Transformation of Triangulation Points to Geotechnical Investigation Area related to the Feasibility Study

Project Description

Tamaksohi -3 (TA-3) and Tamakoshi- 2 (TA-2) Hydroelectric Project is located on the Tamaksohi River in Dolakha district of central Nepal and is conducting the Feasibility Study and Environmental-Social Impact Assessment Study (ESIA) after receiving survey license from Government of Nepal. The Project intends to develop these two projects as combined TA-23. The objective of the work is to transform the x,y, and z coordinates in the geotechnical investigation areas for preliminary site investigations related to the feasibility Study.

Assignment Description

Reconnaissance Survey and identification of the survey area • Identification of 2nd, 3rd, and 4th order triangulation points established by Department of Survey, Geodetic Branch in the Project area. • Establishment of permanent benchmark in the close vicinity of the dam location/s • Preparation of D-cards including color photographs of the BM’s with sufficient ground details in the captured photographs • Traffic and Axle Load including road data collection/survey • Transformation of triangulation points using Total Station including field data computations • Horizontal (x, and y coordinates) transferring through closed traverse survey originating and terminating at main control station of second/third order • Vertical controls (z co-ordinate) by trigonometric leveling/differential leveling as appropriate based upon site condition and accessibility. The accuracy of the survey achieved was within +/- 20 mm from the control points or as appropriate based on standard formulae of the loop distance • Traverse drawings in the 1:10,000 scale maps including error distribution • Plotting of coordinates in the 1:25,000 scale topographic maps and checking including error distribution within +/- 5 cm.