Northbank Tributaries

Various creeks and streams drain the Richmond Range and flow into the Wairau River on its northern bank, opposite Wairau Valley.

These include Cat Creek, Timms Creek, the Onamalutu River, Bartletts Creek, Top Valley Creek and Pine Valley Stream.

Associated with each of these surface waterways are shallow gravel groundwater systems known as riparian aquifers. Relatively little is known about their dynamics yet, but they rely on flow losses from streams. They are likely to drain quickly due to the steep grade of the gravels, and have limited storage.

The conceptual diagram below represents the latest understanding of these aquifers. Much more remains to be learned.

While each catchment has unique characteristics, generally stream flow is lost to the gravels forming the scree fans, re-emerging in the lower reaches where the gradient flattens near the Wairau River.

Surface and groundwater is used for a variety of purposes including drinking, stock supply and limited crop irrigation.