The Guide is intended to give future Owners the information they need to consider a Submerged Floating Tunnel (SFT) as a realistic, safe, economic alternative to
bridges and conventional tunnels for crossing waterways, including terms and definitions, general requirements, design, construction, operation, inspection and
maintenance.

As no SFT has yet been built, the guide draws on the knowledge and experience of Owners, researchers and project engineers who have been involved in feasibility
studies, planning and designing of SFT concepts. All technical solutions discussed herein are based on ideas that have been put forward in previous studies, and these studies are listed at the end of the document.

A large body of knowledge and experience exists from projects such as immersed tunnel (IMT) structures and offshore structures, and from tethers, moorings and
anchors used in the oil & gas and renewable energy industries; these can assist the development of SFTs. Indeed, SFTs incorporate technology from both IMTs and offshore structures. However, the combination of technologies within an SFT is yet to be proven at full scale.

The Guide would aim at a twofold objective: to provide a brief guide for deciding when an SFT is an appropriate option for a permanent water crossing and to
address the issue for understanding what being the Owner of an SFT entails. To keep the guide concise, undue discussion of topics that are not SFT-specific have
been avoided to the extent possible.
As this is not a design guide, technical discussions are kept at a descriptive level. The reader is encouraged to consult the references for details.