What Does Construction Site Dredging Entail?

Posted on: 11 August 2020


Few types of work on a build are as highly specialized as construction site dredging. This is a process where excavation is conducted in submerged areas, usually in advance of installing marine structures like piers, docks, levies, channels, or even foundations for buildings adjacent to the water. If you're planning to bring in a contractor to handle this sort of job, it's wise to learn about what it entails.

Equipment and Processes

Companies can send boats to most locations along coasts and rivers to perform constructing site dredging work. Some contractors also are willing to haul equipment to inland bodies of water.

The main tool is a machine called a dredge. This is usually attached to a crane of some type, and an operator will lower the dredge into the water to scoop out sediment. The sediment is then placed on board the ship or at a site along the shore to be hauled away or reused.

Dredges come in four varieties that fall into two main categories. Hydraulic and suction dredges create a mixture of mud and water that's then sucked up from the bottom of the waterway. These models are ideal in circumstances that are difficult, such as choppy waters. Hopper and mechanical dredges scoop the sediment up from the bottom, and they're usually ideal for situations where high precision is necessary.

Pumps are also used if the area to be dredged needs to be dry for construction work to commence. Temporary barriers can be installed to keep the location dry while dredging and construction moved ahead. Once the job is finished, the barriers are removed and water will flow to the new structure.

Required Skills

Underwater topology is a tricky business to deal with, even with modern devices. Professionals have to identify the correct site for dredging, and they also have to handle the job in a way that passes muster with regulatory authorities. For these jobs, applicable regulations usually cover worksite safety, water quality, and waterway traffic. Simply put, construction site dredging people have to be excellent at not making a mess while operating in potentially difficult conditions.


As with most construction projects, ones that involve dredging tend to call for a lot of permits. Especially with waterways that connect elsewhere, you can expect the local, state, and federal regulators to all have questions about the impact dredging might have. You should have a full engineering study in place before seeking permits so you can answer these questions with authority.