Building the Urban Sanitary Sewer Networks in Your Project

In this video you will see how the GUI of CLOACAS, the sanitary sewer design software, allows you not only to create, by directly drawing in its drawing area, the sewer network’s components (sewer pipes and manholes), but will also allow you to import objects from drawing files in DWG or DXF format and convert them into those hydraulics objects, so as to considerably simplify the system’s creation, analysis, and design.


Related Tutorials:

In the previous video, the first one of this series of five, we created a new sanitary sewer project, and on it we have defined the default options such as units, among others.

We have also loaded a background image from a drawing file, to be used as a reference plan for the urban area on which the sanitary network will be created.

Then, it is time to create the sanitary sewer network’s geometry for this urban sector, and the first thing to do is create a new network, by clicking this button from the SEWER PIPES tab.

In the dialog, we must enter a unique name for the new network and, optionally, a description and the text that will serve as a prefix for labels of the manholes that will be created in the drawing area. There is also a field to change the manholes label counter.

Creating One or More Sanitary Sewer Networks

In the current version of our software, you can create one or more urban sanitary sewer networks, each having a single discharge point.

This option is useful in sanitary sewer projects of large urban areas where different discharge points, for the sub-networks that comprise it, are required.

So, if needed, you can click the Add Button to create a new  sanitary network again.

In addition, note that a button for you to delete the current or active sanitary sewer network is also available, eliminating all the objects that comprise it. The button to change its name, description, prefix, and manholes label counter is also located here.

When there are several sanitary sewer networks within the current project, for those non-active networks, you may hide their respective components in the drawing area by activating this option. This is so you do not get confused while conducting the network’s creation and design.

Importing Graphics Objects Contained in Drawing Files

One of the available options for creating sanitary sewer networks in our software is importing and converting objects such as circles, lines, and polylines contained in a drawing file into the hydraulic objects needed for the design.

If you have a drawing file in which objects representing manholes, sanitary sewers, and manhole labels are separated by layers, as we see here in the AUTOCAD program, you can perform the aforementioned importing from our sanitary sewer design software.

In the DRAWING tab’s Objects Import panel, you will find the option to import drawing files. Click the button to display the import objects from the DXF or DWG files dialog.

In this dialog, you must, first of all, select the drawing file containing the entities to be converted.

Then note that some options are enabled so you can select objects based on the layers that group them.

In this case, let’s activate the three boxes in the Manholes and Sewer Pipes group, and in the lists next to each option, select the corresponding layer.

Note that in the case of manholes and their labels, it is possible that respective objects—that is, circles and texts—are within the same layer, so there is no need to worry about separating them into layers.

Click OK to close the dialog and see the importing results in the drawing area.

The network of our example project is successfully created, and if it were the case that the circles representing the manholes in the drawing file have the Z coordinate property to nonzero, you will see in the manhole’s properties dialog that, as part of the conversion process, this value has been assigned as its ground or rim elevation.

Similarly, if you edit the properties of any of the sewer pipe sections, selecting it and pressing the right mouse button to access the properties option from the floating menu, you will see that properties that we previously defined as default, in the initial configuration of the project, such as the diameter and type of pipe, among others, have been assigned.

After the importing, you need to verify the flow direction through the arrows drawn in each pipe section of the sanitary sewer network created in the project.

In this case, it is necessary to change the direction of some of them.

For this, you have this button to swap pipe section’s extreme manholes at the SEWER PIPES tab.

When it is activated, the status bar prompts you to select, in the drawing area, the sewer pipe sections to be modified.

Let’s click on the pipe sections in order to convey the wastewater flow to the sewer network’s discharge point.

When finished, click the right mouse button or the escape key to cancel the command.

As we referred to at the beginning, each sanitary sewer network must have a unique point of discharge, so for this one we will define the A0 manhole as such. We select it and from the Properties dialog we will check the “Discharge Point” box. Click OK to see that the symbol changes to indicate the current condition.

Creation by Drawing the Objects

Of course it is also possible to create the sanitary sewer network’s components by drawing them directly into the software drawing window.

For this you have the options to add manholes and sewer pipes.

Thus, you can create isolated manholes in the drawing area.

To split an existing sewer pipe section by inserting into it a manhole, just click on the desired one in order to generate two new pipe sections from it.

Note that if the pipe section’s extreme manholes have assigned a ground elevation value, the software will interpolate from them in order to obtain the inserted manhole’s elevation value.

Then you have the option to add sewer pipe sections, while creating at the same time the respective extreme manholes.

