CAS-HYDRO is a dynamic, distributed, object orientated, process based, hydrological model operating at the landscape scale. There are two facets to the design philosophy of the model. Firstly, the model should use a minimal parameter set. These parameters should be obtainable for any catchment in the UK from published national datasets. Secondly, what happens where and when within the catchment is important for understanding hydrogical system behaviour. Therefore, the model uses a fully distributed spatial structure and a continuous temporal representation.

Brief Overview:

CAS-HYDRO is an intergrated catchment simulation model. It simulates catchment hydrology, river channel flow, biogeochemical cycling and the human impact on natural system.


  • Simulation of terrestrial hydrological processes
  • Simulation of river flow processes
  • Simulation of nitrogen cycling
  • Simulation of the in-stream oxygen balance

Model Development

CAS-HYDRO was developed by Cascade Consulting, Leeds University and Durham University under a project funded by UK Water Industry Research Ltd.

The aim of the model development was to consider the impacts of climate change on water quality in UK rivers. This research question required a model capable of simulating the climate change impacts on both the terrestrial hydrology and biogeochemical cycling. The changes in these terrestrial processes would then drive the changes in the river channel network.

Picture of Broadway Foot Weir
Picture of a meadow