--- title: "Stages of engineering survey for alignment" subject: "Transportation Engineering I" chapter: 2 key: "semester_6/transportation_engineering_i:survey-stages" source: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/survey-stages site: BCT Engineering --- # Stages of engineering survey for alignment Transportation Engineering I · Chapter 2: Highway Alignment and Engineering Survey - Asked in: 2078 Poush, 4 marks; 2075 Bhadra; 2074 Bhadra, 8 marks; 2072 Ashwin; 2071 Magh, 8 marks; 2068 Bhadra (old course); 2067 Mangsir (old course) (asked 7 times) - Video: [Engineering Survey For Highway Alignment - Transportation Engineering - I](https://www.youtube.com/watch?v=li2lMLzcCwU) — Ekeeda - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_6/transportation_engineering_i/survey-stages - Whole chapter: https://www.bctengineer.com/md/semester_6/transportation_engineering_i/chapter-2 ## Question Explain the different stages of engineering survey for highway alignment. ## Short answer Alignment surveys proceed in four stages: map study identifies broad routes from maps; reconnaissance quickly verifies them in the field; preliminary survey collects detailed topographic and soil data on one to three routes; final location surveys set the exact centre line and produce construction drawings. ## Answer To fix the best alignment, the engineering survey is done in stages, moving from broad study to detailed work. Each stage narrows the options. #### 1. Map study - Using topographic maps (1:25,000 or 1:50,000), satellite images or aerial photographs, the possible routes are marked between the terminals through the obligatory points. Ridge lines, valleys, river crossings, passes and obstructions are studied. - Gives alternative alignments at low cost. #### 2. Reconnaissance survey - A quick field examination of the routes picked on the map, on foot or by vehicle, with simple instruments (abney level, compass, tape, altimeter). - Collects: topography, geology, drainage and stream crossing, soil, materials, land use, climate/rainfall, settlements, forests, cost of land. - Rough estimates of cost; best routes (one to three) are selected. #### 3. Preliminary survey - A detailed survey of the selected route(s) to compare and fix the final one: a traverse with a theodolite/total station, levelling along it, contouring of a strip (a 100-200 m belt), cross-sections, stream data, soil and material survey, drainage and traffic data. - Output: contour plan, preliminary estimate and comparison of alternatives. #### 4. Final location and detailed survey - The chosen alignment is fixed on the ground using the plan from the preliminary survey: centre line pegging, curves set out, bench marks, profile and cross-sections, soil and material tests, hydrological data. - Detailed drawings, bill of quantities and cost estimate for tender. ```text Map study -> Reconnaissance -> Preliminary -> Final location (paper) (field, quick) (detail) (set-out, design) many routes 2-3 routes 1-2 routes 1 alignment ``` ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. Which is the correct order of highway alignment survey stages? A. Reconnaissance, map study, preliminary, final location B. Map study, reconnaissance, preliminary, final location C. Map study, preliminary, reconnaissance, final location D. Preliminary, map study, reconnaissance, final location Answer: B. Survey moves from broad paper study to detailed ground work: map study, reconnaissance, preliminary survey, final location. (Key point: Order of stages) 2. What is done in the map study stage? A. Centre line is pegged on the ground B. Possible routes are marked on topographic maps or photos through obligatory points C. Soil CBR tests are done along the route D. Bill of quantities is prepared Answer: B. Map study marks alternative routes on maps/aerial photos at low cost, before any field work. (Key point: Purpose of map study) 3. What is the result of the reconnaissance survey? A. A single final centre line B. A bill of quantities for tender C. A quick field check with simple instruments and selection of one to three best routes D. A 100-200 m wide contour plan with theodolite traverse Answer: C. Reconnaissance is a quick field examination with simple instruments that rough-estimates costs and keeps 1-3 routes. (Key point: Reconnaissance outcome) 4. Which work belongs to the preliminary survey? A. Traverse with theodolite/total station, levelling and contouring of a strip B. Selecting routes from satellite images C. Setting out curves and pegging the centre line D. Estimating cost from the map only Answer: A. Preliminary survey is a detailed instrumental survey of the selected route(s) giving a contour plan and estimate for comparison. (Key point: Preliminary survey) ## Related in Transportation Engineering I - [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× - [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× - [Scope of highway engineering](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Ascope-highway-engineering) — Transportation Engineering I, chapter 1, asked 3× - [Preliminary survey method](https://www.bctengineer.com/question.md?key=semester_6%2Ftransportation_engineering_i%3Apreliminary-survey) — 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 - [Unconformity: stages and engineering significance](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Aunconformity-stages-and-engineering-significance) — Engineering Geology I, chapter 5 - [Geology in road alignment selection](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Aroad-alignment-geology) — Engineering Geology II, chapter 4, asked 5× - [Direct surface methods for road alignment](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Adirect-surface-methods-road) — Engineering Geology II, chapter 4