Stormwater Management Model (SWMM) Information for watershed water quality, hydrology and hydraulics modelers (Note this Blog is not associated with the EPA). You will find Blog Posts and Twitter Embeds on the Subjects of SWMM5, InfoSWMM, InfoSewer, SWMMLive, InfoSWMM SUSTAIN, SWMM4 and SWMM in general.
Starting from the bottom of the manhole you have these regions of computational interest:
1. Manhole Invert to the lowest link invert – the node continuity equation is used with the area of the manhole being the default surface area of a manhole,
2. Lowest Link Invert to the Highest Link Crown Elevation – the node continuity equation is used with surface of the node being normally half of the surface area of the incoming and outgoing links,
3. Highest Manhole Pipe Crown Elevation to Manhole Rim Elevation – the node surcharge algorithm in which the surface area of the manhole is not used and the surcharge depth is iterated until the inflow and the outflows of the node are in balance,
4. The region above the Manhole Rim Elevation which can use one of four options to calculate the depth and/or flow out of or into the manhole:
1. No Surcharge Depth is entered and No Ponding area is used – the excess water into the manhole is lost to the network and shows up as internal outflow in the continuity tables,
2. A Ponding Area is used and the excess flow will pond on the surface of the manhole and later go back down into the conveyance pipes.
3. A Surcharge Depth is used and the depth will continue to be calculated using the node surcharge algorithm in which the surface area of the manhole is not used and the surcharge depth is iterated until the inflow and the outflows of the node are in balance,
4. A Dual Drainage system is simulated and the excess flow of the manhole is simulated in the street gutters or the actual street,
5. You use a 1D/2D linkage between the 1D manhole and 1D links to a 2D Mesh and simulate the flow out and the flow into the manhole using a bottom outlet orifice that switches automatically between weir and orifice flow based on the depth on top of the manhole.
Soffit Level (pipe technology)The top point of the inside open section of a pipe or box conduit. The soffit is the highest point of the internal surface of a pipe or culvert at any cross-section. The soffit is also referred to as the pipe obvert. So it is not quite the Crown of the Pipe. Here is an image I found that hopefully explains it better.
Engine Error NumberDescription ERROR 101: memory allocation error. ERROR 103: cannot solve KW equations for Link ERROR 105: cannot open ODE solver. ERROR 107: cannot compute a valid time step. ERROR 108: ambiguous outlet ID name for Subcatchment
New InfoSWMM linked 2D Link and 3D Node graphics help you understand one of the most critical outputs in any Stormwater, Combined Sewershed or Sanitary Sewershed Network Model the value and timing of how full the pipes and nodes are over time and how this changes during Wet Weather Flow (Runoff or Infiltration Inflow).These new graphs are included in InfoSWMM v 14.6 and InfoSWMM SA V2 (InfoSWMM SA is not an Esri Extension in ArcMap but uses Arc Engine for GIS processing power) has many new graphical and map display tools that help answer the following modeling questions in a easy to understand group of linked Time Track Graph, 2D Graphs and 2D Thumbnails. If you are modeling a Stormwater Network and need to know the d/D or depth over maximum depth over time and at the peak of the Runoff event you can view linked graphs as shown in Figure 1.If you are modeling a Sanitary Network and need to find the d/D for Rainfall Induced Infiltration and Inflow (RDII) you can see the RDII fl…