So in this scene we have a Arizona wash the have a bridge. The bridge is from Campbell Scale Model kit 305, Howe Truss Bridge Kit.
So the base is made from plaster with a brick form to give it the brick look. Don’t forget if you us a periocular look on one pier or wall. You need to keep that look the same on the abutments.
So below on the ground we used a mix of 11003 High Desert Sand & Gravel with 1284 Smooth Stone and some foliage. The larger rock nest next to the abutments are 1305 Northern Pacific Gray Model Railroad rocks. The rocks to the left of the pier is some rock from the 1285 Smooth stones and 201 BNO Rail Yard rocks.