SWMM5, InfoSWMM

Subject:  SWMM 5 Fixed Surface Water Depth Boundary Condition

A large difference between SWMM 5 and SWMM 4 is how the Groundwater Aquifer interacts with the drainage network.  In SWMM 4 since the hydrology was simulated in the Runoff Block, the results saved to an interface file and the hydraulics were simulated in the Extran Block it was not possible to have a time step to time step interaction between the Aquifer and the Open Channels.  SWMM 5 has integrated hydrology and hydraulics so it is possible to use either a Fixed Surface Water Depth for each Subcatchment or the Receiving Nodes Node Depth Invert Elevation – the Aquifer Bottom Elevation.  The groundwater thus flows either to a fixed boundary condition as in SWMM 4 or to a time varying boundary condition.

Subject:  SWMM 5 Threshold Groundwater Elevation

A large difference between SWMM 5 and SWMM 4 is how the Groundwater Aquifer interacts with the drainage network.  In SWMM 4 since the hydrology was simulated in the Runoff Block, the results saved to an interface file and the hydraulics were simulated in the Extran Block it was not possible to have a time step to time step interaction between the Aquifer and the Open Channels.  SWMM 5 has integrated hydrology and hydraulics so it is possible to use either a fixed Threshold Groundwater Elevation for each Subcatchment or the Receiving Nodes Invert Elevation.

Subject:   Aquifers in SWMM 5

 Groundwater in SWMM 5 is modeled as two zones: (1) Saturated and (2) Unstaturated.  The data for the Groundwater Simulation consists of physical data in an Aquifer and elevation and flow coefficient and exponent data in the Groundwater Data.  The Aquifer data object can be applied to multiple Subcatchments but each Subcatchment has its own set of Groundwater data.  For example, in this model all of the Subcatchments share the same Aquifer data but each Subcatchment has different elevation and flow data – the labels on the basin are the groundwater elevations.

Subject:  InfoSWMM and Arc GIS Layer Properties for Surcharge and Flooded Time

 An important advantage of using InfoSWMM is the ability to use all of the Arc GIS layer and programming tools.  For example, you can graph the model results for the flooded and surcharged time in a node using a Bar/Column plot to show the surcharge time in the node and the flooded time in the node.  A flooded node is always considered to be surcharged but a surcharged node does not always flood.  The surcharge level is any water surface elevation above the highest connecting crown elevation but the flooded time is a water surface elevation at or exceeded the rim elevation of the node.

Subject: InfoSWMM and Arc GIS for Create Graphs Using Network Data and Model Results

An important advantage of using InfoSWMM is the ability to use all of the Arc GIS layer and programming tools.  For example, you can graph the model results in Bar,  Pie, Scatter, Bubble or other types of Graphs once the model data and model result layers are Joined together.  The image below shows a thematic mapping for Node Flooding, Conduit Force Main Type and a Pie and Bar Chart of Node Flooding Time and the Q Full in the links, respectively.