Differential Leveling

level instrument and measuring rod on the Engineering Meadow near the CLA building


This interactive simulation will introduce you to the iterative 4-step process of differential leveling:

  • take a backsight measurement (BS)
  • move the rod
  • take a foresight measurement (FS)
  • move the instrument

At each turning point (TP) you will calculate the height of the instrument (HI) and the elevation (Elev) for that point.

Learning Objectives

Upon completion of this simulation, you will be able to:

  • Determine the elevation of a Temporary Benchmark (TBM)
  • Calculate the Height of the Instrument and Elevation at a Turning Point
  • Identify when to take a Backsight or Foresight measurement
  • Choose when the measuring rod should be moved versus when the instrument should be moved

Select the "Simulation" tab above to begin.

Differential Leveling

Field Notebook
+BSBacksight measurement
HIHeight of Instrument
-FSForesight measurement
BM      bmElv Benchmark
TP1      Random
TP2      Random
TP3      Random
TP4      Random
TP5      Random
TP6/TBM      RR Spike
ΣBS= ΣFS=   

Page Check

BM elev + ΣBS - ΣFS =


Omar Mora

Dr. Omar E. Mora is an assistant professor in the Civil Engineering Department at Cal Poly Pomona. He received his PhD degree from The Ohio State University in 2015, MS degree from Purdue University in 2010 and BS degree from Cal Poly Pomona in 2007. His current research emphasis is on surface model generation, surface extraction, change detection, close-range photogrammetry, laser scanning technologies and the development of algorithms for the practical use in 3-D mapping, modeling, classification, detection, and object-based image analysis (OBIA).

Donya Rahimi

Donya Rahimi is an Instructional Designer for the Center for the Advancement of Faculty Excellence (CAFE) at California State Polytechnic University, Pomona. She provides instructional design consultation to assist faculty in redesigning existing courses and developing new courses for online, hybrid and face-to-face modes of instruction.

Richard Feldman

Richard Feldman is a multimedia developer for the Center for the Advancement of Faculty Excellence (CAFE) at California State Polytechnic University, Pomona. He creates interactive simulations that help faculty demonstrate concepts that are otherwise difficult to explain to students.

Other Credits: Additional contributions were made by Bo Choi, Instructional Designer.

Unless otherwise specified, all images, graphics, and content in this simulation are property of California State Polytechnic University, Pomona.