Final Location Survey
1. Terms of Reference
The Project Investigator should be supplied by the Railway Administration with “Terms of Reference” as indicated in para 209.
2. Field Work
A Final Location Survey should be based on a good theodolite or traverse, which should approximate as closely as possible to the centerline to be finally adopted.
3. Scope of Survey Operations
Unless otherwise specified, the survey operations should be sufficiently comprehensive to secure the information necessary for the preparation of the detailed plans and sections required under paragraph 443 et seq. and, having regard to all the circumstances of the case (including the probable working expenses), to ensure that the alignment selected is the most economical obtainable.
4. Detail in Sectioning
The amount of detail in sectioning will, to a great extent, depend on the nature of the country traversed. Cross sections should be taken wherever the Engineer considers them necessary. The information collected during the course of the survey should enable the preparation of a fairly accurate estimate of the cost of the line.
5. Investigation of Nearby Irrigation Works
Investigations should be made of bunds, bunded streams, and irrigation works in the vicinity of the projected line which might affect the future safety of the line. Decisions on waterways should consider these works and weigh the option of altering or diverting bunds, irrigation streams, etc., even if this incurs some expenditure, provided it saves a larger expense on waterways.
6. Geological Characteristics in Hills
In the case of passage through hills, the geological characteristics of the area should be investigated, particularly regarding the probable stability of the line. If the work is significant, the Railway Administration should seek the assistance of the Geological Survey of India.
7. Soil Sampling and Testing
A systematic soil sampling program should be carried out at suitable intervals and depths along the proposed route. Samples should also be collected from borrow areas and tested for standard properties. Bore logs should be prepared, and the data should guide the design of embankments, cutting profiles, and the methods for undertaking earthwork.
8. Notes to be Made in the Field
During the survey, careful notes with dates should be made on the ground from personal inquiry and observation regarding any information likely to be useful in working out the project details.
9. The Centre Line
The unit of measurement for the centerline should be the chain of 20 meters. Pegs marking every 20 meters and larger pegs at 100-meter intervals, branded with numbers, should indicate distances from the zero chainage.
10. Masonry Pillars and Curve Descriptions
Masonry pillars should be built at tangent points of curves and intervals of not less than 500 meters. Curves should be described by their radius of curvature in meters and their degree of curvature.
11. Transition Curves and Gradients
Transition curves should be used for changes in curvature. Gradients should be graded with provision for future intermediate stations. Sharp gradient changes, especially on curves, should be eased off by vertical curves. Compensation for curvature should be applied as per the gauge.
12. Benchmarks
Benchmarks should be left at intervals of not more than 1 kilometer, constructed to withstand damage, and marked for easy identification. Levels should refer to the Mean Sea Level (MSL).
13. Compass Bearings
Compass bearings of each tangent should be recorded in level country, while in hilly regions, bearings at 2-3 places per kilometer suffice.
14. Plans, Sections, and Designs for Works
A complete set of project plans and sections should include:
(i) General Map
(ii) Index Map
(iii) Index Plans and Sections
(iv) Detailed Plans and Sections
(v) Plans and Cross Sections
(vi) Plans of Station Yards
(vii) Detailed Drawings of Structures
(viii) Plans of Junction Arrangements
15. Preparation of Detailed Plans and Sections
Plans should depict topographical details within 100 meters of the centerline, while detailed sections should reflect formation levels, gradients, and structures. Special care should ensure alignment accuracy and clarity of represented details.
16. Tunnels and Stations
Tunnels should be drawn to scale, indicating their lengths in meters. Stations should be demarcated with vertical red lines, and their names and yard lengths noted.
17. Key Observations for Waterways and Crossings
The bed level and high flood levels of rivers and streams should be marked. Special attention should be given to bridges, culverts, and diversion points for roads and waterways.
18. General Accuracy in Design and Data Collection
All measurements, calculations, and design details should prioritize accuracy to avoid errors that could result in increased costs or unsafe alignments. Attention must be paid to precise surveying and marking.
19. Supplementary Investigations
Additional investigations should be conducted where necessary, such as:
- Subsoil Investigations: Borehole data, soil tests, and hydrological data to determine load-bearing capacities.
- Climatic Studies: Information on rainfall, temperature variations, and other climatic factors to influence drainage and structural design.
- Hydrological Surveys: Detailed analysis of water flow, flood records, and expected future changes to waterways.
20. Cost Estimation and Budgeting
The final location survey should provide data for preparing a detailed cost estimate of the project. Cost elements to be addressed include:
- Earthwork and embankment material costs.
- Bridge, culvert, and tunnel construction.
- Station buildings, yards, and other facilities.
- Land acquisition and resettlement costs.
- Track laying and signaling systems.
21. Public and Environmental Considerations
Before finalizing the alignment, ensure compliance with environmental regulations. Conduct consultations with local communities to address concerns related to land acquisition and ecological impacts. Identify environmentally sensitive zones and mitigate impacts through alternative alignments or protective measures.
22. Preparation of Final Report
A comprehensive report must accompany the detailed plans and sections. The report should include:
- Summary of the survey process and findings.
- Justification for the chosen alignment.
- Description of major design decisions.
- Economic feasibility analysis.
- Recommendations for future stages of the project.
23. Safety Standards
The survey must account for safety considerations, including the distance from hazardous areas, stability of slopes, and safe crossing designs for roads, pipelines, and utility corridors.
24. Final Approval Process
All plans, sections, and the final report must be reviewed and approved by the competent authority of the Railway Administration. Suggested changes must be incorporated promptly to ensure alignment with regulations and project requirements.
25. Archival and Reference Records
All records from the final location survey, including field notes, design sketches, and calculations, should be archived systematically. This ensures future reference during construction, maintenance, or modifications.
26. Training and Knowledge Sharing
The survey team should document learnings and share insights gained during the process. This can help in enhancing institutional knowledge and refining methodologies for future surveys. Conducting workshops and training sessions for relevant staff ensures consistency in standards and practices.
27. Integration of Modern Technologies
To improve efficiency and accuracy, advanced technologies like LiDAR, GIS mapping, and satellite imagery should be utilized where possible. These tools provide better visualization, faster data collection, and improved analysis for finalizing alignments.
28. Communication with Stakeholders
Regular updates and discussions with key stakeholders—such as local authorities, environmental agencies, and financial institutions—ensure smooth coordination. Transparent communication helps in resolving conflicts and securing approvals without delays.
29. Review for Compliance
Before final submission, a comprehensive review should be conducted to ensure the survey complies with all statutory and regulatory requirements. This includes adherence to environmental laws, safety norms, and technical standards set by railway authorities.
30. Conclusion and Handover
The final stage involves a detailed presentation of findings, recommendations, and the selected alignment to the railway administration and project stakeholders. All materials, including maps, sections, and reports, should be formally handed over, marking the conclusion of the Final Location Survey phase.
With these additional points, the Final Location Survey documentation is now complete, covering all necessary technical, environmental, safety, and administrative considerations. Let me know if there’s any specific area you want to dive deeper into!
[…] which offer broad, conceptual ideas of possible routes, the FLS provides highly accurate data to finalize the track’s location, ensuring that the construction of the line is feasible in every aspect. It integrates data from […]