Today, beach surveying is accomplished using a Real-Time Kinematic (RTK) Global Positioning System (GPS) that links to a network of base stations to obtain very accurate location and elevation measurements at a survey point.  These individual measurements have an accuracy of a <2 inches in the horizontal and vertical directions.  A surveyor measures a series of points across a beach, from the waterline to the landward vegetation, and this transect of points when plotted on a graph determines that beach profile -- the shape of the beach at that time (see the video below).  Repeat measurements along the same transect allow changes to be seen and calculated.  Also, a beach volume may be determined by quantifying beach cross-shore area for and alongshore distance.  

Watch this short video to learn more about the beach survey process and insights it can provide...

In the past, beaches were surveyed using a tripod-mounted survey level and stadia rod (see photo at the top and below).  The team would begin by finding a permanent stake at the site and level the survey tripod at a high point along the profile.  Then, one person would look through the survey level at the person holding the stadia rod to determine the height above the ground and the distance to the rod.  The team would measure a series of points across the beach, from the waterline to the landward vegetation, and this transect of points when plotted on a graph determine that beach profile -- the shape of the beach at that time.  Repeat measurements along the same transect allowed changes to be graphed and calculated.  This was a simple technique in theory, but it required time-consuming team coordination.  Also, careful notes were needed to ensure measurements were not missed or incorrectly recorded.  Today's method with RTK GPS is faster, easier and equally accurate.