Engineering Surveys associated with engineering design often require geodetic computations beyond normal civil engineering practice.
Theese surveys are usually based on horizontal and vertical control, which consists of a series of fixed points located throughout a site whose positions must be determined on some coordinate system.
Horizontal control: defines points on a two dimensional horizontal plane which covers the site.
Vertical control: is the third dimension added to the chosen horizontal datum. The measurements for the control survey are taken using different types of equipment depending on the size of the site.
In small sites typically theodolites, and tapes are used to observe horizontal control in the form of a traverse with levelling providing the vertical control.