Inflow and Level Events
Inflow and level events define inflow and level hydrographs for inputs to the network during a simulation.
These events can be viewed and edited on the Event Editor.
Each column on the Event Editor grid represents a single inflow hydrograph or level hydrograph, and the object at which that hydrograph is applied is shown in the column header.
Inflow and Level events cannot be used in simulations in conjunction with Time Series Database objects.
Sub-Events and Profiles
Inflow and Level events, like many other types of event, are divided into:
- sub-events - a time period during which input to the system takes place
- profiles - describing the input at a single object
For more details on how InfoWorks ICM deals with sub-events and profiles, see the main Events topic.
Inflow Hydrographs
In InfoWorks networks, Inflow hydrographs may be applied to:
- Nodes - inflow is applied at the referenced node. If the referenced node is an outfall, inflow will be ignored.
- Links - inflow is applied laterally to the link. If the object referenced is a control, the inflow will be assigned to the upstream node of the control, unless that node is an outfall, in which case the inflow will be ignored. If the object referenced is a bridge link, inflow is applied laterally to the contraction reach.
- 2D Point Sources
- 2D Line Sources
- 2D Boundaries
In SWMM networks, Inflow hydrographs may be applied to:
- Nodes - inflow is applied at the referenced node. If the referenced node is an outfall, inflow will be ignored.
- 2D Boundaries
If an inflow hydrograph is applied to an Outfall node the hydrograph will be ignored during simulation.
Level Hydrographs
Level hydrographs can only be applied at an outfall node.
The level hydrograph is used to represent changes in seawater or river level that cause backflow into the network.
If a level hydrograph is applied to any type of node other than an Outfall, it will be ignored during simulation.
When carrying out 2D modelling in InfoWorks networks or SWMM networks, level hydrographs may also be applied to 2D Boundary objects.
Network Datum
When setting values for level, all values should be relative to the same datum level. A national datum level may be used (in the UK this is called Ordnance Datum and values are described as above Ordnance Datum (AOD)). You could also choose your own datum, and many users choose the invert level of the lowest conduit in the network.
When using level hydrographs, be careful when choosing the datum level. If the datum level used is above the level of some or all of the network, the level hydrograph may contain negative values. In this case a potentially large increase in level will occur if the default value of zero is used.