Marlborough Hydraulic and Ecological Stream Realignment

The Wairau Valley in Marlborough boasts a wealth of heritage and ecological treasures. PDP were engaged to design the realignment of a stream situated within a vineyard section of the Wairau Valley. Birch Hill Stream is the main watercourse on the property and flows from west to east.  The stream is intermittent, with two further intermittent streams joining it on the property before it flows into the Wairau River.  The two intermittent tributary streams are fed from the hills on the southern boundary of the site and two marsh wetlands were also confirmed on the site, fed by the intermittent streams. Historically, agricultural land use provided stock with access to the wetlands and streams. 


Malborough Hydraulic and Ecological Stream Realignment

PDP designed the realignment of the stream such that conveyance was maintained whilst ecological provisions were enhanced, and the available area for vineyard planting was maximised. PDP undertook a hydraulic modelling and ecological study to represent the existing environment and subsequently, the developed alignment where stream conveyance was maintained or increased, in addition to showing ecological enhancement. Enhancement work along the realigned reach included a meandering form, clustered riparian planting to provide shading to the stream, and improved instream habitat features such as pools, riffles, and boulders for refuge.



Wilkes Resource Management Solutions Ltd

Malborough Hydraulic and Ecological Stream Realignment 2
Malborough Hydraulic and Ecological Stream Realignment 3