---
title: "Final location and detailed survey"
subject: "Transportation Engineering I"
chapter: 2
key: "semester_6/transportation_engineering_i:detailed-survey"
source: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/detailed-survey
site: BCT Engineering
---

# Final location and detailed survey

Transportation Engineering I · Chapter 2: Highway Alignment and Engineering Survey

- Asked in: 2081 Ashwin, 5 marks; 2075 Baisakh; 2065 Chaitra (old course), 6 marks (asked 3 times)
- Video: [Highway location survey | Survey for highway location | Highway Engineering🔥🔥](https://www.youtube.com/watch?v=Oku3oH1Q3qo) — Civil Notebook
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/detailed-survey
- Whole chapter: https://www.bctengineer.com/md/semester_6/transportation_engineering_i/chapter-2

## Question

Explain the final location and detailed engineering survey of highway alignment: the process, the works to be carried out and the data to be collected.

## Short answer

The chosen centre line is set out on the ground with curves and reference pillars; final profiles and cross-sections are taken. Detailed topographic, soil, hydrological, geological, and material surveys are carried out to produce construction drawings, bill of quantities, and tender documents.

## Answer

The final location and detailed survey transfers the alignment chosen in the preliminary survey to the ground and collects all the data needed for design, estimating and construction.

#### Process
1. **Location of the centre line:** the centre line from the plan is set out with a theodolite/total station and fixed by pegs at about 50 m intervals in plain and rolling terrain and 20 m in hilly terrain.
2. **Setting out of curves:** tangents are fixed at the points of intersection; circular and transition curves are set out by deflection angles/coordinates, and the curve data are recorded.
3. **Levelling:** the final longitudinal profile; cross-sections at about 50-100 m intervals in plains, 50-75 m in rolling and 20 m in hilly terrain (and at changes of slope); temporary bench marks at about every 250 m.
4. **Reference pillars** are fixed outside the construction limits so that the centre line can be restored.

#### Works to be carried out
- **Detailed topographic survey** at bridges, intersections, hairpin bends and difficult sections (scale 1:500 to 1:1000 near structures).
- **Soil survey:** soil testing for the subgrade and for borrow areas; CBR values.
- **Hydrological survey:** catchment area, flood levels, discharge and waterway needs for culverts and bridges.
- **Geological/geotechnical investigation** for slopes, cuts and fills, and the foundations of structures.
- **Material survey:** quarries, sand, aggregates, water and their lead distances.
- **Land and property survey:** land boundaries, structures to be removed, utility lines.
- **Traffic survey** if required.

#### Data collected and outputs
Plan and profile drawings, cross-sections, culvert/bridge details, soil data, material sources, quantities, cost estimate, specifications and tender documents.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. How is the centre line located in final location survey?
   A. Set out from the preliminary plan with a theodolite/total station and fixed by pegs at about 20 m intervals
   B. By visual estimate
   C. From satellite maps alone
   D. By river course
   Answer: A. The centre line from the plan is transferred to the ground and pegged at 20 m (30 m in plains). (Key point: Centre line pegging)

2. Why are reference pillars fixed outside the construction limits?
   A. To mark the land boundary
   B. To mark quarry sites
   C. To restore the centre line later during construction
   D. To measure traffic
   Answer: C. Pillars outside construction limits let the centre line be re-established after earthwork disturbs the pegs. (Key point: Reference pillars)

3. Which is part of the works in the detailed survey?
   A. Selecting terminals
   B. Choosing between region and band
   C. Rough cost from map study
   D. Hydrological survey of catchment, flood level and discharge for culverts and bridges
   Answer: D. Hydrological, soil, geological, material, land and traffic surveys are done for design. (Key point: Works to be carried out)

4. Which are outputs of the final location and detailed survey?
   A. Plan and profile drawings, cross-sections, quantities, estimate and tender documents
   B. Only rough route lengths
   C. Only a map study report
   D. Only a traffic count
   Answer: A. The survey ends with drawings, quantities, cost estimate and tender documents. (Key point: Outputs)

## Related in Transportation Engineering I

- [Stages of engineering survey for alignment](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Asurvey-stages) — Transportation Engineering I, chapter 2, asked 7×
- [Requirements of ideal highway alignment](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Aalignment-requirements) — Transportation Engineering I, chapter 2, asked 12×
- [Factors controlling highway alignment](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Aalignment-factors) — Transportation Engineering I, chapter 2, asked 12×
- [Definition of highway alignment](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Adefine-alignment) — Transportation Engineering I, chapter 2, asked 4×
- [Structure of route location process](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Astructure-route-location) — Transportation Engineering I, chapter 2, asked 5×
- [Updating information across survey stages](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Ainfo-updated-stages) — Transportation Engineering I, chapter 2, asked 3×

## Related in other subjects

- [Tunnel alignment survey and ideal bridge location](https://www.bctengineer.com/question.md?key=semester_7%2Ftransportation_engineering_ii%3Atunnel-alignment-survey-ideal-bridge-location) — Transportation Engineering II, chapter 5
- [Data required for detailed estimate](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Adata-for-detailed-estimate) — Estimating and Costing, chapter 1
- [Principle of units; data for detailed estimate](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Aprinciple-units-data-required) — Estimating and Costing, chapter 1
- [Contract types in civil engineering; govt works](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Acontract-types-government) — Construction Management, chapter 5