvert
- new twin 5m by 2m high box culverts under the State Highway.
The Whakatane District Council component of the works have been completed.
New Zealand Transport Authority (NZTA) and Ontrack are still to install upgraded culverts.