In recent times, the drastic change in climatic conditions has moved the Indian government to focus on sustainable and efficient infrastructure development. To mitigate any potential impact on the environment and secure the marine ecosystem, the Ministry of Ports, Shipping and Waterways (MoPSW) is promoting the uptake of sustainable dredging practices, reuse of dredged materials and better monitoring systems and technologies. At a recent India Infrastructure conference, H.N. Aswath, Development Adviser (P), MoPSW shared his views on the potential of these sustainable practices, related initiatives being undertaken and the associated challenges in their implementation. Edited excerpts…
Sustainable dredging practices at Indian ports
During the past 10 years, MoPSW has been taking several steps to reduce the damaging effect of dredging on the marine ecosystem and abate carbon emissions from associated activities. It is taking careful measures in carrying out various dredging activities at its major and non-major ports. These measures include assessment of the kind of soil that would be excavated and dredged materials that can be recycled and reused. For instance, the significant task of maintenance dredging of around 22 million cubic metres (mcm) quantity has been made possible at its Cochin port with the application of three dredgers for around 12 to 14 hours per day and vessels of around 15 metres drop, without any problem. In this process, the port undertook the survey and geotechnical investigation annually and assessed the quantum of dredging required and the type of soil to be excavated. Further, the port also decided on the use of dredging material such as sand and silt upon its segregation, washing and adding some admixture. This material is being provided by the port to various construction agencies such as the Public Works Department.
Initiatives by MoPSW for increasing efficiency and sustainable practices
Various policies and guidelines have been formulated by MoPSW to ensure transparency and increase efficiency and sustainability. It launched the Dredging Guidelines for Major Ports in 2021, covering various aspects such as the standard operating procedures and project planning, including the preparation of detailed project reports, environmental code of practice and quality assurance plan the Guidelines also detail plans for the uptake of public-private partnership mode for dredging activities, and enlist a number of uses for dredged material such as land creation, beach protection, construction and possible reuse of by all the major ports.
Another milestone is the launch of the Sagar Samriddhi scheme, in line with the reuse of dredged material. It consists of two aspects, the reuse of dredged material and the use of an online dredging monitoring system. With respect to the reuse of dredged material, it emphasises the need to segregate any kind of soil mixture (clay, silt or sand) after bringing it to the shore. Necessary steps for its reuse must be taken instead of dumping it in the sea, affecting the marine flora and fauna. The other one is the assessment of dredging activities through an online dredging monitoring system. Any difficulties that lower the productivity of the dredging process can be monitored remotely with this system and proactive steps can be taken thereafter.
The ministry is also cautious of the tremendous carbon emissions caused by the movement of ships and dredgers and its harmful effects on the environment. As From traditional dredgers, some dredging companies are shifting towards eco-friendly fuel and have acquired LNG-based dredgers. Similarly, MoPSW is pushing for the indigenous manufacturing of dredgers. In line with this, Cochin Shipyard Limited, a leading shipyard company in India, will build sophisticated dredgers with assistance from Royal IHC Holland BV in the Netherlands. Royal IHC has also opened an office in Navi Mumbai, Maharashtra to allow ease of delivery of spare parts and other components of dredgers. Besides, Cochin Shipyard Limited will also deliver on the construction of 12,000 cubic metre capacity of dredgers by the end of 2025 and is being pushed to collaborate with foreign companies to develop LNG-based dredgers and inland dredgers.
Furthermore, the use of the right type of dredger is necessary to optimise dredging activity and its monitoring with the proper deployment of personnel. The Dredging Corporation of India has been assisting the inland waterways to this end. At present, the inland waterways function excellently, with around 105 million tonnes (mt) of cargo. There are around six National Waterways (NWs) successfully functioning in India. Of these, NW 1 covers a distance of around 1,640 km from Varanasi to Kolkata, while NW 2 covers river Brahmaputra for a distance of around 897 km.
In addition, MoPSW expects dredging companies and organisations such as Maharashtra Maritime Board, the Gujarat Maritime Board and to systematically structure their dredging projects, especially by conducting the environmental impact assessment study well before the start of the project.
Upcoming ports and associated dredging requirements
India is growing at a GDP growth rate of 7.2 per cent. At this pace, the underlying future requirement for EXIM cargo will be enormous, requiring the building of more ports in India. In response, MoPSW plans to develop two to three mega ports in the next three to four years. For instance, the foundation stone of Vadhavan Port in Maharashtra with around 20 million twenty-foot equivalent units (TEUs) capacity was laid recently. It is expected to be the biggest port in India and will require a huge amount of dredging. It will need annual maintenance dredging to the tune of around 10 million cubic meters.
Similarly, another big transshipment port is being planned in Galathea, Andaman and Nicobar Islands, which is around 1,000 km from the coastline. Around 4 million TEUs of capacity is planned for the initial stage, which will be ultimately increased to 8 million TEUs. It will also play a strategic role in transshipping cargo of the neighbouring countries such as Myanmar and Bangladesh, which currently depend on Singapore and Colombo for the same. This will reduce their cargo handling costs and subsequently help in improving their economy. However, as a greenfield port, it will pose many challenges for the dredging community. It is assessed that around 10 mcm of capital dredging and another 3 to 5 mcm of maintenance dredging will be required. A careful assessment study will be needed to address this quantum of activity.
Furthermore, several coastal state governments are also being assisted under the Sagarmala Programme for the establishment of fishing harbours and new terminals. Around 100 fishing harbours and around 25 to 30 roll-on/roll-off ports (ro-ro) are being developed. All these together will also increase dredging requirements.
The way forward
The current capacity of major and non-major ports of 2,500 million tonnes is planned to be increased to at least around 3,500 million tonnes in the next five years by MoPSW. The capacity is further expected to be augmented to 10,000 million tonnes by 2047 under the Maritime Amrit Kaal Vision 2047. As a result, dredging activities are expected to grow significantly. The main focus of the government will be on boosting the dredging capacity by increasing the number of dredgers. It will be necessary to ensure that dredging companies with an insufficient number of cutter suction dredgers are able take up capital dredging by assessing their requirements. The other important area for MoPSW will be the reuse of the dredged material. Of the 155 mcm of dredged material received at present, around 15-20 per cent should be reused instead of being dumped in the sea. Apart from preserving the environment, this will help in pumping the economy through recirculation of used materials. In support of this, a study by IIT Bombay, called “Dredging Material” has been initiated to discuss the mechanism for the use of dredged material.
Further, the monitoring of the dredging activity under the Sagar Samriddhi scheme will be an important area. The adoption of an online dredging monitoring system will help in reducing the inefficiency of the dredging process. Finally, complaints regarding delays in dredging projects would also need to be addressed and prevented.
In the coming years, around 106 NWs will be implemented in phases. By 2047, another 30 to 40 NWs are expected to become fully functional, which will require regular maintenance as well as capital dredging.