Mazagon Dock Shipbuilders Limited
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MAZAGON DOCK SHIPBUILDERS LIMITED FEASIBILITY STUDIES FOR THE PROPOSED EXTENSION OF NAVIGATIONAL CHANNEL AT MAZAGON DOCK, MUMBAI FEASIBILITY REPORT WAPCOS Limited (A GOVERNMENT OF INDIA UNDERTAKING) Swastik, Gulmohar Path, Near SNDT College, Erandawane, Pune-411004 : 020 - 25444796 Fax : 020 – 25444600 Email : [email protected] August - 2017 Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai TABLE OF CONTENTS No. PARTICULARS Pg. No. Executive Summary i Chapter 1 : Introduction 1.0 Introduction 1 1.1 Brief History 3 1.2 Scope of Work 5 1.2.1 Objective of the Study 5 1.3 Organisation of the Report 5 Chapter 2 : Site Condition 2.1 Site Condition 6 2.2 Bathymetry 6 2.3 Wind 7 2.3.1 Offshore Wind Data 7 2.3.2 Inshore Wind Data 7 2.4 Tides 8 2.5 Current 8 2.6 Wave 9 2.7 Relative Humidity 9 2.8 Temperature and Salinity 9 2.9 Rainfall 10 2.10 Bed and Water Samples 10 Chapter 3 : Field Survey and Investigation 3.1 General 11 3.2 Bathymetry 11 3.3 Field Data Collection for Monsoon Season 12 3.3.1 Tides 12 3.3.2 Current 14 Final Report Page i Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai 3.3.3 Water Sample 14 3.4 Field Data Collection for Non-Monsoon Season 15 3.4.1 Tides 15 3.4.2 Current 16 3.4.3 Water Sample 16 3.4.4 Bed Sample 16 Comparison of Monsoon with Non-Monsoon 3.5 17 Observations 3.5.1 Tide 17 3.5.2 Currents 17 3.6 Geotechnical Investigation 19 3.6.1 Exploration Program 20 3.7 Subsurface Profile 21 Chapter 4 : Mathematical Model Studies carried out at CWPRS, Pune 4.1 General 23 Mathematical Model Studies for Hydrodynamics 4.2 23 and Siltation 4.2.1 Recommendations by CWPRS 24 Mathematical Model Studies for Wave Transformation and Assessment of Wave 4.3 25 Condition along Proposed Extension of Navigational Channel 4.3.1 Recommendations by CWPRS 26 Desk Studies for Design of Proposed Extension of 4.4 27 Navigational Channel 4.4.1 Recommendations by CWPRS 27 Mathematical Model Studies to Assess Feasibility 4.5 of Flood Dumping Ground for Disposal of Dredged 28 Material 4.5.1 Recommendations by CWPRS 29 4.6 Seismic Sub Bottom Profile Studies 29 4.6.1 Conclusions made by CWPRS 30 Chapter 5 : Budgetary Cost 5.1 Basis of Cost Estimates 31 Final Report Page ii Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai 5.1.1 Dredgers 31 5.1.2 Methodology 32 5.1.3 Disposal of Dredged Material 32 5.1.4 Additional Work 33 5.1.5 Maintenance Dredging 35 5.2 Basis of Cost Estimates 35 5.3 Calculation of Cost Estimate 37 Chapter 6 : Concluding Remarks & Recommendations Final Report Page iii Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai LIST OF FIGURES No. PARTICULARS Pg. No. Proposed Layouts of Navigational Channel from Figure A iv MDL up to OCT Berth (Option I and Option II) Proposed Layout of Navigational Channel from Figure B v MDL to OCT Berth – Option III Location Plan of Mazgaon Dock Shipyard at Figure 1.1 1 Mumbai Figure 1.2 Depth Requirement Proposed by MDL 4 Tentative Alignment of Navigational Channel from Figure 1.3 4 MDL to OCT Bathymetry survey carried out for studies (Year Figure 2.1 7 2015) Bathymetry Survey carried out for Studies (Year Figure 3.1 12 2015) Locations of tide and current measurements in Figure 3.2 13 Mumbai Harbour Tide graph at BPX- MbPT, Ambuja Jetty, Vashi Figure 3.3 14 Bridge and Rewas Jetty during springs Tide graph at BPX- MbPT, Ambuja Jetty, Vashi Figure 3.4 15 Bridge and Rewas Jetty during springs Figure 3.5 Locations of Marine Boreholes (BH-1 to BH-08) 20 The final layout confirmed by CWPRS through Figure 4.1 25 hydrodynamic and siltation studies Figure 5.1 The locations and coordinates of the boreholes 34 Sub bottom profile of soil and rock bed w.r.t CD Figure 5.2 34 level Figure 5.3 Modified layout for dredging 36 Figure 6.1 Final layout recommended by CWPRS 39 Figure 6.2 Locations of dumping sites off Mumbai harbour 41 Final Alignment of extension of navigational Figure 6.3 42 channel recommended by CWPRS Final Report Page i Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai LIST OF TABLES No. PARTICULARS Pg. No. Table 2.1 Tidal Levels 8 Tidal ranges at MbPT, Ambuja, Vashi and Rewas Table 3.1 13 Locations Comparison of Tidal ranges during non-monsoon Table 3.2 17 and monsoon Period Comparison of Ebb current during non-monsoon & Table 3.3 17 monsoon period at location C1 Comparison of Flood current during non-monsoon Table 3.4 18 and monsoon period at location C1 Comparison of Ebb current during non-monsoon & Table 3.5 18 monsoon period at