Maril's paintings and drawings for the Bureau of Reclamation show this tendency to reduction and composition. His ink drawings use the minimum number of lines to define a contour or figure. A sense of space is conveyed with the least information. It is not always easy to identify an individual mark as descriptive of a particular feature, but somehow the marks together describe a scene. The paintings are similar to the drawings in terms of simplicity, but instead of lines, Maril uses color fields.
Depth is indicated through atmospheric perspective and layering.
In Blanco Diversion Dam , the intense brown and red on the right middle mountain makes it feel closer to the viewer than the mountains above it, in the painting, appear to be further back in the distance because they are painted in cooler colors which are also less intense. The blue patches tie the painting together, as well as drawing the eye through the composition. In his drawings, long lines serve the same purpose.