Murray Close

Principal scientist

Murray Close

Principal scientist Murray Close is a member of ESR’s Water, Waste and Social Systems Group. With over 36 years’ experience in groundwater research, Murray is an expert in groundwater conditions and processes in New Zealand.

Murray has served as programme leader on a number of major research programmes. Currently he leads the Groundwater Assimilative Capacity programme. The aim of this six-year government-funded programme is to assess to what levels contaminants and toxins that enter the groundwater system are naturally reduced. The research will assist in the management of water resources in New Zealand.

Past research has ranged from developing a method for predicting reduced groundwater zones, to developing tools for testing water quality, to working on an international project looking at measuring denitrification rates in groundwater, to developing a new method to study the structure of alluvial gravel aquifers.

“Most of the research I am involved in has practical applications for local government, industry and communities,” Murray says.

“Regional councils have the responsibility to implement the government’s freshwater reforms which seeks to balance the goals of ‘maintaining or enhancing water quality’ and ‘increasing production from agriculture’. Knowledge of the assimilative capacity of the groundwater system is crucial to estimating loads of contaminants entering into river and lakes.”

Since 1990, Murray has also coordinated New Zealand’s four-yearly national survey of pesticides in groundwater. The majority of wells sampled in each national survey have detected no pesticides and the concentrations of pesticides detected are mostly very low.

“It is important for us to develop an understanding of the whole subsurface system so that we predict what will happen as contaminants leave the soil layer, where they are transported, and what processes will affect them.  As part of this, we are working on ways to measure and model land-use impacts on groundwater quality,” he says.