What Is Dredging?

What is Dredging?

Sand, debris and silt gradually fill the channels, harbors and waterways of various of bodies of water, raising the bed. This makes it difficult for ships, passenger boats and large vessels to pass through the waterways safely. Dredging is the process of removing debris and sediments that naturally gather on the bottom of bodies of water, making it easier and much safer for the waterways to be navigated.

Different types of Dredging

There are various types of dredging that each have specific goals. For example, environmental dredging, which aims to reduce and prevent expose of contaminants to people and wildlife. Flood prevention, oyster dredging and beach restoration are also other common types of dredging. However, for the purpose of this project, capital and maintenance dredging are the types that are being referenced.

Capital dredging: The initial excavation project to create a new port and deepen or widen a channel, usually to allow larger ships to travel through, with the goal of increasing trade of goods and enhancing the economy.

Maintenance dredging: The process of maintaining the work that has already occurred due to capital dredging. Increasing the depth of the waterway, removing debris/sediments and ensuring safety. This is the most common type of dredging.

Machinery Used

Trailing Suction Hopper Dredger: Suctions up sand and debris through a large pipe. Debris is held onboard the ship and then dumped at an off-site location. This is one of the most common types of machinery used for capital and maintenance dredging.

Cutter Suction Dredger: Also commonly used for capital and maintenance dredging, this piece of machinery uses a rotating cutter head to loosen the hard ground and difficult sediments that need to be broken up