The Murray Darling Basin Authority needs information about the distribution of inundation at certain flow levels to efficiently plan the delivery of environmental water.  One of the models the MDBA have used to assist their planning is the River Murray Floodplain Inundation Model, or RiM-FIM.  These models use satellite image observations and digital elevation data to predict the distribution of inundation through a local area at a given height of water at a nearby flow gauge.  These models are relatively cheap and fast to create compared to more complex models, and they have some characteristics that influence the range of conditions in which they can be best applied.  This presentation will describe the RiM-FIM method and some of the challenges that have been addressed in a range of areas in the MDB.