In this case it is important that you consider the direction of drawing that you have specified in the project’s general settings; if you have defined the upstream direction, the first click you make corresponds to the section’s downstream manhole.

If the downstream direction is active, the first click will correspond to the upstream manhole.

Elevation Points Creation Options

A new object we have built into our sanitary sewer design software is the Elevation Point.

This point allows you to create ground elevation references within the sewer project area that can be used by the software to determine, by interpolation or allocation, the manholes’ ground (or rim) elevation.

Like other objects within the software, you can create the elevation points through importing graphic entities such as points, circles, or texts in a drawing file in AutoCAD DWG format.

In this case, you must go to the Objects Import dialog in the DRAWING tab and, after selecting the drawing file with the objects to import, activate the option in the Elevation Points group to select the corresponding layer.

You should also specify what type of graphic objects you are about to import:

  • Points, in which it is supposed the elevation or Z coordinate property has a non-zero value.
  • Circles, in which case the Z Coordinate property is expected to have a valid value so as to be used as the Elevation Point’s ground elevation.
  • Texts, where it will be assumed that its contents represent the elevation of the Elevation Point to create. In this case, the coordinates X and Y for the new point will correspond to the text’s insertion point.

When you click OK, the Elevation Points’ creation and drawing process starts, as you will see; they now appear in the drawing area.

Once created, each point can be edited so as to modify, if necessary, the corresponding elevation value.

The other way to create elevation points is by inserting them directly into the drawing area.

To do this, click this button and then click on the desired location in the drawing area.

You will see that a data dialog appears, in which you will enter the elevation of the created point.

Elevation Assignment, Available Methods

Once the elevation points in your sanitary sewer project have been created, it is then possible to automatically determine the manholes’ ground elevations.

To do this you have two options that can be selected from the project’s General Settings dialog, Drawing Area tab.

The first one consists in assigning the nearest Elevation Point’s elevation, provided it is within the range that you define in this box.

And the second option determines the manhole´s elevation from the interpolation of the closest Elevation Points’ elevations, equally, provided that they are within the range you specify here.

The latter option forces you to have, in order to obtain adequate results, more than two points around each manhole. Preferably, these are located in opposite quadrants.

Once you have selected the method for estimating the elevation, you will also have two options for performing the allocation:

  • By Manhole. In this case, you should go to its properties dialog and click this button. If errors or warnings are not detected, you will see that by closing this message, the elevation has been assigned.

If you want to enter the value manually, overriding the automatic assignment, you can activate this box and enter the corresponding value.

  • The other way is to assign elevations to all manholes within the sanitary sewer system project. Here, you must click this button on the DRAWING tab to perform the corresponding assignment or calculation.

At the end of the process, an informational message will be shown telling you, if applicable, the incidents detected so that you can make the necessary adjustments.

Creating Sub Networks

The last thing you must do to shape the urban sanitary networks to the design in your project, is the definition of each network’s sub networks.

The idea of this definition is, on one hand, separating the sewer pipes sections according to their order.

To say, primary and secondary sewer lines, for example.

On the other hand, the division into sub networks will be used for the automatic design of each sanitary sewer network as well as for the longitudinal profiles generation of the resulting design.

For example, in this sanitary sewer system, we have a main sewer line, the A0, which originates in the system’s discharge point and ends up in the A7-A8 pipe section, which, for these purposes, is called a “Starting Sewer Pipe.” This condition should be set, activating this box in the Sewer Pipes Editor.

This main sewer line receives secondary ones, such as the A3 sewer line, which starts in this manhole and ends at the A3.3 manhole. Also, this last pipe section is a starting Sewer Pipe so we set it on its properties dialog.

We’ll do the same now with every possible flow path within the sanitary sewer network.

Defining the starting sewer pipe sections, we can then proceed to create the corresponding sub networks.

To do this, we click this button on the SEWER PIPES tab.

To create a new sub network, let’s start with the main line, the A0.

From the list of available or unassigned sewer pipe sections, we will select and add to the list on the right, the sections that comprise this sub network, starting with its starting sewer pipe section which is, remember, the A-8, A-7.

Note that we now follow the route, section by section, from the most upstream point to the sub network’s discharge point.

We will do the same with the remaining sub networks in this project.

At the end, this sanitary sewer network project includes all these sub networks.

Now, the sanitary sewer system’s geometrical part is ready for the design.

We must now, as we shall see in the following video, define the wastewater design flows to be used in this sanitary sewer project.