India is primarily a maritime country.
It is the seventh-largest country by area, the second-most populous country (with over 1.2 billion people), and the most populous democracy in the world. India projects into and is bounded by the Indian Ocean –- in particular, by the Arabian Sea on the southwest, the Lakshadweep Sea to the south, and the Bay of Bengal on the southeast.
In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives towards the West and the South. India’s Andaman and Nicobar Islands share a maritime border with Thailand and Indonesia and are very close to SE Asia. The Lakshadweep Islands lie 200 to 300 km (120 to 190 mi) off the coast of Kerala in the Arabian sea with an area of 32 km2 (12 sq mi). They consist of twelve atolls, three reefs, and five submerged banks, with a total of about 35 islands and islets. The Andaman and Nicobar Islands consist of 572 isles, lying in the Bay of Bengal near the Burmese coast.
The major Sea Lanes Of Communications (SLOCS) pass within the vicinity of the Indian Peninsula.
India’s coastline measures 7,517 kilometres (4,700 mi) in length; of this distance, 5,423 kilometres (3,400 mi) belong to peninsular India and 2,094 kilometres (1,300 mi) to the Andaman, Nicobar, and Lakshadweep island chains. 12 major and 200 non- major ports are dotted along her coast.
According to the Indian naval hydrographic charts, the mainland coastline consists of the following: 43% sandy beaches; 11% rocky shores, including cliffs; and 46% mudflats or marshy shores.
India is one of the world’s fastest-growing economies. The Indian maritime industry is an integral part of the country’s trade and commerce. It supports 90% of India’s trade by volume.
India’s has a potentially navigable waterways of 14,500 kms.
The National Waterways (NWs) Act 2016 to promote inland waterways for trade came into effect on April 12, 2016. It has declared 106 new waterways as NWs, in addition to the five existing NWs notified earlier. After the Techno Economic Feasibility (TEF) study and Detailed Project Report (DPR) commissioned on each of the NWs, 37 NWs are planned be taken up for development in the coming years by Inland Waterways Authority of India (IWAI). Work has been awarded for 5 NWs and tendering for award of projects on the remaining 32 NWs is to be undertaken shortly.
As India continues to grow economically, it will have to leverage its unique geographical, riverine and maritime position and assets to access the world for trade (the movement of goods) and the most cost effective distribution of resources among its populace.
As will be seen, development of inland waterways, its coastline and ports will be crucial. And for that dredging will play a very important part in the decades to come.
Capital and Maintenance Dredging
Dredging is an excavation activity usually carried out underwater, in shallow waters – coastal areas, shallow seas, back waters, rivers, lakes, reservoirs, etc – with the purpose of gathering up bottom sediments and widening.
Dredging is carried out to control the effects of erosion and deposition which are continuous phenomenons – for improving navigability and capacity, making waterways navigable, renewing loss of material or land due to erosion.
Dredging is an important activity and a requirement in today’s world.
River Management & Flood Prevention
River management or engineering is the process of planned human intervention in the course, characteristics, or flow of a river with the intention of producing some defined benefit. People have intervened in the natural course and behaviour of rivers since before recorded history—to manage the water resources, to protect against flooding, or to make passage along or across rivers easier.
Floods are caused by many factors or a combination of any – generally prolonged heavy rainfall, (locally concentrated or throughout a catchment area), highly accelerated snowmelt, severe winds over water, unusual high tides, tsunamis, or failure of dams, levees, retention ponds, or other structures that retained the water. Flooding can be exacerbated by increased amounts of impervious surface or by other natural hazards such as wildfires, which reduce the supply of vegetation that can absorb rainfall.
Periodic floods occur on many rivers, forming a surrounding region known as the flood plain.
During times of rain, some of the water is retained in ponds or soil, some is absorbed by grass and vegetation, some evaporates, and the rest travels over the land as surface runoff. Floods occur when ponds, lakes, riverbeds, soil, and vegetation cannot absorb all the water. Water then runs off the land in quantities that cannot be carried within stream channels or retained in natural ponds, lakes, and man-made reservoirs. About 30 percent of all precipitation becomes runoff[1] and that amount might be increased by water from melting snow. River flooding is often caused by heavy rain, sometimes increased by melting snow. A flood that rises rapidly, with little or no warning, is called a flash flood. Flash floods usually result from intense rainfall over a relatively small area, or if the area was already saturated from previous precipitation.
Flood control methods are used to reduce or prevent the detrimental effects of flood waters. Flood relief methods are used to reduce the effects of flood waters or high water levels.
Channellisation, canalisation, regulation of flow, estuarine works, dams, floodplains and ground water replenishment, river and coastal defences, barriers, etc are often the techniques adopted for management of rivers.
WE brings world class capabilities and techniques towards management of rivers and prevention of floods.
Wetland Management
A wetland is a land area that is saturated with water, either permanently or seasonally, such that it takes on the characteristics of a distinct ecosystem.[2] The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil.
Wetlands are also considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life and are critical for the good health of the environment.
Wetlands play a number of roles in the environment, principally water purification, flood control, carbon sink and shoreline stability.
Shoreline Stability
Over the last two decades, biogeomorphology has developed as an established research field examining the interrelationship between organisms and geomorphic processes in a variety of environments, both aquatic, and terrestrial (Naylor, Larissa A. 2005). Shoreline biogeomorphology looks at the interaction between aquatic organisms, and shore based geomorphic processes.
This includes not only microorganisms and plants, but animals as well. These interactions are very important factors in the development of certain environments like marshes, wetlands, and other types of coastal wetlands as well as influencing coastal and shoreline stability as well as flood control.
