This study uses a dynamic multi‐regional Computable General Equilibrium model of the Australian economy to examine the impacts of developing irrigated agriculture in remote North West Queensland. A potential investment and operational scenario is implemented using three alternative forecast baselines. In the first run using a business‐as‐usual baseline, there is a welfare loss from irrigation development, even with an optimistic shift in farm productivity and factor endowments in North West Queensland. In the second run, baseline demand for Australia's exports is assumed to grow at a faster rate and there is a small welfare gain. Simulating climate change impacts on crop yields, the forecast baseline of the third run includes a gradual reduction in farmland productivity in southern Australia. The simulations show the impacts of both supply and demand shifts on the welfare outcome, but on balance, clear welfare gains do not arise from the potential irrigation development.