Jeffrey Walker
Study Area: Murrumbidgee
Consider a layer of soil 2.5 m thick, with 50% porosity.  A change of 2% v/v in moisture content of this layer would produce a change in the gravitational acceleration at the surface of 1 G  (10 nm s-2), which is at the limit of resolution of present-day gravimeters.

Additional sites for the measurement of gravity, soil moisture and groundwater level will be installed across the Murrumbidgee at two distinct scales.  Seven additional sites will be installed to provide measurements approximately every 50 km in the east-west transect.  A further fifteen sites will be installed in the Kyeamba Ck sub-catchment to provide data on an approximate 3 km  3 km grid. (Total of 22 extra soil moisture sites)