(8) References . The distances and angles from each monument to its 

 referencing points, as well as the elevations of reference points, should be 

 provided. 



(9) Distance Between Profiles . The distances and azimuths between pro- 

 file lines must be provided if grid coordinates are not given. 



(10) Photos . Photos should be taken of each monument and its vicinity 

 to assist in its description. The general direction of each photo should be 

 noted. When possible, aerial photography should be acquired to show the base 

 line, which should be marked so that points are visible on the photos. 



b. Data on Profile Lines . 



(1) Azimuth . The azimuth of each profile line from land to sea should 

 be provided. It may be referenced to any standard, such as true north or the 

 base line, as long as the standard is consistent between profile lines and 

 throughout the study. 



(2) Change in Location . The date and details of any change in the lo- 

 cation or orientation of a profile should be added to the documentation. 



(3) Photos . Photos taken looking seaward from the survey control point, 

 landward and seaward from other significant features, and landward from the 

 waterline are useful in the description of the profile if they show stable, iden- 

 tifiable features. 



(4) Directions . In order to survey a profile line, it must first be 

 found by the surveyor. Written directions or a map should be provided to each 

 monument from the main routes of access. 



IV . SUMMARY 



The proper monumenting, referencing, and documenting of base line and pro- 

 file lines is cost effective, ensures the viability of the profile data through- 

 out the study period, and allows the reoccupation of profile lines years after 

 their establishment. The proper establishment of base lines and profile lines, 

 which is a requirement for a good study, reduces the chance for misinterpreta- 

 tion of the data and supports the accuracy of the data obtained. 



be; 



When establishing base lines and profile lines, the moniiments should 



(a) Made relatively permanent by (1) locating the monuments far 

 enough back from the shore to be in a stable area, and (2) pro- 

 tecting the monuments from vandalism. 



(b) Located horizontally with enough redundancy to ensure rees- 

 tablishment if lost or destroyed. 



(c) Located vertically such that their elevation with respect to 

 other bench marks and datums, such as a tidal datum, is known. 



(d) Checked periodically for location and elevation. 



(e) Documented carefully, both when originally established and 

 if updated or changed. 



15 



