Quoted from: "Phu Nguyen et al., A high resolution coupled hydrologic–hydraulic model (HiResFlood-UCI) for flash flood modeling, Journal of Hydrology" https://doi.org/10.1016/j.jhydrol.2015.10.047
HiResFlood-UCI is a coupled model based on the heritage of HL-RDHM and BreZo. The coupled model uses HL-RDHM as a rainfall-runoff generator and replaces the routing scheme of HL-RDHM with the 2D hydraulic model (BreZo) for better simulating flash floods at river scale.
The coupled model is being implemented and tested for some flashy catchments before being applied for the whole CONUS and other parts of the world. In this loose coupling scheme, HL-RDHM and BreZo components are run in parallel. The framework is designed for processing the results from HL-RDHM to the form which BreZo can read as inputs. The whole coupling process follows the steps below and is illustrated in Fig 2.
1. Setting up HL-RDHM
2. Reprocessing runoffs
3. Procedure to design efficient mesh for BreZo
4. BreZo simulation and output processing
5. Model calibration

Fig. 2. HiResFlood-UCI coupling framework structure from initial input of rainfall and temperature through HL-RDHM rainfall-runoff generation to the final BreZo simulation output.