Density is the key factor in a new theory for finding groundwater.

Divining rods are out and science is in - for the National Centre for Groundwater Research and Training at least.

The centre’s director says researchers have been looking for new ways to monitor underground water supplies, focussing on the ways that density could affect the subterranean flow.

National Centre for Groundwater Research and Training director Craig Simmons says research seems promising so far, and has created enough confidence for further testing.

He says that by changing the density of the groundwater, either by adjusting its temperature or salinity, both the rate of flow and the direction of the groundwater can be affected.

He says in many cases, warmer or saltier water appears to change its flows underground.

Researchers say most groundwater flow is not driven solely by its density, but recent experiments suggest that density can have a significant impact.

Mr Simmons recently spoke to ABC radio about the latest findings; the full interview is accessible here.