FAST, ACCURATE TWO-PERSON BEACH SURVEYS 



by 

 W-iltiam A. Bivkemeier 



I . INTRODUCTION 



The most desirable method of beach surveying is to use a surveying level to 

 determine elevation and a tape to measure distance; however, the procedure re- 

 quires a minimum of three people for an efficient survey. Two popular surveying 

 methods, which require only two people, are stadia surveying and Emery surveying. 

 The Emery method (Emery, 1961) -^ uses the horizon to establish a level line and 

 two 5-foot (1.5 meters) calibrated poles to measure both the distance and the 

 change in elevation between successive survey points. Since the accuracy of 

 each point is dependent on the accuracy of preceding points, large errors are 

 possible (Czerniak, 1973) . Emery's method also requires that survey points 

 be taken every 5 feet, a severe restriction on long, flat beaches. For these 

 reasons, the Emery method is not recommended. 



In a stadia survey (Davis, Foote, and Kelly, 1968)^, the elevation and dis- 

 tance to each point are determined by three readings of the surveyor's rod 

 using a surveying level located on the profile line. The readings are taken 

 from three crosshairs visible through the level's eyepiece: the center cross- 

 hair is used for elevation, and the two outside (top and bottom) crosshairs are 

 used to determine distance. Advantages are speed and the fact that each suirvey 

 point is independently determined. The primary disadvantage is that distance 

 along the profile line is indirectly measured. 



This report discusses a modified stadia surveying procedure commonly known 

 as three-wire leveling which overcomes this disadvantage, and which has proven 

 to be fast, economical, and sufficiently accurate for this type of surveying. 

 These procedures are not intended to replace traditional level and tape sur- 

 veying. They are an improvement over the Emery method and can be useful when- 

 ever only two people are available or when a quick survey is required (e.g., 

 during poststorm damage assessments) . While professional surveyors will find 

 that much of the material is a review, the report does provide some useful 

 insight into the problems of beach surveying. These procedures have been 

 developed during 3 years of extensive beach surveys before and after storms 

 where speed and accuracy were essential. 



^EMERY, K.O., "A Simple Method of Measuring Beach Profile," Limnology and 

 Oceanography^ Vol. 6, No. 1, 1961, pp. 90-93. 



^CZERNIAK, M.T., "Comparative Field Test of Three Beach Profile Survey 

 Methods," Memorandum for Record, U.S. Army, Corps of Engineers, Coastal 

 Engineering Research Center, Fort Belvoir, Va., Aug. 1973. 



^DAVIS, R.E., FOOTE, F.S., and KELLY, J.W., Surveying Theory and Practicey 

 McGraw Hill, Inc., New York, 1968. 



