Abstract. Management of water resources requires understanding of the hydrology and
hydrogeology, as well as the policy and human drivers and their impacts. This
understanding requires relevant inputs from a wide range of disciplines,
which will vary depending on the specific case study. One approach to gain
understanding of the impact of climate and society on water resources is
through the use of an integrated modelling process that engages stakeholders
and experts in specifics of problem framing, co-design of the underpinning
conceptual model, and discussion of the ensuing results. In this study, we
have developed such an integrated modelling process for the Campaspe basin in
northern Victoria, Australia. The numerical model built has a number of
components:
Node/link based surface water hydrology module based on the IHACRES
rainfall-streamflow model Distributed groundwater model for the lower catchment (MODFLOW) Farm decision optimisation module (to determine irrigation requirements) Policy module (setting conditions on availability of water based on existing
rules) Ecology module (determining the impacts of available streamflow on platypus,
fish and river red gum trees)
The integrated model is component based and has been developed in Python,
with the MODFLOW and surface water hydrology model run in external programs,
controlled by the master program (in Python). The integrated model has been
calibrated using historical data, with the intention of exploring the impact
of various scenarios (future climate scenarios, different policy options,
water management options) on the water resources. The scenarios were selected
based on workshops with, and a social survey of, stakeholders in the basin
regarding what would be socially acceptable and physically plausible options
for changes in management. An example of such a change is the introduction of
a managed aquifer recharge system to capture dam overflows, and store at
least a portion of this in the aquifer, thereby increasing the groundwater
resource as well as reducing the impact of existing pumping levels.
Metamodel-assisted analysis of an integrated model composition: An example using linked surface water – groundwater models
