Layer States in Civil 3D
Jerry Bartels of Autodesk demonstrates the use of the AutoCAD LAYERSTATESAVE command to save and restore Layer properties in Civil 3D.
Jerry also covers the upgrade of older Express Tools Layer States that may occur in upgrading a drawing to 2018 if you employed those previously.
and the Civil Immersion blog.
Frankly, if you don't employ Layer States Civil 3D is pretty much unusable. You certainly work to hard.
Jerry, says the following over simplicification in his post lead in, "Using these layers, we control how (or if) various parts of our model are displayed."
Actually, Civil 3D Style and Reference tools do the bulk of the information management control in Civil 3D and not just AutoCAD Layers.
The AutoCAD LM command and Layer States allows Style representations to practically function for production work in Civil 3D.
The Framework for Civil 3D includes Layer Spreadsheet Tools that help you build and maintain the Layer system and Layer States.