---
title: "Reconnaissance survey information"
subject: "Transportation Engineering I"
chapter: 2
key: "semester_6/transportation_engineering_i:recon-survey-info"
source: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/recon-survey-info
site: BCT Engineering
---

# Reconnaissance survey information

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

- Asked in: 2069 Bhadra; 2067 Mangsir (old course) (asked 2 times)
- Video: [Reconnaissance Survey And Index Sketch](https://www.youtube.com/watch?v=xuLFUmiL9D4) — For The Engineer
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/recon-survey-info
- Whole chapter: https://www.bctengineer.com/md/semester_6/transportation_engineering_i/chapter-2

## Question

Describe the information to be collected during reconnaissance survey.

## Short answer

Reconnaissance collects field data on terrain, stream crossings and flood levels, soil type and geology, drainage, land use, construction material sources, climate, land cost, existing infrastructure, and social impacts, using simple instruments like abney level, compass, and GPS.

## Answer

Reconnaissance is a rapid field study of the alternative routes that were picked in the map study. The following information is collected.

1. **Topography:** general terrain, ridges, valleys, cross-slopes, possible gradients, mountain passes.
2. **Streams and rivers:** number and size of stream crossings, high flood level, river course, bed material, suitable bridge sites.
3. **Soil:** type of soil (clay, silt, sand, rock), suitability as subgrade, swamp or black cotton soil.
4. **Geology:** rock type, landslide zones, faults, unstable slopes.
5. **Drainage conditions:** water table, flooding, seasonal streams.
6. **Land use:** forests, farms, settlements, graveyards, religious sites, protected areas.
7. **Construction materials:** quarries, sand and aggregate sources, water and the lead distance.
8. **Climate:** rainfall, snow, fog, wind, temperature.
9. **Existing roads and bridges,** their conditions and possible use.
10. **Cost of land and property,** utilities (electric, telephone, pipes) to be shifted.
11. **Labour and equipment availability,** and accessibility to the site.
12. **Social and environmental aspects,** e.g. effect on local people.

Instruments used: Abney level, compass, tape, pocket altimeter, GPS and camera. The final output is a comparison of the routes with rough lengths and cost, from which 1-3 are selected for the preliminary survey.

## Check yourself

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

1. What kind of survey is reconnaissance?
   A. A detailed theodolite survey
   B. A rapid field study of the routes picked in the map study
   C. A paper study only
   D. A tender survey
   Answer: B. Reconnaissance is a quick field study of alternatives chosen from maps. (Key point: Nature of recon)

2. Which set is collected during reconnaissance?
   A. Detailed contour interval and bill of quantities
   B. Only traffic counts
   C. Topography, streams, soil, geology, drainage, land use, materials and climate
   D. Only the cost of pavement
   Answer: C. It collects topography, stream crossings, soil, geology, drainage, land use, materials, climate, existing roads and cost of land, etc. (Key point: Data collected)

3. Which instruments are typically used in reconnaissance?
   A. Abney level, compass, tape, altimeter, GPS
   B. Theodolite with total traverse only
   C. Concrete test hammer
   D. Plate load apparatus
   Answer: A. Simple instruments such as Abney level, compass, tape and pocket altimeter are used. (Key point: Instruments)

4. What is the final output of reconnaissance?
   A. Tender documents
   B. A comparison of routes with rough length and cost, selecting 1-3 for preliminary survey
   C. Setting out of curves
   D. Final cross-sections
   Answer: B. Routes are compared with rough lengths and costs, and 1-3 go to preliminary survey. (Key point: Output)

## Related in Transportation Engineering I

- [Why reconnaissance survey is conducted](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Arecon-survey-why) — Transportation Engineering I, chapter 2
- [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×
- [Final location and detailed survey](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Adetailed-survey) — Transportation Engineering I, chapter 2, asked 3×

## Related in other subjects

- [Studies in reconnaissance, pre-feasibility, feasibility](https://www.bctengineer.com/question.md?key=semester_7%2Fhydropower_engineering%3Arecon-prefeas-feas-studies) — Hydropower Engineering, chapter 2, asked 3×
- [Average demand, village survey 2013, design 25 years](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Ademand-c73) — Water Supply Engineering, chapter 3, asked 2×
- [Total demand, village survey 2013, design 15 years](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Ademand-c69) — Water Supply Engineering, chapter 3, asked 2×
- [Ethnographic survey and its methods](https://www.bctengineer.com/question.md?key=semester_7%2Ftechnology_environment_and_society%3Aethnographic-survey-methods) — Technology, Environment and Society, chapter 2