Dredging is a common, well understood and tightly regulated activity and has been taking place in coastal areas alongside the GBR for many decades.
Dredging is critical to the maintenance and development of port infrastructure. It involves the removal of seafloor material (mainly sand and silt) to allow enough room for ships to enter a port safely.
Extensive investigations are required to ensure the characteristics of the dredge materials and any potential impacts arising from its removal are well understood and managed long before an approval is granted.
Collected material is either relocated to similar areas on the sea floor, or may be used in land reclamation activities. Sea-floor relocation sites are carefully selected well away from existing habitats and corals and the distribution of any relocated materials is closely monitored.
For further facts on the mining industry activities, dredging and the Great Barrier Reef, please visit:
Queensland Government Reef Facts: http://www.reeffacts.qld.gov.au/
Queensland Resources Council GBR Fact Sheets: https://www.qrc.org.au/01_cms/details.asp?ID=3284