Morskie Oko Lake

Many Polish divers have a dream to dive in Morskie Oko. It is a mountain lake in the Tatra Mountains at altitude of 1400 m a s l. Thanks to my colleagues from TOPR mountain rescue services, I was lucky to make a few-day diving expedition to explore it.

There are 2 ways to get to the Morskie Oko Lake – the first one is on foot, and the second one by a TOPR 4x4 car; I selected the second option, especially that I had my O2ptima rebreather with me and a lot of other equipment. Never before did I dive with an O2ptima at such a high altitude. Also, I wanted to check how it would operate in sub-zero temperatures; the outside temperature was between minus 15 and minus 20 degrees Celsius.

The dives took place from this side of the lake, where a mountain river takes its origin, so the lake was not frozen solid there. We had to get under ice and not far from this place guidelines started with direction arrows. The dive site had to be accessed along a mountain slope; it was quite steep, so we used safety ropes. In order to make these dives happen, we had to carry down lots of equipment first, such as stage tanks, fins, masks, reels, etc. We had to make deposits in the river, then put on our dry suits, put on our rebreathers and enter the water along the guidelines. In the water we had to put on all the remaining equipment items such as fins, masks, stage tanks and go underwater quickly. After the dive we had to get out of water and uphill immediately, otherwise everything got frozen and it was not possible to take it off, because it was frozen solid and stiff.

These dives took 6 hours total time. The O2ptima rebreather worked flawlessly; I had no problems at all and at these temperatures (water temperature was 0 degrees Celsius) the warm, recirculated air from the rebreather did make a difference.
Also, our first stages did not get frozen, although they were not equipped with cold water kits. Only the battery went down quite fast, which is understandable on account of sub-zero temperatures though! We had no heated rooms at our disposal, so the O2ptimas were stored in a place with minus 10 temperature. They worked just fine the next day, in spite of these harsh conditions.

Overall, it was a series of test dives before an expedition to the mountain caves in Poland, which I am going to do with TOPR in March and April. We are also planning to dive in a site located at around 2000 m a s l. In order to get to such sites, one needs to walk for quite some time uphill, so if there is a possibility to dive with a closed circuit rebreather it can be beneficial on account of its reduced weight, as compared to a standard twin-tank system.

I cannot wait for the mountain dives in March and April. I will send an update afterwards.