https://doi.org/10.1016/j.jhydrol.2025.132821

Shook, Kevin R.; Pomeroy, John W. (2025) The hysteretic and gatekeeping depressions model − A new model for variable connected fractions of prairie basins, Journal of Hydrology, Vol. 654, 132821, https://doi.org/10.1016/j.jhydrol.2025.132821

The Prairie Pothole Region of western North America has unusual hydrology and hydrography. Its level, post-glacial topography means that many drainage basins are dominated by internally drained depressions, rather than having conventional dendritic drainage networks of stream channels. Modelling the hydrology of these regions is difficult because the relationship between depressional storage and the connected fraction of a basin is hysteretic. Existing models are either computationally intensive and require high-resolution Digital Elevation Model (DEM) data which may not exist or require calibration and cannot reproduce the hysteresis between the basin connected fraction and depressional storage. The Hysteretic and Gatekeeping Depressions Model (HGDM) has been developed to simplify modelling of prairie basins with variable connected/contributing fractions. The model uses “meta” depressions to model the hysteretic responses of small depressions and a discrete model of large depressions, which cause “gatekeeping”, meaning that they prevent upstream flows from reaching the outlet until the depressions are filled. The HGDM was added to the Cold Regions Hydrological Modelling (CRHM) platform which is one of the few models that has successfully simulated land surface hydrology in the Canadian Prairies. CRHM + HGDM is tested by modelling streamflows at Smith Creek, a basin in southeastern Saskatchewan, Canada. It is demonstrated that CRHM + HGDM can reproduce the relationship between the connected/contributing fractions of sub-basins and their depressional storage at least as well as existing models. Importantly, it appears that HGDM can be used with coarse-resolution DEMs, which may permit its use in the many locations where higher-resolution data is unavailable. The simplicity and limited parameterization needs of HGDM may allow for broader representation of depressions and variable contributing area in prairie hydrology.

Prairie Water

Keywords: Prairie; Pothole region; Modelling; Variable contributing area; Hysteresis

https://www.sciencedirect.com/science/article/pii/S0022169425001593