Components of SWMM

SWMM 3,4 to 5 Converter Interface
The SWMM 3 and SWMM 4 converter can convert up to two files at one time to SWMM 5. Typically you would convert a Runoff and Transport file to SWMM 5 or a Runoff and Extran File to SWMM 5. If you have a combination of a SWMM 4 Runoff, Transport and Extran network then you will have to convert it in pieces and copy and past the two data sets together to make one SWMM 5 data set.

The x,y coordinate file is only necessary if you do not have existing x, y coordinates on the D1 line of the SWMM 4 Extran input data set.



You can use the command File=>Define Ini File to define the location of the ini file. The ini file will save your conversion project input data files and directories.



You can use the command File=>Define Your Text Editor to define the location of the text editor program. The ini file will save your conversion project editor name.



You can get a copy of the latest SWMM 3,4 to 5 Converter Here..

Google Sites is a recent addition to the Google family that allows you to set up a collaborative web site focused on one or more topics. In the words of Google:

"Meet Google Sites, the newest addition to the Google Apps product suite. It was designed to allow you to easily create a network of sites and share them with whomever you choose. Google Sites lets you pull together information from across Google Apps by embedding documents, spreadsheets, presentations, videos, and calendars in your sites. Of course, we also harness the power of Google search technology so your search results are always fast and relevant."

The Google Site SWMM2000+ has so far duplicate information copied from the SWMM Ning Sites and the SWMM5 Blogspot.

A four foot gator living in a Stormwater Outfall in Florida.

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Purpose: The purpose of this note is to explain a significant dynamic wave routing difference between EPA SWMM 5.0.013 and EPA SWMM 5.0.011 and before. A few people have detected a difference. The previous solution(s) would use only the midpoint area (Amid) and hydraulic radius (Rmid) in the dynamic wave solution. The new solution will use a slider or linear combination of the midpoint area (Amid) and hydraulic radius (Rmid) and the upstream cross sectional area (A1) and hydraulic radius (R1). The slider is based on the Froude number in the link. The change involves the A and R link spacing in the two dominant terms of the St. Venant Equation:


The new method is a linear combination or slider that weights the value of A and R in the St. Venant Equation based on the value of rho (), or



where, Rho () is a function of the Froude number. The effect of this addition is that as the Froude number increases from 0.5 to 1.0 and beyond the area and hydraulic radius used as the pivot point in the St. Venant equation moves from the midpoint of the link to the upstream end of the link. When the Froude number is above 1.0 the St. Venant and Normal Flow equation both use the same cross sectional area and hydraulic radius which makes for a more stable model.

Just for reference, the equation for Qnorm or the Manning's Equation flow is



The equations for the calculation of Rho () as a function of the Froude Number (Fr) are:



If ALL of the follow conditions are true Rho ()is calculated:

• the pipe is not full,
• h1 >= h2, and
• qLast > 0.

where,
h1 is the head at the upstream end of the link,
h2 is the head at the downstream end of the link and
qLast is the last flow value in the link.

If any of these conditions are true then rho = 1.0 and the value of A and R are the values Amid and Rmid, respectively.
The next graph shows the relationship between Rho and the Froude Number.



The value of Awtd and Rwtd move from the midpoint of the link to the upstream end of the link as the Froude number increases from 0.5 to 1.0.




Conclusion: This change should make the solution more stable because there is no longer an oscillation between the St. Venant Equation A and R and the Normal Flow Equation A and R.

In the newest version of EPA SWMM (5.0.1.11), there is a new feature of allowing for Add-ins and third-party tools. One such Add-in, the Microsoft Excel, can be very helpful for input data editing and model calibration.

