Consider the following surveys
(i) Reconnaissance survey ,
(ii) Preliminary survey . . .
(iii) Traffic survey •
(iv) Location survey . . . .

The correct sequence of surveys conducted to finalized the railway alignment is

Explanation:

Traffic Survey

• This is conducted first to assess whether there is a need for a railway line in the proposed region.

• It evaluates passenger demand, freight movement, economic potential, and justifies the investment.

• Without this survey, there is no basis to proceed further.

Reconnaissance Survey

• After traffic demand is established, reconnaissance is done to study the terrain and physical feasibility.

• It involves field visits and map study to select broad corridors for further detailed study.

• Identifies natural obstacles like rivers, hills, existing structures.

Additional Information

Preliminary Survey

• Carried out on possible alignments identified in reconnaissance.

• Involves detailed data collection: topography, soil, water bodies, land use.

• Used to compare different routes and prepare technical and cost estimates.

Location Survey

• The final and most accurate survey, done after the alignment is finalized.

• Marks the exact centerline of the railway track on ground.

• Provides data for final design, land acquisition, and construction.