drainage tools toolbar, click the 
conduit properties button.
This option shows the properties of a drainage conduit and allows you to modify them.
On the drainage tools toolbar, click the conduit properties button.
You will be prompted to select a conduit from the drawing. As you move the mouse cursor the nearest conduit is highlighted. Click to select. The conduit properties window is shown.
The current soffit level and invert level are shown for the manhole at each end of the conduit. If you change the soffit level then the invert level will automatically update to reflect the conduit diameter. Similarly, if the invert level is changed then the soffit level will automatically update to maintain the conduit diameter.
Changing either the soffit level or invert level will affect the conduit gradient.
By default, the pipe colour is taken from the relevant layer, based on whether they are a surface or foul pipe as well as whether it is flagged as part of the private/plot drainage. Tick the Manual checkbox next to the colour box to instead have this pipe drawn using the colour shown in the colour box.
Clicking on the colour box will bring up a colour picker window. This allows you to select a bespoke colour for this pipe which will be shown in both the plan and longsection windows.
The pipe length shown is the 2D plan distance from manhole centre to manhole centre.
The pipe volume is calculated from the 3D pipe length between the two manhole's internal walls, taking into account whether each manhole is circular or rectangular. This gives the effective storage space of the pipe as the volume shown does not overlap with the manhole storage volume.
The pipe volume shown gets updated when the diameter or gradient of the pipe is changed.
By default a pipes pipe number is automatically generated so that they are correctly maintained for export to other drainage design systems like MicroDrainage. In the event that you need to change this default behaviour, changing this number changes the run number for this particular pipe from say 2.001 to 3.001. Note, this only changes the run number (the number before the decimal place) and not the pipe index (the number after the decimal place).
This value can only be modified when the outfall for the selected pipe's network has the Auto Run Numbering option turned off in the Manhole Properties window.
The current conduit diameter is shown. A drop-down list if standard conduit diameters is available, from which a different diameter may be selected.
If you want to specify a diameter which is not shown on the drop-down list, then select the Non-standard diameter option and enter the required diameter in the box.
If you change the conduit diameter then you'll be asked if you wish to the invert levels or the soffit levels to change to accommodate the change. The invert or soffit levels will then update accordingly.
Here you can specify a manual pipe material and bedding type.
Specify the contributing drainable area for surface water conduits here, or specify contributing units for foul conduits. If you are editing a surface water conduit, you can enter the impermeable percentage as well.
Specify the roughness factor for this conduit.
The current gradient of the conduit is shown. If you change the gradient then the invert and soffit levels at one of the manholes will update accordingly. You can select which of the two manholes will maintain its level and which will update to achieve the required conduit gradient.
If the conduit is shallow under the surface it may require concrete protection above it to prevent damage from potential ground movement. By default, shallower than 1.2m under the designed road surface requires concrete protection, but otherwise under the existing ground surface a depth of 0.9m is considered to require concrete protection.
The software will automatically detect any part of the conduit where the depth would require concrete protection, and this will be shown on long-section views and on the 3d View.
If required, you can set different depths for concrete protection for each conduit.
Note: The two depths are indicated on the preview image by a grey line (minimum depth under designed surface) and a green line (minimum depth under existing ground) drawn above the conduit. This is also how the depths are indicated on a longsection with Drainage Min Cover display set On. See Longsection View Properties for more information on how to toggle Section Display Items.