Investigation into Bega groundwater hydrology continued last week with drilling near the existing Bega borefield.

SMEC and subcontractor Adams Drilling are undertaking the drilling investigations for Bega Valley Shire Council.

Four monitoring bores and one test bore are being drilled to record lithological profiles, take sediment samples and for pump testing and water quality monitoring.

Council’s water resources coordinator, Ken McLeod, said the investigation will guide the location and depth of new bores for supplying drinking water to the Bega-Tathra area over the next 50 years.

“The existing Bega Borefield was built in the late 1970s and needs renewal,” Mr McLeod said.

“The investigation will also be used to develop and calibrate a groundwater model of the aquifer to simulate the impacts of drought and climate change on the amount and availability of water for users and the environment.

“Another aspect is to assess the concentration of iron and manganese in the groundwater at various depths to help select the optimum extraction level for drinking water and provide water quality data required for the design of the new Bega Water Treatment Plant,” Mr McLeod said.

The area for the investigation was chosen following the completion of geophysics stage late last year, which gathered data on subsurface features such as the depth to bedrock and areas of clay, sand and gravel and the geometry of the river valley around Bega.