Increasing pressure is being imposed on Perth’s water supply due to population growth and a drying climate. In order to ensure long-term water supply for the city, the Water Corporation has introduced a Groundwater Replenishment (GWR) Scheme (Water Corporation, 2019). The Perth GWR scheme is in its’ second stage and is currently being expanded to enable a 28 billion litre recharge capacity into the Leederville and Yarragadee aquifers. GWR involves injecting treated wastewater into confined aquifers for storage to supplement traditional groundwater supplies.
Considerable analysis at the injection sites has been undertaken to improve well management and performance during drilling, injection and clean-up operations as part of the GWR project. Wireline logging technologies have been used to provide hydrogeological characterisation of the aquifers. Of particular interest is borehole magnetic resonance (BMR) which provides accurate measurement of reservoir porosity and an estimate of well permeability using well-known empirical correlations (Kleinberg, 2001, Neville and Hopper, 2017). The BMR estimated permeability can be translated into hydraulic conductivity and hydraulic transmissivity measurements. The permeability model typically used for sandstone reservoirs is the Timur-Coates model (Timur, 1968, Coates et al. 1991). This model requires calibration to local well information such that the model parameters correctly reflect the local geology. This is typically achieved by core analysis of plugs obtained from the well-sites of interest.
GWR project included flow-logging measurements at the injection sites to measure well transmissivity. We provide an alternative method of calibrating the Timur-Coates parameters using the transmissivity determined from flow logging tests across multiple wells (Dlubac et al. 2013). The measured Timur-Coates parameters and resultant transmissivities are compared to results obtained from the standard core calibration method. The proposed method allows permeability to be more accurately captured at the well-scale. Permeability measurements via BMR can then be used at other small monitoring bores for aquifer management.