The St Ola was a lot faster than I remembered. There was a good reason for this - in the 11 years since my last visit this far north, the St Ola had been replaced by a similar but much quicker vessel. The trip across the Pentland Firth to Stromness, Orkney now takes only two hours.
I finished my pint in the ships bar and went to the starboard viewing rail to watch the sunlight reflecting off that famous sea stack, the Old Man Of Hoy. Rafts of puffins and guillemots bobbed on the glassy surface of the water, and I decided to stay here until we passed the bows of the Inverlane.
This old oil tanker once rose 12m out of the waters of Burra Sound. I remembered standing on the very tip of its bow, looking down at the surface water boiling around it. I had heard rumours that the wreck had disappeared, and was able to confirm this with my own eyes as we sailed past the spot.
Only an unrecognisable metre or so of twisted hulk remained visible above sea level. Charter boats no longer tie up alongside this once-popular wreck.
My thoughts turned to the wrecks of the German High Seas Fleet that I would soon be exploring. I wondered if they were faring any better than the Inverlane in their harsh environment.
As we docked at the new ferry terminal in Stromness, I noted a few changes to the town. There was a dive shop in the high street and 20 dive charter boats in the harbour waiting for their guests to alight from the ferry. The place was a lot busier than I remembered; there have probably never been so many boats in the area since the Vikings moored their sleek longboats here.

Barrel of Butter
Our charter boat, the Three Sisters, left the pier at St Margarets Hope at 9am sharp. The weather was fine, which was a first for me up in Orkney. Soon I was remembering landmarks. The Isle of Flotta and its oil terminal came into view, and dozens of supertankers appeared like apparitions, only to disappear again as we steamed through intermittent banks of fog.
The Barrel of Butter was the next landmark I recognised. From weeks of poring over charts and diagrams of the area, I knew we would soon arrive at the resting place of the Dresden, the site of our first dive in Scapa Flow.
The Dresden was never one of my favourites but today conditions were good. Bright green water surrounded her bows and the two gaping holes once occupied by her forward gun turrets. The wreck lies on its port side, the only one of the light cruisers in this position, so we finned to the right along the now-vertical deck, taking in the sights.
On the shallow side of the bridge we found the C gun turret, its barrel pointed slightly down towards the deck. After a look at the breech end, we examined the remains of the bridge and swam further aft to the damaged areas around the engine room, where the salvors had blasted the hull.
There were many cogs and other machinery to view. My impression was that the Dresden had changed for the better. It has a lot to offer, and that intact bow is something not all light cruisers can now boast.
It was a positive start, and my spirits soared. That this wreck had not deteriorated was promising. It wasnt long, however, before my hopes were dashed. From the glorious sunlit deck of the Three Sisters, we descended through the green water for an afternoon dive on a complete pile of scrap that was once the Karlsruhe.
From my previous trip I recalled intact bows and stern, but the already completely broken midship area seemed to have enlarged in the intervening years.
It was not until I reached the armoured control tower, with its open rear door and narrow viewing slits through which green light filtered, that I knew I was near the bow. The hull reforms here to some extent, but both forward guns have slid to the sea floor to lie together.
Capstans and winches are still in place, minus most of the deck, and the hawse pipes now also lie on the sea floor, the anchor chains still running through them. The pointed bow has also broken away. One of my favourite sites in the Flow now lies broken on the seabed.
The Karlsruhe, the shallowest of the main German wrecks at 26m, is still an enjoyable dive. Visiting in August, I found the fish life to be prolific on this and all the other wrecks. The Karlsruhe drew gangs of large pollack, lurking in the shadows of the piles of broken plates. The wreck was surrounded by vast schools of juvenile whiting.

