Contour-Guided Terracing

What this mode is for

Contour-Guided Terracing is a variant of Terracing for laying out a new terrace along the lay of the land. Instead of guessing where the channel should run, you let the app draw the field's contour lines, pick the contour your terrace should roughly follow, and the app paints a shaded Terrace Zone — a corridor around that contour — for you to survey the channel and berm inside.

The key idea: the contour is a layout corridor, not a line to steer exactly onto. A true contour is dead level, but a terrace channel needs some fall to drain to an outlet. So you survey the channel within the zone, starting near the uphill edge and easing downhill toward the outlet to build that fall by hand. Then you survey the berm on the downhill side of the channel. After that, the regular Terrace design does all the math — channel grade, berm volume, soil balance — exactly as standard Terracing. The contour and zone are just there to lay the terrace out sensibly on the ground.

Use Contour-Guided Terracing when:

• You're laying out a brand-new terrace and want it to follow the field's natural contour.
• You have (or can collect) a surface map of the whole field.
• You want a visible corridor to keep the channel and berm in the right place as you survey.

You need a field surface first. Just like Contour Tiling, contour lines come from an elevation surface that covers the field. Contour-Guided Terracing uses the same DEM-source choices as Levee: survey a field, load a saved survey, load a saved LiDAR DEM, import a point file, or import a GeoTIFF DEM. If you do not already have LiDAR on disk, use LiDAR & Mapping while online to fetch and save the DEM first, then reconnect to the controller and choose Saved LiDAR DEM.

Workflow at a glance:

1. Connect to the controller.
2. Tap the Terracing card, then choose Contour-Guided Terracing.
3. Get a field surface — load a saved LiDAR DEM, saved survey, point file, GeoTIFF, or survey the field.
4. Set the Terrace Zone Width (default 12 m / ~40 ft, editable).
5. The app draws the contours, highlights the nearest, and paints the Terrace Zone band around it.
6. Survey the channel inside the zone — drift downhill toward your outlet to build fall, watching the zone-position readout.
7. Survey the berm on the downhill side.
8. Open the Terrace design dialog — channel grade, berm analysis, Auto Balance, all as standard Terracing.
9. Calibrate the BM, then grade the channel and the berm, switching with the Channel/Berm toggle.

In this chapter

• Before you start
• Quick start
• The Terrace Zone
• Surveying channel and berm
• Designing the terrace
• Grading the terrace
• Tips & gotchas
• Troubleshooting