I would like to include wetlands and riparian zones as hydrological response units (HRUs) within the agricultural catchment research unit (ACRU4) model. In the ACRU4 user manual there are graphical representations showing how one would typically conceptualize the riparian zone and wetland within the model. However, it is unclear as to how a user should specify that when stream/river bank full discharge is exceeded, water will spill onto the riparian zone or wetland. Please can someone specify how this is done?
1 Answer
All that you need to do is define the ChannelFlowCapacity (CAPM3S) variable. It can be difficult to know what value to use for this variable, however, for example, you could make an estimate of how often the wetland receives flood water from the channel and then look at the flow time series and determine the appropriate flow value for the variable.
Alternatively, you could set a very low value for the variable so that the wetland stays wet most of the time.