ScottBakula · Today 22:06
Tell us more
OK, I hope you don't regret asking...
There are oil, gas and other pipelines all over the seabed and the owners have them inspected regularly, for integrity. They don't want them damaged and leaking.
One of the big problems is freespans, unsupported lengths, with no sediment support underneath. This can cause them to sag and weaken. These can be caused by currents, or fish burrowing.
Debris can be problematic, as it can damage the pipes, or coatings. Metal debris can induce electric currents, which hasten corrosion and may need to be removed.
Another potential problem is dragging, which is caused by negligent dropping of anchors by ships, which drift, catch the pipes and pull them. Naughty fishermen ignoring exclusion zones also drag them and both can damage the anti-corrosion coatings.
We use geophysical tools to assess and map them. We also use ROVs, small submersibles, tethered with cables, which transmit data up to the ship. These have video cameras, along with multi beam echosounders (used to make 3-D maps of the seabed, sometimes geophysical tools, usually including trackers, high tech metal detectors, which can locate and map them beneath the sediments.
Then we produce maps, written reports and long, tedious spreadsheets.