location C2 Comparison of Flood current during non-monsoon Table 3.6 18 & monsoon period at location C2 Comparison of Ebb current during non-monsoon & Table 3.7 19 monsoon period at location C3 Comparison of Flood current during non-monsoon Table 3.8 19 and monsoon period at location C3 Summary of Co-Ordinates and Depth of Bore Table 3.9 21 Holes Table 5.1 Cost Estimate for Capital Dredging 37 Final Report Page i Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai LIST OF ANNEXURES No. PARTICULARS Annexure I Hydrographic Survey Report Annexure II Field Data Collection for Monsoon Season Annexure III Field Data Collection for Non Monsoon Season Annexure IV Geotechnical Survey Report Annexure V Mathematical Model Studies for Hydrodynamics and Siltation Mathematical Model Studies for Wave Transformation and Annexure VI Assessment of Wave Conditions Desk studies for Design of Proposed Extension of Navigational Annexure VII Channel Mathematical Model Studies to Assess Feasibility of Flood Annexure VIII Dumping Ground for the Disposal of Dredged Material Annexure IX Seismic Sub Bottom Profiling Studies Annexure X Seismic Bottom Profiling Studies (For Additional Work) Annexure XI Geotechnical Survey Report (For Additional Work) Final Report Page i Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai EXECUTIVE SUMMARY Mazagon Dock Shipbuilders Limited (MDL) is a premier leading warship building and offshore fabrication yard in India under Ministry of Defence, Government of India with ISO 9001:2008 certificate. The yard is currently engaged in prestigious projects both for Indian Navy and for export market. Also, company’s present portfolio of designs spans a wide range of products for both domestic and overseas clients. The MDL is situated on the leeside of Salsette/Mumbai Island on the west coast of India in the state of Maharashtra as shown in the fig. The location of MDL is at Latitude 18° 57’ 58” N and Longitude 72° 51’ 00” E in the Mumbai harbour area. Presently, MDL is building several frontline warships for the Indian Navy. The ships being constructed at MDL are required to be taken out of MDL area, for sea trials, to the open ocean and also towards the Naval Dock (ND) for fitting of weapon sensors. Since sufficient depths are not available in front of their waterfront and existing channel up to Offshore Container Terminal (OCT) of Mumbai Port Trust (MbPT), MDL is now dependent on the tidal window for their activities. The water depth available in these stretches is about 1.5 m to 2.0 m below chart datum (CD) and 6.0 m to 6.5 m during a tide of 4.5m. The maximum draft of fully fitted warships proposed to be built at MDL would be about 7.2m. Final Report Page i Feasibility Studies for the Proposed Extension of Navigational Channel at Mazagaon Dock, Mumbai In view of limited depths available near the MDL waterfront even during high tide level prevailing in Mumbai harbour, MDL intends to create a well demarcated navigational channel from MDL waterfront up to OCT, Mumbai with sufficient depth for smooth plying. In this regard, MDL had approached WAPCOS Ltd and CWPRS to undertake various studies for deepening and extension of existing navigational channel from northern waterfront of MDL to OCT MbPT berth. MDL entrusted CWPRS to carry out mathematical model studies to find out the feasibility of a new deepened / extended channel from their waterfront to OCT berth. In order to carry out the model studies field data pertaining to various hydrographic and oceanographic parameters were required and subsequently MDL had appointed M/s WAPCOS Limited to carry out field data collections (tides, currents, water samples, bed samples and geotechnical investigation) and to prepare Project feasibility report based on the model studies carried out by CWPRS along with quantum of capital dredging and cost estimate of the project. Accordingly, field data were collected and the reports on Non monsoon season data and Monsoon season data collections were submitted to MDL on June and November 2015 respectively. These field data along with past dredging data in the existing channel formed the inputs for the following studies carried out at CWPRS, Pune. 1. Mathematical model studies for hydrodynamics and siltation for the proposed extension of navigational channel. 2. Wave transformation studies to determine wave conditions. 3. Dispersion study to assess feasibility of flood dumping ground for disposal of dredged material. 4. Desk studies for design of proposed extension of navigational channel.