1. To activate the Add-in
This process is detailed in pp. 141 of the EPA SWMM manual (http://www.epa.gov/ednnrmrl/models/swmm ... manual.pdf). Basically the user needs to go to "Tools->Program Preferences->Configure Tools" on SWMM main menu. Then in the pop-up "Tool Options" menu choose "Add." A "Tool Properties" window will pop-up, and the user can assign a name to the Excel Add-in for the "Name" field. For the "Program" field, the user needs to navigate to the location of the Excel executable file at "C:\Program Files\Microsoft Office\Office10\Excel.exe" (the file path may vary). Leave the "Working Directory" field as blank, and choose "INPFILE" macro for the "Parameters" field. Check both "Disable SWMM while executing" and "Update SWMM after closing."

After the above is set up, click OK and the Excel Add-in is registered in SWMM5. The Add-in tool is under the "Tools" menu. One important thing now is to go to "Tools->Program Preferences," and in the pop-up window check "Tab Delimited Project File."

2. Use the Excel Add-in
The SWMM5 input file by default is a tab-delimited .txt file. The user can view the file using Wordpad, but the editing is not very convenient, especially when it comes to calibration for a watershed with large number of subbasins. The Excel Add-in provides great relief for such operations.

Create a simple watershed model in SWMM, and then go to "Tools->Excel Editor (or whatever the user names the Add-in)." The input file for the watershed model is then displayed in tab-delimited format in Excel. In this environment, the user can edit the input data much easier (as compared to double-click each model component and key in the values in the Graphic User Interface). This becomes more apparent when the number of subbasins increases. When the editing is finished, close the Excel program, and then click "YES" or "OK" to all the pop-up windows. After that, the SWMM model interface pops back and the input parameters are updated.

So with this knowledge the model setup process can be much easier. In the initial model setup, the user may not bother to input any parameter values (i.e. subbasin area, width, slope, etc.). Instead, the model can be delineated and all components represented. Then the user can open the "Excel Editor" and copy/paste the model parameter values from another table of pre-created input parameter values (which is always the case). This process will totally by-pass the manually key-in of parameter values.

The second case of this feature applies is the model calibration. In a traditional way, suppose the user needs to change the value of depression storage for the impervious area. That means for a 30-subbasin watershed, the user needs to roam around the watershed and double-click 30 times to finish that single parameter change. Imagine if it takes five times to find the best value for that single parameter. With this feature, the user can open up the input file, set a depression storage value for the first subbasin, and then drag down for all the other 29 subbasins. Close Excel and go back to SWMM, and the updated model can be ran immediately.

Source: http://ceeforums.com/forum/viewtopic.php?f=26&t=256&p=582#p582

The SWMM 5 data input files are not backwards compatible with previous versions of SWMM - you cannot open a file created in v13 with a v11 GUI without getting messages about Options or features present in v13 but not present in v11. Not everyone looks at the C code but the new options are listed in the file enums.h with a version notation:

SKIP_STEADY_STATE, TEMPDIR, IGNORE_RAINFALL, //(5.0.010 - LR)
FORCE_MAIN_EQN, LINK_OFFSETS, //(5.0.012 - LR)

The good feature about this message is that it tells you what MAY be different between the two SWMM versions. For example, if you used Link Offsets in v13 then you will not have a valid model in SWMM 5.0.011. However, if you are not using a new option in SWMM 5.0.013 then you will have a valid backwards compatible SWMM 5.0.011 input data set.

Source: http://www.popcitymedia.com/timnews/raingarden0521.aspx

A charming little rain garden shines on Mt. Washington

A lovely little rain garden has showered a once blighted corner on Mt. Washington, a splash of green that its creators’ hope may become a catalyst for sprinkling similar projects around Pittsburgh.

Pittsburgh’s Burt Hill dreamed up the idea pro bono as a way to expand the firm’s professional knowledge and investigate emerging environmental technologies for urban water runoff, explains Evaine Sing, graduate landscape architect. The project has become a labor of love on a 2,000 square foot parklet on the corner of Shiloh Street and Virginia Avenue.

Mt. Washington Community Development Corp., URA Mainstreets Pittsburgh Fund and Pittsburgh Public Works have assisted along the way and $10,000, labor and material donations were contributed by community members and local businesses including Shemin Nurseries and KMA/Landscape Forms.