Life at depth
At the other extreme in terms of depth is the Markgraf, the deepest of the High Seas Fleet at 45m, but surprisingly this was even more densely covered in orange and white dead mens fingers, while schools of juvenile fish swarmed around its massive bulk.
I was impressed by this wreck. Like that other battleship in the Flow, Kronprinz Wilhelm, it is huge and generally intact, although upside-down.
Trying to find the side armament on both these ships proved fruitless. I knew that I was in the general area, but they are so immense that I failed to spy them. On ascending from the Kronprinz Wilhelm, passing all the broken armoured plates lying at odd angles on the hull, I shuddered involuntarily on realising that I had been swimming beneath the upturned deck and that most of the hull above was broken and insecure-looking.
We stayed shallow on the third battleship wreck, the König, which lies in 40m. Its inverted hull is almost completely broken, and the remains rise more than 20m, with brass cooling turbines littering the area around the engine rooms.
Most of this damage on all three battleships has occurred in salvage attempts and generally I was pleased with the condition of the wrecks. You need to do a number of dives to cover them comprehensively but the consensus of opinion among the other divers in the group supported my own.
The cruiser Brummer had been, in my opinion, the best wreck in Scapa Flow, and I eagerly awaited the opportunity to get down the shotline and reacquaint myself with it. At first, everything was fine. I viewed the gun on the centreline at the rear of the bridge area though, finning over the bridge area, I did think it looked a little less intact than I remembered.
As I moved forward, I noticed some areas where the armoured deck was peeling away from the hull. The bow gun was still there in pristine condition, surrounded by capstans and winches.
We decided to swim forward to inspect what I remembered as the beautifully curved prow of this sleek ship. I was enjoying myself but, as we neared where the bow should have been, the hull curved down sharply and it proved to have disappeared.

I couldnt believe it. The Karlsruhe was one thing - but the Brummer! We didnt descend to see how bad the damage was, but in the 10m viz I saw no sign of the bow reforming.
I surfaced, my previous appreciation of the wreck somewhat dulled. The Brummer had been the favourite of many divers in the Flow. What had caused the bow to break off - 80 years immersed in a cold sea The weather Damage caused during the scuttling which weakened its structure Or are we divers part of the cause
As diving equipment has evolved, we can enjoy longer bottom times on the wrecks, during which we vent gas from our open-circuit systems. It becomes trapped in compartments, bringing to bear forces which the vessel was not designed to counter.
Keith Thomson, skipper of the Three Sisters, holds firmly that oxygen-rich nitrox fills are speeding up the corrosion and deterioration of the wrecks.
My view is that all the above factors contribute. Diving in the area has increased five times over during the past decade - in returning to Scapa Flow I had become part of the problem.

Create a diversion
What can be done to stop the rot Dive-boat operators have been discussing the problem and now a feasibility study by Orkney Harbours has started to examine the pros and cons of sinking more wrecks in the Flow, to help protect the High Seas Fleet by diverting the attention of some of us visiting divers.
If the trawler James Barrie is anything to go by, even wrecks of no standing in naval maritime history could prove a huge success, especially if sunk in the clear waters of the more tidal sounds.
The James Barrie is intact - apart from its brass portholes, of course. Valves have also been ripped off in the engine room, and if you venture in here your drysuit will be a lot blacker when you exit because of the previously trapped oil that has leaked from where missing gauges should be.
What I enjoyed most about this wreck was that, 20m down, the entire shape of the trawler could be discerned in the 20m viz. At 666 tons, the James Barrie is not small. It lies on its starboard side, with the deck rising some 7m off the seabed and its handrails silhouetted in the bright green water.
The wheelhouse is an interesting spot, with fish swimming in and out of the windows. Further aft, the funnel can still be viewed along with all the other non-brass deck fittings. We enjoyed this wreck so much, we decided to do it again the next day.
Two dives on a trawler when we could have been overdosing on the High Seas Fleet Absolutely!

