Showing posts from September, 2011

Reading the Output of Older SWMM 5 versions in Newer SWMM 5 Versions

Subject:   Reading the Output of Older SWMM 5 versions in Newer SWMM 5 Versions

It is very easy to read the output graphs and output text file from older versions of SWMM 5 in newer versions of SWMM 5 as long as the rules are followed:

1.You need to have the RPT file for the InputFileName or InputFileName.RPT
2.You need to have the OUT file for the InputFileName or InputFileName.OUT
3.The File Size for InputFileName.RPT is greater than 0
4.The Run Status for InputFileName.OUT is true based on the tests in CheckRunStatus
a.    // Starting from end of file, read byte offsets of file's sections b.    // Read # time periods, error code & file signature c.    // Read file signature & version number from start of file d.    // Check if run was completed e.    // Check if results were saved for 1 or more time periods f.    // Check if correct version was used g.    // Check if error messages were generated
Figure 1.   The RPT File or OUT File is not saved unless you 1st save the Current Simu…

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 an outfall node.  The culvert code and the shape of the culvert determine which FHWA equation is used to determine the flow INTO the Culvert during the simulation:
1.The flow from the St Venant Equation or
2.The flow from the FHWA equation
The minimum flow is used by the program. 

all_culverts.inpDownload this file

All Possible Culverts Example Model in SWMM5by dickinsonreNote:  Attached is an exampleSWMM5model that has all 57 culvert types possible in SWMM5 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 th…

How Dry Weather Flow is Used in InfoSWMM at a Node

Note:   How Dry Weather Flow is Used in InfoSWMM at a Node

How Dry Weather Flow is Used in InfoSWMM at a Nodeby dickinsonreNote:   How DryWeatherFlowis Used in InfoSWMM at a Node There are four components to the DryWeatherFlow (DWF) in InfoSWMM: 1.       The mean flow in user units at the node, 2.      The DWF Allocation Code – if you are using the DWF Allocator 3.      The Pattern for Weekday, Weekend etc for the mean flow. The data is entered or entered for you in the Node Inflow Icon or the Operations Tab of the Attribute Browser Node Inflow Icon and Associated Data Operation Tab Patterns You can also make global changes to your DWF using the Node DWF DB Table Under Extended Element Modeling Data via Blogger

SWMM5 Weir Rules, Head Calculations and Weir HGL Plots

Note:  SWMM5 Weir Rules and Head Calculations
This note attempts to explain both how the head upstream and the head downstream of a weir in SWMM 5 is calculated compared to the weir crest elevation and also to explain how the weir is presented in the HGL plot of SWMm 5.  There has been confusion in the past concering how the weir is shown compared to the actual weir calculations.  The node head is calculated obviously at both ends of the weir but the head over the weir is always based on H1-Crest or H2-Crest (Figure 1) and hence the weir should look flat – to the weir the downstream head is important but NOT the downstream node invert so the weir really is flat and should look flat in the HGL Profile across the weir (Figure 2).    The crest elevation is always relative to the upstream node invert elevation NOT the downstream node invert elevaation

Figure 1.  How the Head across a Weir is calculated in SWMM 5

Figure 2.   HGL Profile across a Weir in SWMM 5.0.022.  The black line should be…

Time Step Approximation based on Link Lengths

Note:  A rough approximation of the time step you need for an InfoSWMM or H2OMAP SWMM model can be found by finding the mean link length using the field statistics tool for the length in the Conduit DB Table and then estimating the time step from the mean length, mean full depth velocity and mean full depth wave celerity.
The time step actually used during the simulation is related to this velocity and the safety adjustment factor.  The larger the safety adjustment factor the larger the mean time step listed in the Routing Time Step Suggestion.

Stream Names in the USA

Stream Names in the USA from
Generic place names (or toponyms) such as Cumberland Gap or Mount Rainier provide general categorical descriptions of a geographic feature, in contrast to specific toponyms, which provide a unique identifier: Lake Huron. This map taps into the place names contained in the USGS National Hydrography Dataset to show how the generic names of streams vary across the lower 48. Creeksand rivers are symbolized in gray due to their ubiquity (although the etymology behind the American use of creek is interesting), while bright colors symbolize other popular toponyms. Lite-Brite aesthetic notwithstanding, I like this map because it illustrates the range of cultural and environmental factors that affect how we label and interact with the world. Lime green bayous follow historical French settlement patterns along the Gulf Coast and up Louisiana streams. The distribution of the Dutch-derived term kill (dar…