Category: Venant

Updated – Innovyze St Venant Solutions for InfoSWMM, InfoSewer, H2OMap SWMM and InfoWorks ICM and InfoWorks ICM SE

The assumptions behind Lumped and Distributed Models along with the assumptions of the St Venant Equations. InfoSWMMH2OMap SWMM, InfoSWMM, H2OMap SWMM, SWMM5, ICM and ICM SE are all Distributed models for Unsteady flow. InfoSWMM and InfoSWMMH2OMap SWMM have options for direct steady flow. ICM and InfoSWMM can also use a quasi steady flow solution. All of these Innovyze models use the Continuity Equation and Momentum equation for routing flows in links.

Runoff from One Watershed for a 100 Year Simulation with SWMM 5 Statistics for Peak, Mean and Total Runoff

Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download at to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM […]

The Non Linear Term in the Saint Venant Equation of SWMM 5

Subject: Non Linear Term in the Saint Venant Equation of SWMM 5 The flow equation has six components that have to be in balance at each time step: 1. The unsteady flow term or dQ/dt 2. The friction loss term (normally based on Manning's equation except for full force mains), 3. The bed slope term or dz/dx […]

How is the St Venant Equation Solved for in the Dynamic Wave Solution of SWMM 5?

Subject:   How is the St Venant Equation Solved for in the Dynamic Wave Solution of SWMM 5?   An explanation of the four St. Venant Terms in SWMM 5 and how they change for Gravity Mains and Force Mains. The HGL is the water surface elevation in the upstream and […]

How to Search These Blogs for Information about SWMM5, InfoSWMM or InfoSewer

Note:  How to Search These Blogs for Information   In each of the blogs search  for a term or a set of terms using the search button.   For example, here is with a search for venant     An equivalent Search in       An equivalent Search in     An […]

All Possible Culverts Example Model in SWMM5

Note:  Attached is an example SWMM 5 model that has all 57 culvert types possible in SWMM 5 in one model.  The culverts are 57 small individual networks consisting of an inflow node, an upstream open channel, upstream node for the culvert, culvert link with culvert code, downstream node of the culvert, downstream open channel and finally […]

Link Simulated Parameters used in either the Normal Flow or St Venant Equation of SWMM 5

Subject:  Link Simulated Parameters used in either the Normal Flow or St Venant Equation of SWMM 5   St. Venant equation – this is the link attribute data used when the St. Venant Equation is used in SWMM 5.  Simulated Parameters from the upstream, midpoint and downstream sections of the link are used. Normal Flow Equation – this is the link attribute data used when the Normal Flow Equation is used in SWMM 5. Only simulated parameters from the upstream end of the link areused if the normal flow equation is used for the time step. […]

Hysteresis Effect in the Link Flow versus Depth Relationship in SWMM 5

Subject:  Hysteresis Effect in the Link Flow versus Depth Relationship in SWMM 5 You can often get a hysteresis effect for the Flow versus Depth relationship in SWMM 5 due to the five component St. Venant equation used to simulate the flows ( .  A hysteresis effect is having two or more flow values for the same depth value in the link. […]