# ------ 3.4.10.1 Optimize Pipe Depth

Last Updated: 24 May 2022         For: OptiSurface Designer V3.5.4

This feature is under development and experimental. Use at your own risk.

Overview:  Calculates the optimal pipe depths for underground drainage pipe (often referred to us tile).

Displayed by:
Menu: Tools > Subsurface Drainage > Optimize Pipe Depth

Or Appearance: Calculate Using Topography: Select the Surface to carry the calculation on.

Zone Name:  Select the Zone Name to carry out the calculation on.

Zone Colour:  Change the color of the Zone shown in the Map.

Calculation Spacing (m or ft):  Defines how far apart the calculation points for the design surface are.

Join Tolerance (m or ft): If another pipe is found to be within this tolerance distance, then it will treated as being joined and during the depth optimization, they will be constrained at the same elevation so they can be connected in the real world.

Minimum Main Slope (%):  Minimum acceptable slope in %. Enter a positive slope for falling in the direction of the last point of the reference breakline. Typically 0.05% for minimum acceptable drainage. Note: You need to tick the tick box ‘ON’ to adjust the value and use this constraint in the calculations.

Maximum Main Slope (%):  Maximum acceptable slope in %. Enter a positive slope for falling in the direction of the last point of the reference breakline. Note: You need to tick the tick box ‘ON’ to adjust the value and use this constraint in the calculations.

Smoothing (m/% or ft/%):  Defines how rapidly the slopes can change. This effectively smooths the surface so the grade changes do not change too rapidly e.g. from minimum slope to maximum slope in a short distance. A typical value is 100 m/% (300ft/%) but depends on how much soil you want to shift versus how smooth you want the finished design. The grade changes are calculated at every grid point. For example, if the point spacing is set to 10m, and Smoothing Distance is set to 100 m/%, then at each grid point the slope can change a maximum of 0.1% (10/100). Eg from 0.1% to 0.2% at one grid point, then the next grid point it could go from 0.2% to 0.3%, etc Note: You need to tick the tick box ‘ON’ to adjust the value and use this constraint in the calculations.

Max Allowable Elevation (m or ft):  Defines the maximum elevation allowable for the subsurface pipe.

Min Allowable Elevation (m or ft):  Defines the minimum elevation allowable for the subsurface pipe.

Min Depth (m or ft):  Defines the minimum depth allowable for the subsurface pipe below the selected Topography surface.

Target Depth (m or ft):  Defines the ideal depth of the subsurface pipe the selected Topography surface.

Max Depth (m or ft):  Defines the maximum depth allowable for the subsurface pipe below the selected Topography surface.