Showing posts from July, 2008

EMC Washoff in SWMM5

There are four steps to using EMC concentrations in your network:

1. Define your pollutant by adding a pollutant using the Data=>Quality=>Pollutant command:

2. Define the Land Use by using the Data=>Land Uses command or the Land Use Editor:

3. Define Buildup to be None by clicking on the None Tab:

4. Define the EMC Washoff concentration by clicking on the Washoff Tab:

This is where you would add a GW concentration


Hurricane Dennis, Tampa 2005


Papaya Bugs and Gators

Papaya Bugs and Gators in the Backyard

A bug on our backyard Papaya trees. The papaya trees survived but the frost of January 2008 killed many of the trees. They are growing back, however.


PuddleBlog is the image history of one small to large puddle on an American Street:

What is Puddleblog, you ask? Puddleblog chronicles the epic journey of one puddle, bracing for an uncertain future.

It’s a blog. You know, for a puddle. Specifically, the puddle that graces the corner of Jay and Plymouth, a couple blocks east of the Manhattan Bridge. Maybe if this thing catches on we can think about including other qualified puddles.

Note now forwards to which forwards to one of the wonderfulNing social network sites.

SWMM 3,4 to 5 Converter Interface

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..

Hydrology in Ecclesiastes

Hydrology in Ecclesiastes

1:5 The sun also ariseth, and the sun goeth down, and hasteth to his place where he arose.

1:6 The wind goeth toward the south, and turneth about unto the north;
it whirleth about continually, and the wind returneth again according
to his circuits.

1:7 All the rivers run into the sea; yet the sea is not full; unto the
place from whence the rivers come, thither they return again.

Note: This was a better description than in Aristotle.

Hurricane Ivan in Pittsburgh, 2004

Pittsburgh International Airport recorded the highest 24-hour rainfall for Pittsburgh, recording 5.95 in. of rain. NWS Pittsburgh Climate Data, August, 2004." Hourly Climate Data. Pittsburgh, PA. 21 June 2006.

Spatial Step in SWMM 5

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 equationuses 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

SWMM 5 Tools

In the newest version of EPA SWMM (, 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 ( ... 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 "Paramete…

Global Rainfall