Modelling Wairau River-groundwater exchange fluxes

Abstract

The Wairau Aquifer is almost exclusively recharged by surface water from the Wairau River and serves as the major drinking water resource for Blenheim and the surrounding settlements on the Wairau Plain. The aquifer has been identified as the Wairau Plain’s key natural resource by the Marlborough District Council (MDC) and until now has been perceived as an endless source of water. However, currently no new allocations of Wairau Aquifer water are being consented because the safe yield limit has been reached. There is also a small but declining trend in aquifer levels in the Conders area which needs to be accounted for. Therefore, it has been made a high priority by the MDC to better understand the limits and the mechanics of the recharge mechanism.