Its number one
After the disappointment of the Brummer, another fantastic wreck awaited to brighten my spirits. The Tabarka is a blockship in Burra Sound, lying in around 12m of fiercely tidal water. It is completely inverted, but that doesnt matter, because you need to dive within the hull unless you wish to be swept away.
The Tabarka went straight in at number one among my favourite dives, at least in part due to the bright, clear conditions and colourful marine life. You dont have to be in shallow water in Scapa Flow to enjoy such conditions, but it helps.
As I learned later, the Tabarka has won plenty of fans. It is intact, so there isnt always a clear exit to the surface, but the spaces inside the wreck are huge and open and the viz amazing.
The ships engines are there to be seen, though upside-down, and the three large boilers make good photographic props. They have fallen to the sea floor and are covered in soft corals, as is most of the wreck.
Sheltered within sections of the wreck, you can look outside to watch immense schools of pollack swarming about in the strong currents.
Our week of glorious weather in Scapa Flow was almost at an end. The viz had dropped to a gloomier 6m, but for our last dive the Köln remained a tremendous prospect. Still much as I remembered it, this wreck has now replaced the Brummer as the best-preserved light cruiser.
Champagne bottles were uncovered from the sea floor around the stern. Further up the now vertical deck, two 6in guns were mounted on the centreline, their muzzles still pointing aft. A piece of the leather bung which plugged one of these was still there, though the design I had seen on it the last time had disappeared.
Once past the disorientating 10m gap where the salvors have blasted this ship apart, the hull reformed and a smaller high-elevation gun could be seen. Bunkers full of coal lay beside huge holes where the funnels once belched black smoke. Stairs descended to the deck below but were blocked by sediment.
So I arrived at the most impressive sight yet offered by the German wrecks of Scapa. Passing over the foremast and finning along the bridge area, I saw the outline of the twin-level circular control towers, the upper level adorned with a T-shaped structure - the central gun control rangefinder. This was the fighting heart of the ship, from where its guns would be trained and the orders given to fire.
You get used to seeing big gun turrets, large capstans and so on in Scapa Flow, but the Kölns bridge and fighting control towers gave me a real sense of the scale of these vessels and an insight into how they worked.
You dont get that from looking at a grainy black and white picture, but will that be all we have left in a few years time

Preservation first
The German High Seas Fleet wrecks still provide a diving experience unparalleled in Europe. The Brummer and the Karlsruhe are showing scars but both still provide excellent dives. I only hope the people of Orkney can find a way of saving these wrecks from further damage.
The Orkney Islands Council is now advertising only charter boats that are members of the Dive Boat Association, which means vessels that surpass Marine Safety Agency regulations.
The objective is to ensure a high standard of safety afloat on the Flow and marks the first stage in protecting its historical wrecks by allowing access only to those operators who are felt to put preservation before profit. Check that your chosen vessel is a member of the DBA.

The first 3D maps of the military wrecks in Scapa Flow have been made with the help of innovative marine survey equipment. Oil technologists and hydrographic surveyors carried out a wide-scan sweep of the Flow using a Kongsberg Simrad portable multi-beam


GETTING THERE Go as far north as you can using the A9 from Thurso. From here go to Scrabster to sail to mainland Orkney. There are secure car parks in Scrabster, which cost around£12. The ferry crossing costs£35. Flights are also available from the UK to Kirkwall airport on Orkney.
DIVING: There are vessels in Scapa Flow to suit every pocket, ranging from£120 for a week to£400 for those who prefer the liveaboard option. Mike Clark dived from the Three Sisters (Keith Thomson, 01856 831372). Total cost of his boat diving and accommodation for the week was£250. Make sure that the dive boat you choose belongs to the Dive Boat Association.
WHEN TO GO: Diving can take place all year round because of the sheltered waters but is best from May to September. Plankton blooms can reduce viz in May and June but depend on the weather - check with your skipper.
ACCOMMODATION: There are many hotels, B&Bs and youth hostels as well as liveaboards. Most land-based accommodation is found in Stromness, where the St Ola docks on arrival. Mike Clark stayed at the Sands Motel on Buray, which was handy for the short drive to St Margarets to meet the Three Sisters.
FURTHER INFORMATION: Orkney Tourist Board 01856 850716, www.orkney.com