As previously stated in Rivers - SRG, Source uses a link-node structure to represent river systems for modelling. In links, lag time and storage routing concepts are used for routing. Water quantity processes modelled comprise flow routing in links and a large range of processes modelled at nodes.
Two flow routing methods are available to model travel time and attenuation in links: pure lag or translation, and a generalised streamflow storage routing method, which can represent linear, non-linear, and variable parameter Muskingum routing (details on all these are available in Link storage routing - SRG). In the routing algorithm, river water (in-bank flow) fills the dead storage in a reach first before propagating through the reach. Overbank flow is considered for modelling interactions between surface water and groundwater. The surface water-groundwater (SW-GW) interaction component in Source (see Groundwater interaction module (Link storage routing) Analytical Tool - SRG for details) is integrated into the river network through links. (Extracted from Welsh, et al, 2013, with adaptations to suit the needs of the SRG.)
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