Estimation of water and salt generation from unregulated upland catchments

Water and salt export to rivers is of particular importance in large catchments, such as Australia’s Murray-Darling Basin, where there are multiple users of the water resource. Comparing estimates of water and salt generated from upland catchments across large areas is difficult due to the lack of a comparable, consistent approach. River routing models are currently used to model water and salt movement along regulated reaches. However methods are still required to predict the individual contributions of water and salt from unregulated upland catchments to feed into these river routing models. The 2CSalt model has been developed to predict monthly water and salt export from these upland catchments. 2CSalt makes use of existing regional data sets such as topography (digital elevation models) and hydrogeology/salinity (Groundwater Flow Systems). 2CSalt was developed using the “TIME” modelling framework which allowed for a rapid development cycle through the reuse of existing and tested components. The results from current applications of the model show a strong match with measured data.