A dredge is defined as an apparatus used for an excavation activity that is carried out at least partially or fully submerged underwater, with the purpose of gathering up bottom sediments and disposing of them at a different location.
DSC specializes in hydraulic dredges. Essentially, a hydraulic dredge functions like a floating vacuum, excavating and pumping material through a pipeline to a different location using a centrifugal pump. Hydraulic dredging is the cleanest, most precise and environmentally friendly method of dredging today.
Alternatively, mechanical dredges are used for removing debris or hardened material that is tightly compacted, using buckets to dig and transport material to different locations. Mechanical dredges do not typically retain fine materials as well as hydraulic dredges.
What is Dredging?
Dredging is an excavation activity in which materials are recovered from beneath the water's surface. The purpose of dredging is generally to gather bottom sediment and either dispose it at a different location or use these sediments in various products. For example, sand and gravel are used in concrete mixtures. There are many uses for dredges, all of which vary and require different types of dredging equipment. Below are some application examples, with some suggestions for dredge selections.
Dredges can be used during construction projects that require the creation of trenches for pipelines and tunnels, and in the forming of foundations for structures. Dredging is also used at the onset of a project to help create land, remove land, create channels, create harbors/marinas and for various other construction needs. Depending on the project requirements, DSC has many dredge options available to meet the rigorous demands of construction projects.
Dredges are often used to clean contaminated areas and restore those areas to non-contaminated levels. Hydraulic transfer of contaminated sediments has become known as the most cost-effective and efficient way to restore contaminated sites. DSC offers a wide range of environmental dredges, ranging from the 8-inch Moray Class Swinging Ladder dredge, to the Wolverine or Badger Class, to custom-designed dredges and workboats.
Dredging is as an efficient means to excavate sand, gravel, precious metals, coal, phosphates and various other minerals that are mined and added to materials we use every day. Most mining dredges require higher levels of throughput, and must be designed for the rugged demands of the materials being dredged. We recommend our Marlin and Shark Class dredges for mining applications as they are capable of digging deeper and pumping farther.
Dredges can be used to deepen channels and waterways as a means to improve navigation. Navigational dredging is most commonly used in ports, harbors and shipping channels as a way to maintain these waterways so that large ships, oil tankers, container ships, barges and naval vessels can pass. Maintenance dredging is required periodically to remove sediment, and is a necessity for almost every navigable waterway and port. We recommend our Shark and Barracuda Class dredges for most navigational projects because of their compact size and their maneuverability.
Dredges can be used to maintain, expand and deepen lakes that have progressively become shallow from deposits and overgrown vegetation. If lakes are not dredged periodically, they become too shallow for boats and swimmers to enjoy them. We recommend our Barracuda, Moray, Wolverine or Badger Class dredges for these projects, as they are small and can be easily maneuvered in tight areas. The Barracuda and Moray dredges, in particular, feature a swinging ladder configuration, so the dredge can work without external swing wires or anchors.
Dredges are often used to restore wetlands, beaches, lakes, streams, coastlines, and for other land reclamation projects. In many coastal areas there is a shortage of land for development, therefore, dredges are used to pump material ashore and create new land or restore eroded material. Various dredge types can be used for restoration dredging depending on the project requirements. DSC’s Shark, Barracuda, Wolverine, Badger and Amphibious Class dredges lend themselves well to restoration dredging projects due to their highly portable design and maneuverability.
Sometimes dredges are required for projects so specific they do not fall into any of the categories listed above. In this case, DSC engineers can work with your team to design a dredge that will incorporate your specific requirements. Whether a project calls for extreme dredging depths, high excavation forces, long discharge distances or whatever challenges you may face, we can custom design a dredge to meet your project demands.