Chennai-Bengaluru bullet train project enters next phase with fresh tender

CHENNAI: Planning for the proposed Chennai-Bengaluru bullet train has entered the next stage, with the National High Speed Rail Corporation Ltd (NHSRCL) taking steps to update the project's detailed project report (DPR) and undertake fresh engineering surveys along the corridor.

Parandur station retained despite airport uncertainty

Incidentally, the documents show that the plan for the 306.2-km Chennai-Bengaluru section has retained Parandur station though the State government has decided to scrap the plan to set up a greenfield airport there. The section will run through Chennai, Poonamallee, and Parandur in Tamil Nadu; Chittoor and Bangarupalem in Andhra Pradesh; and Kolar, Malur, Whitefield, and Bengaluru in Karnataka.

The station in Chennai has been planned as an underground facility adjacent to MGR Chennai Central railway station with connectivity to the Metro Rail. In Poonamallee, the proposal is to set up an elevated station on the northern side of National Highway-4 with connectivity to the Outer Ring Road, Metro Phase II, Chennai airport, and the city centre.

Parandur has again been identified as an elevated station on the southern side of the greenfield airport that is now hanging in balance, with connectivity to the Bengaluru-Chennai Expressway, NH-48, and the Outer Ring Road through connector roads.

Fresh DPR and engineering surveys planned

The scope of work includes validation of the existing DPR, alignment modification and design, hydrology investigations, drone and LiDAR surveys, geotechnical investigations at crossing locations, tunnel studies, preparation of general arrangement drawings (GADs) for river, railway and road crossings, and station surveys for both elevated and underground stations. As per the tender, the DPR preparation and engineering survey should be completed within 150 days.

The NHSRCL prepared and submitted the DPR for the Chennai-Bengaluru-Mysuru High-Speed Rail corridor in September 2024. The Chennai-Bengaluru section has since been identified as Phase I and the priority stretch of the larger corridor.

Alignment review between Chennai Central and Poonamallee

It also seeks a detailed review of the alignment between MGR Chennai Central and Poonamallee. The consultant should review river crossings, road crossings, station locations, and other engineering features before finalising the preferred alignment. Preliminary designs and GADs for major river crossings, railway crossings, road crossings, tunnels, and stations should also be prepared.

Detailed studies for river crossings

For the Tamil Nadu section, the tender identifies major river crossings requiring detailed hydrological investigations. These are the Cooum, Kaveripakkam/Kosasthalai, Ponnai/Bahuda, and Palar rivers. The consultant has been asked to collect high flood level data, prepare river cross-sections, survey riverbeds and floodplains, and assess flow characteristics before bridge designs are finalised.

The preliminary design package also identifies several major crossings in the Chennai section requiring general arrangement drawings, including two crossings over the Perambur Loco Works sidings and one over the Integral Coach Factory (ICF) siding, besides major river crossings along the corridor.

Data collection and land acquisition plans

As part of the exercise, the consultant has been directed to collect data from the Public Works Department, Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB), Tamil Nadu Water Supply and Drainage (TWAD) Board, urban local bodies, municipal corporations, and municipalities along the corridor.

This includes details of water supply and sewerage infrastructure, approved layouts, master plans, transport corridors, utilities, and other data that may influence the final alignment. The consultant has also been asked to prepare updated land acquisition plans wherever changes to the alignment are proposed after the surveys and investigations.