PIANC, the World Association for Waterborne Transport Infrastructure, has just released a document produced by Wessex Archaeology’s Coastal & Marine team, with contributions from authors around the world, which provides advice and guidance on how to protect archaeology during dredging and port construction following a workshop in Brussels in November 2012.
Evidence for our heritage offshore ranges from Palaeolithic stone tools and the remains of megafauna, to downed aircraft and boats, ships and the flotsam and jetsam that come with them. 
PIANC’s new guidance promotes best practice when planning and implementing commercial schemes that may affect archaeological material or features. From assessing the local context of projects and the potential impacts on heritage, to collecting data about known or suspected sites and then applying mitigation and protective measures, ‘Dredging and Port Construction: Interactions with Features of Archaeological or Heritage Interest’ provides a valuable and much-needed framework for development schemes.
The guidance is available to download free of charge from PIANC’s technical report download library - http://www.pianc.org/technicalreportsbrowseall.php