Engineering Surveys for Highway Alignment

For deciding the highway alignment various surveys are to be carried out. There are four main stages in engineering surveys.

a) Map Study

b) Reconnaissance survey

c) Preliminary survey

d) Final location and detailed surveys

a) Map Study: Topographical maps can be obtained from the Survey of India which can be used to understand main features like valleys, hills, rivers, lakes, etc. From these maps possible routes can be proposed of which further detailed study can be done. From this study, appropriate distances of each route can be found out too.

b) Reconnaissance Survey: This is the second stage of the engineering survey for highway alignment. The engineer visits the site and makes a feasibility study of all the proposed routes.

c) Preliminary survey: To collect adequate data to prepare a plan/map of the area to be used for planning and design.

d) Final location survey: The alignment finalized after the preliminary survey is to be first located on the field by establishing the center line. This is done accurately by using instruments. The final route selected after the preliminary survey is surveyed and located on the ground.