Studies / field surveys / investigations / modelling

carried out for the 

Sethusamudram Ship Channel Project

by Tuticorin Port Trust

1. Detailed EIA and Techno Economic Feasibility Studies by the National  

    Environmental Engineering Research Institute (2002 – 04)

1.Comprehensive Marine and Terrestrial Environmental Study in the Project Region

   extending from Point Calimere to Tuticorin in collaboration with Central Marine

   Fisheries Research Institute.

Ø       Primary data generated for marine water quality, sediment and marine biology at various location on the alignment options for validation of baseline marine environmental status.

Ø       In addition to primary data, secondary data related to fishery potential and socio-economic conditions collected form agencies such as MPEDA and CMFRI.;

2. Marine Environment data including physico-chemical and biological status with the

    assessment covering water and sediment furnished and analysed. The analysis

    confirmed the biodiversity richness of the Gulf of Mannar and Palk Bay, the project

    region.

3. The status of land environment was established by using satellite imageries by

    developing false colour composites using IRC, LISS and PAN images and the data,

    validated further by satellite, imageries of 2002, was used for identifying suitable

    sites for disposal of dredged material.

4. Socio-economic environment profile arrived at after analysis of secondary /

    published data supported by a rapid sample survey representing 8000-10000

    fisherman in the project region. During the random survey, public perception about

    the project was also elicited.                                     

5. Hydrographic data pertaining to tides, currents and sediment transport analysed 

    from secondary data/published literature, supported by field observations.

6. The impacts associated with the project discussed for pre-construction, construction  

    and post-construction phases, and analysed using network methods.

7. Impacts on the marine environment studied in terms of sediment transport/littoral

    movement using hydrodynamic models.

8. Methodological ocean parameters studied by the National Ship Design Research

    Centre in terms of waves, current and tides.

9. Change in met.ocean parameters due to the channel at Adam’s Bridge predicted

    using a hydrodynamic model (DIVAST 2D Ocean model). The impact of dumping

    of dredged spoil at depths of about 33-50m studied using CORMIX model. The

    first study the result of which are calibrated against actual tide and current

    measurements, indicated that construction of the channel will not lead to any

    significant change in the direction and magnitude of the current at Adam’s Bridge.

    The latter study concluded that the silty water when discharged would be localized    

   and restricted to the 1000 m from the point of discharge and that the dispersion       

   plume will not surface immediately and the concentration of the sea water will

   attain normal condition after 1000m in the line of advection. Numerical modeling of

   sediment transport caused by tidal current was carried out for Adam’s Bridge area.

10. Sea Geo surveys through the NSDRC for carrying out bathymetry and shallow

      seismic survey in the Adam’s Bridge area along the proposed alignment.

11. Bathymetry and shallow seismic surveys along the entire canal alignment by National

      Hydrographic Office (NHO), Dehradun.

12. Geotechnical investigations in select locations in water depths of 2,3 and 5m in the Adam’s Bridge area for determination of the nature of the soil parameters below the sea bed, through the NSDRC. Geotechnical investigations carried out in Palk Bay/Palk Strait and Radio Tracer Studies carried out by the Department of Atomic Energy during earlier studies relled upon for Palk Bay/ Palk Strait.

13. Traffic potential assessment by the Shipping Corporation of India.

Top               

II. Detailed Project Report by L&T Ramboll Consulting Engineers Ltd. (2004-05)

14. Bathymetric and Geophysical Surveys by NIOT using Sparker and Boomer sesmic system and parametric sub-bottom profiling along the alignment of the channel to assess the nature of sub-surface below the sea bed and for confirming the selected alignment. The penetration obtained was of the order of 40m below seabed. Bathymetry data was acquired using a ODOM Echo Track Dual frequency echo sounder. The surveys were carried out for a corridor width of 500m on both sides of the Center line of proposed alignment at a spacing of 150m apart. The survey vessel was accurately positioned using Leica DGPS with RTCM corrections from “OMNISTAR”

In order to apply tidal corrections NIOT had installed 3 tidal stations at Nagapattinam, Pamban Pass and Sethubavachatram and tides were measured for 30 days. NIOT with the data generated carried out a Tidal Propagation model using MIKE21, the output of which was used to reduce the bathymetry to chart datum along various segments of the channel

15. Geotechnical investigations were carried out by NIOT along the entire alignment with 44 vibro-coring operations by deploying 6m long core lines. All the cores were analysed by NIOT for their geotechnical properties with some of the samples tested for calcium carbonate and organic contents.

16. NIOT have carried out ten minutes boreholes in locations where vibro-coring could not by carried out due to shallow depth. The scattered islands near the channel alignment and also the channel alignment were the selected locations.

17. Hydrodynamic modeling, sedimentation studies and Ship Manoeuring Study by M/s. Indomer Coastal Hydraulics (P) Ltd., in association with M/s. Alkyon Hydraulics, The Netherlands. The hydrodynamic modeling and sedimentation study consisted of the following components:-

• A wave study using SWAN-module in the Delft 3D suite, wave climate through out the length of navigation for input to subsequent studies relating to channel siltation, flow modeling and ship manoeuvring.

• A tidal flow model study using Delft 3D package of WL/Delft Hydraulics to determine tidal currents velocity and direction along the alignment of the channel and anchorages.

• A sedimentation study using the UNIBEST-LT model to determine the siltation pattern and quantum of annual maintenance dredging for the channel and anchorages.

• The alignment of the channel was the input used for the Ship Maneuvering and channel depth study. Simulations were carried out for two types of vessels viz. bulk carries and container vessels with LOA 215m, beam 33m and Draft 10m. Real time maneuvering simulations were carried out using Alkyon’s real -time simulator SHIP-navigation while the channel depth study was carried out using the mathematical model SEAWAY.

18. Detailed Project Report including inter-alia-

1. Review and validation of NEERI’s proposal for channel alignment.

2. Traffic Forecast & vessel size analysis.

3. Channel design and dimensions.

4. Identification of dredging requirements.

5. Assessment of ancillary facilities requirement.

6. Vessel Traffic Management System, Flotilla and Navigation aids.

7. Assessment of EIA Studies of NEERI and Detailed EMP.

8. Cost estimates and project implementation schedule.

9. Traffic analysis and Project structures.

10. Risk analysis.

11. Financial and Economic Viability analysis.

The DPR includes independent data on geomorphology of the region, climate, wave conditions, cyclones and depressions, waves, tides, longshore currents and littoral processes along Rameswaram Island and surface circulation, compiled by the DPR consultants from sources other than NEERI.

Top               

  Home