It’s the start to an exciting week ahead as I’ll be working underwater! It’s a diving fieldwork which generally takes a couple of months of planning to organised and the go ahead to proceed has been given by the Project Manager – with the right tidal window and ideal weather conditions forecasted, we’re keeping our fingers crossed hoping this lasts the whole duration of the project!
Mobilisation on the first day is generally a long day, with an early start travelling to the harbour where our diving vessel would be docked. Upon arrival the diving team, usually consisting of a Diving Supervisor (DS), Project Office (diver), and two other diving team members, receive a site/safety induction from the DS and vessel master, and then start unloading the diving kit and storing this onboard the vessel. Housekeeping is crucial; we’re generally working in a small space with a minimum of five people and therefore to maximise space and make sure equipment is safely stowed, this is stored in big crates and tucked beneath benches or within the cabin. Once this is all complete, we’re pretty much sorted for diving to commence.
Over the next few days, we head out to sea depending on tide times – early mornings or afternoons – no diving is done at night. First task is to set up the diving kits for each diver, consisting of a primary tank and bailout, buoyancy control device (BCD), regulators (delivering breathing air from the tank to the diver), knife, diving computer, fins and other equipment (depending on the task of the day). Divers get dressed into their dry-suit - fingers crossed no leaks! - and a tender helps the diver kit in. A buddy system is used when we undertake SCUBA operations, allowing the buddy pair to freely swim on site. Once the divers are kitted, diver checks done, and full-face mask donned, they’re ready to jump in the water!
The first dive is generally a reconnaissance dive - locating the site and observing (when visibility allows) current condition of the site, whether it’s a scatter of artefacts, a wreck site or even an aircraft crash site. This helps plan out the rest of the diving week and feeds back any unforeseen risks or setbacks. SCUBA dives may last up to 1 hour, depending on exertion spent doing a task. These vary from clearing the site from marine growth, taking scaled photographs, mapping the site by means of annotated sketches with measurements, taking photographs to produce orthographs or photogrammetry models of the site or artefacts, and cataloguing any finds. Watertight cases and camera housing keep equipment dry and safe from water damage. Weights not only aid divers descend easier but also help avoid scales from floating back up!
Whilst divers are underwater carrying out a task, a tender or standby diver onboard the vessel keeps track of the divers by keeping an eye out for surface bubbles and notifies the DS of any divers on the surface. Once the dive is complete, divers return to the vessel and get a lift (literally as diving vessel are equipped with dive lifts to make it easier to get back onboard) back on the vessel. A steaming cup of tea is a must as part of de-kitting, with a quick debrief and assigning tasks to the following buddy divers.
Back ashore, at the end of a diving day, equipment is organised and made ready for the following day. Any data collected is downloaded, checked, and processed to make sure there are no data gaps. As the work is underwater, we are sometimes restricted by visibility, water conditions, weather, site accessibility etc., therefore, we make the most of the time we are given and obtain as much good quality data as possible, as we do not always have the opportunity to re-visit the site.
At the end of the diving fieldwork, hoping that all our objectives were met, demobilisation is undertaken. Back at the office, the data collected on site is utilised to form the basis of the report which is then submitted to the client or archaeological curator. The work rarely ends here depending on whether, for example, the work was undertaken as part of a larger marine development or as part of our contract with Historic England or Historic Environment Scotland.
The former generally would entail a site assessment, with a method statement having been approved by the national archaeological curator, to decide next steps and mitigate against impacts to the site, whether by recording/preserving in situ or lifting off the seabed. This would entail discussions between the client, developer, national archaeological curator, and the archaeologists undertaking the work. Often micro-siting is achievable, and sites/material are preserved in situ. However, there are instances where this is not possible and therefore excavation/lifting of material is the only way forward, leading to further avenues of work.
