An objective of the Commonwealth Environmental Water Office’s Long-Term Intervention Monitoring Project is to develop models that link fish population dynamics to flow events and regimes. In this talk I will explain why this objective was deemed necessary, highlight the risks, and explain how we’re managing those risks. Within LTIM the models will be used to project long-term population response to multi-year flow scenarios; project population response in areas where flows are delivered, but where fish data are not being collected; lift evaluation of flow response beyond that of the individual process (e.g. spawning); characterise uncertainty; and facilitate intervention analysis. While the approach we’re taking follows best practice in adaptive management, it is untested within the Murray-Darling Basin and so may therefore be considered risky by stakeholders. LTIM has managed this risk by investing in a diverse fish monitoring portfolio and undertaking precision analysis to determine methods are fit for purpose. I will present some results of those precision analyses demonstrating how the LTIM methods have greatly improved our ability to estimate population structure.