The DREN-URBA’S 2.0 Drawing Tab

DREN-URBA, in its new version (2.0) includes a drawing window, on which it is now possible to directly create the components of the urban drainage system that you will calculate or design.

We started to incorporate this functionality into our software (those who require it, of course, the first one being the Water Demands Allocator) and, in the case of our stormwater drainage design software, tools we have previously created have improved, so as to offer the user ease when creating and analyzing such systems.

In this tutorial we introduce you the software’s DRAWING Tab, through a video in which we make the journey through each of its tools.

You will see that there are several features that allow you to simplify the system’s creation and, once you start with the drainage system design and analysis, these tools will visually keep you aware of changes in the hydraulic results of each of the urban drainage system components.


The Drawing tab presents options that allow you to import objects that are contained in drawing files with DXF or DWG AutoCAD’s format.

You can create, from the import, four types of objects to conform the stormwater urban drainage system in your project:

  • Elevation Point is a new feature that we have incorporated into this version and pretends to represent topographical references, —specifically, points of known ground elevation—that can be added to the drawing area of such form that they could be used to determine or to automatically assign the ground elevations of SOFTWARE objects, like streets or channels endpoints or manholes in the sewer system.

Thus, you will be able to convert the following graphic entities to Elevation Points in THE SOFTWARE:

Circles or points where the center’s Z coordinate has a nonzero value (as this will be the point´s elevation).

Single or Multiple Lines Texts. In this case, the software will take the X and Y coordinates of the text’s insertion point to set the X and Y position of the Elevation Point and the text’s string content will be assigned, if valid, as the ground Elevation of the Elevation Point created.


  • Manholes and Storm Sewer Pipes. Here, as in our other products, graphical entities, such as circles and points, are converted to Manholes; single and multiple texts are converted to Manhole´s labels; and lines or polylines to sewer pipes sections.
  • Sub basins. You can also create, from importing closed polylines in the drawing file, sub basins or tributary areas that can later be assigned to Streets and Manholes.

If the sewers network data, that is, manholes and pipe sections, as well as the elevation points, are contained in a Microsoft Excel file, it is also possible to import and convert them through this option in the Objects import panel.

The background image panel allows you to include a plan layout contained in an external drawing file, which will serve as the basis for creating the different components of your stormwater drainage system. You’ll find options to change its object´s layers display and color and, of course, you can also enable or disable their whole by displaying in the drawing area.

The Layers panel gives similar options, but now it handles the layers of the objects that make up your project.

The Edit panel includes buttons that allow you, for a previously selected object from the drawing area:

  • To Show Object’s properties dialog.
  • To Remove it from the Project.
  • To Change its current location in the drawing area by selecting the movement’s starting and end points.
  • To Show the objects’ quick selection dialog, with which you can include in the list of selected objects those that meet the condition you set here.
  • You can also easily search an object in the urban drainage system through this option, in which case the drawing area´s display will change, so as to zoom in the selected one; in addition, the object will be added to the current selected objects list.
  • Finally, to cancel any active command, you can use the Cancel button, thus moving to the object’s selection mode.

Regarding the objects selection mode, you must know that you can select the objects one by one by clicking on each of them.

But you can also make multiple selection by pressing the keyboard’s control key and selecting a rectangle in the drawing area with the mouse. Here you must click on the location of the first corner of the rectangle and, holding down the left button, go to the position of the diagonally opposite corner.

Any object that is inside the created rectangle will be selected.

Additionally, when you select any object in the drawing area and click the mouse’s right button, a floating menu appears with shortcuts to one or more of the previously described tools.

In the Tools panel, there are three new features that will make your job of creating and editing objects in the modeled urban drainage system much simpler.

The first one is the Global Editor, which allows you to modify specific properties in one or more objects of the same type that you have previously selected.

For example, when you select, from the drawing area, several pipe sections in the storm sewers network and click the button, you’ll see the dialog directly showing the properties that could be changed for these objects.

Also, you can access this dialog without having selected an object, in which case you can select objects by its name from this list and then specify the properties to modify.

Here, holding down the Control key, you can select rows that are not consecutive.

Then there are the buttons that let you create the aforementioned Elevation Points as well as assign their elevations to the urban stormwater drainage system’s components.

When you use the Elevation Points Creation button, you must only go to the drawing area and click on the point where you want the topographical reference to be created, then enter the respective elevation value so that it is created within the project.

Once you’ve created, or imported, as previously seen, the elevation points, you can use the Set Elevations button to assign or calculate the street’s endpoints and Manhole’s ground elevations.

THE SOFTWARE will try to perform the elevations calculation or allocation or, if needed, for each surface system and sewers network on the project, the software will show the street’s endpoints or manholes that failed in obtaining a ground elevation.

In this case, only in surface system 1 will points remain without elevation. We would have to go to each of them and make the introduction of this value manually, if it is necessary.

Bear in mind here that in the Settings tab, Calculation Parameters panel, general button, you have the options to define how the Elevations will be allocated:

  • Assigning to the street endpoint or manhole the Elevation of the closest Elevation point, provided it is within the range defined by the radius value you enter in this text box.
  • Or interpolating elevations of those Elevations Points that are within a certain radius, which corresponds to the value you specify here too.

Regarding this last option, you should keep in mind that the ideal interpolation condition is that each street endpoint or Manhole has at least two elevation points located in diagonally opposite quadrants, so as to ensure good results.

Finally, there are the options to display results in streets, channels, and pipes sections, using colors and values that you shall specify for your project.

So, you have a button that allows you to generate the color scale for each type of object and for each property range.

Double clicking on the color cell, you gain access to the color selection dialog, so you can set a new color to use for this range. Save your changes and close the dialog.

Then, select the property to be shown in the respective color scale for each object type and, finally, activate the display to see the changes in the drawing area.

This is a very useful tool when you’re performing the analysis and design of the urban drainage system of both the surface part, that is, the flow in streets and avenues and drainage inlets location, as well as the stormwater sewers part, as it lets you visualize changes as soon you change any values in your project´s objects.