Farm Dams Observation Point node is often used in the Source model with the node including but not limited to the farm dam node.
The functionality of the Farm Dams Observation Point (FDOP) node now can be accessed from CORE without the ObservationPointNodeModel plugin.
Similar to the farm dam node, the Observation Point Node can be created by dragging the FDOP icon 
from Node Palette or changing an existing node to the node type of FDOP.
Right-clicking on a node of FDOP can open the Editor to configure this node (Figure 1).
The inflows into a Farm Dams Observation Point (FDOP) come from two alternative Sources: (i) overflows from the upstream dam(s)/FDOP node(s)/subcatchment(s). (ii) local inflow generated by the interstation area between the upstream dam(s)/FDOP node(s)/subcatchment(s) and this observation point. These interstation inflows are calculated on the basis of reference timeseries (i.e. at a gauge) that has been scaled down/up. This scaling should reflect (a) the interstation catchment area relative to the reference catchment area and (b) the non-linearity of the relationship between the catchment area and flow, represented by the factor Z. For more information, please refer to the STED manual from SKM.
The parameters include the Scaling factorand Reference Timeseries in Value, Data Source, and Function Editor format. The user can select the option Value for the constant value, or Data Source for a timeseries defined in Data Sources, or define it by a function.
The inflow from an FDOP node and its upstream flow will be added together to the network.
Figure 1 Farm Dams Observation Point editor