The concept of link-node can be extended to include devices which divert stormwater out of a combined sewer system or relieve the storm load on interceptors. In EXTRAN, all diversions are assumed to take place at a node and are handled as inter-nodal transfers. Diversion devices modeled by EXTRAN include: Weirs (both side-flow and transverse), orifices, pumps, and outfalls. These are discussed in the paragraphs below.