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Underwater mines and quarries are one of Finland's specialties, what it comes to recreational diving. These mines have been filled with clear groundwater after the mining operations have come to an end. Visibility in these mines is often excellent, compared to uncertain conditions in the natural archipelago and lakes. Indeed, the visibility, the dramatic scenery of the tunnels, and the easy and safe travel to the dive site make the mines very popular, not only among recreational divers, but also as training sites.


However, mines can be like labyrinths and often require complex navigation and special training to be dived safely. This in turn requires experience, knowledge, and careful planning. Two-dimensional maps of the mines exist, outlining the routes marked with guide lines. These maps are often difficult to read and require previous diving experience in the particular mine, especially if the mine has multiple levels. Understanding the three-dimensional nature of the mines, i.e. the connections between different layers, distances, and depths can be difficult using two-dimensional maps. Additionally, many navigational signs, restrictions, and visual details are also often completely ignored. All of this, of course, can jeopardize diver safety, and make mine diving unattractive.



Our planned 3D photogrammetry documentation project has two goals:


1) Increasing diver safety

We believe that three-dimensional and realistic maps of the mines would make dive training even better and safer, improve diver safety, assist in dive planning, facilitate the fixing of guide lines, and assist in any search, rescue or recovery operations. We hope these 3D models would benefit both recreational divers and professional divers.


2) Preservation of cultural and historical information

Our second goal is that by documenting the mines, we could preserve cultural and historical information, and bring this history and the most interesting details available to anyone interested in the topic. The aim is to make the 3D photogrammetry models as freely available to everyone as possible, and to open a virtual museum where the 3D models could be permanently stored.


The project will be run by Bottomline Projects and their partners. The diving phase of the project will begin in the summer of 2021 at the Kaatiala mine and quarry in Kuortane. The next step is to build the 3D-model using photogrammetry. The end result is a virtual replica of the underwater mine, revealing even the smallest details. This virtual mine can be "stepped in" from any mobile or desktop device.

After the initial pilot project in Kaatiala, our ambitious goal is no more, no less, than to create a 3D photogrammetry model of every single underwater mine system in Finland. For this, we are hoping to work together with many of the highly skilled local divers and other professionals we have in Finland. Otherwise this will keep us busy for the next 30 years.....

Project "Finland Underground" and its Kaatiala chapter is moving forward at a steady pace. One of our main methods is 3D-photogrammetry, which is not a new way of creating 3D-models, but when done underwater and in an overhead environment, it has its own challenges and becomes a totally new territory of scientific exploration. In a nutshell, photogrammetry means taking hundreds, or in our case, hundreds of thousands of photos and then running them through a software that overlays them and while doing so, creates a three dimensional photographic model of the object. Sounds simple, and it is, if you are modelling a car on a parking lot. But try a cave system under water which is connected to a lake and a forest at the surface and you will encounter a few question marks on the way Here are a couple of details from the Kaatiala mine. The final massive combination of a model that includes all elements is forming up nicely, but is still too early to be revealed To give you a little idea of what to expect, you can view the 3D examples by clicking the link under each photo.


All picture rights belong  to Bottomline Projects

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