“We wanted a project of our own that would work as a test kitchen for other projects and be a living example for our clients,” explains Sing. “We choose this site across from the CDC because we saw the potential for educating passersby on these sustainable methods.”

The park was subdivided into small ecosystems and plants were selected for their ability to absorb water and pollutants during rainstorms. Bioretention beds and vegetated swales will allow the garden to drain within 2 days, helping to absorb and prevent storm water runoff, explains Sing.

Other touches will include lighting, a plaza space, benches, stepping stones made from the recycled pavers, an electrical outlet for future concerts and a mural that will be created by Cory Bonnet.

“We’d love to see this kind of space happen more often in Pittsburgh, like 10,000 Rain Gardens in Kansas City, which has had an amazing impact on water quality and flooding,” adds Sing. “We hope the idea will spread.”

Writer: Debra Smit
Source: Evaine Sing, Burt Hill; Greg Panza, MWCDC

Image courtesy Burt Hill

If you are new to this site or revisiting please visit Notes Home to see a roadmap to the Notes. SWMM 5 Input Files and Notes can be found in SWMM5. SWMM 4 Input Files and Notes can be found in SWMM4.

SWMM 5 Blog: Spatial Step

SWMM 3,4,5 uses a spatial step equal to the length of the link. Or, in terms of the 1D St. Venant Equation for the calculation of flow used in SWMM 5:







In which is the length of the conduit.



The program will calculate the cross sectional area, hydraulic radius top width and depth at the upstream, midpoint and downstream sections of the link. The link solution is pivoted on the midpoint cross sectional area in the dominant dynamic wave terms and

and the non-linear term in the dynamic wave equation uses the upstream and downstream link cross sectional areas. In the finite difference equation in SWMM 5 the pipe shown below would have one length but use the cross sectional information from the upstream, midpoint and downstream points of the link.



The bend in the pipe would be modeled using the "other" category of losses

This is my explanation of the comments on on the blog http://hhwq.blogspot.com about the CDM version of SWMM 5. It was purely a QA/QC testing program used in the code and data set migration of SWMM 4 to SWMM 5 during the years 2004 to 2007.

CDM version of SWMM5

4 comments:

Robert said...

This version is a QA/QC version of SWMM 5 that was used to more closely compare the SWMM 4 to SWMM 5 results using extra data variables.

April 19, 2008 8:35 PM

Robert said...

It should not be used for modeling. You should use the EPA SWMM Web site to download the latest EPA SWMM version:

http://www.epa.gov/ednnrmrl/models/swmm/index.htm

April 19, 2008 8:36 PM

1. 

1. Subcatchment Runoff
2. Subcatchment Washoff
3. Node Water Depth
4. Link Flow Rate
5. Node Water Quality
6. Node Lateral Inflow
7. Node Flooding
8. Groundwater Flow
9. Groundwater Elevation
10. Snow Pack Depth
11. Link Flow Depth
12. Link Flow Velocity

These are the Delphi 7 options that should be used to prevent the integer overflow problem from occurring when using the Zoom command. Overflow checking and any Debugging options seem to be the cause of the integer overflow problem.

How to Use the SWMM 4 Dos Enginengine

• SWMM Engine Name Name of the SWMM 4 DOS Engine
• SWMM Input File - SWMM 4 Input file
  
• SWMM Output File - SWMM 4 Text Output File (.OUT Extension)
• Alternative SWMM Output File - Reduced SWMM 4 Output File (.RPT Extension)

How to Use the SWMM 5 Dos Engineine

• SWMM Engine Name Name of the SWMM 5 DOS Engine (usually called SWMM5.EXE)
  
• SWMM Input File - SWMM 5 Input file
  
• SWMM Output File - SWMM 5 Output Binary Graphics File (.OUT Extension)
  
• Alternative SWMM Output File - SWMM 5 Output Text File (.RPT Extension)