It’s a strange concept to consider that at the time of my birth, Lake Tasman was barely in existence. The Tasman glacier in Aoraki/Mount Cook National Park is New Zealand’s longest glacier at 27kms in length. It is, however, undergoing a rather fast rate of retreat and experts expect that it will eventually disappear completely. In the early 1970s, pockets of melt water became evident and over successive years these pockets increased in size and eventually merged to form the lake that exists today. The presence of the lake itself speeds up the retreat of the glacier, and now in 2014, the lake is over 7km long, with the glacier retreating at a rate of 500-800m per year. Within my lifetime, the lake is expected to reach its maximum size, and even over two visits 18 months apart I can see the difference in the lake.
The road to the Tasman glacier is not far from Mt Cook village, and was upgraded a couple of years ago to make it suitable for all cars. It was previously a dirt road suitable for only 4×4 in bad weather, so the area is now much more accessible all year round. From the DOC car park, the only spot with toilets, four different track options leave from here. I had arrived very early in the morning when the sun was just reaching over the peaks of the eastern mountain range, so parts of the walk were still in shadow. I headed first to the glacier viewpoint, the paths separating quite early on. Halfway along the left fork, the path splits again, the blue lakes one way and the glacier viewpoint the other. It’s neither a long nor taxing walk with only the latter section involving some rock hopping in a section that isn’t as well marked as the rest. I had the viewpoint to myself, and it was peaceful and quiet, just how I like it.
The lake is flanked on two sides by steep mountains including the backside of Aoraki/Mt Cook, New Zealand’s tallest mountain, with steep moraine walls piled high at the lakeside, a remnant from when the glacier was deeper and longer than its current position. In the distance, the glacier was visible, covered in dirt, and at the end of the lake, a few small icebergs floated near the river which escapes through the boulders strewn across the valley, before snaking towards Lake Pukaki. The boulders and moraine creates a barren, dirty-looking landscape which contrasts darkly against the blue-grey water of the lake. When I was here 18 months ago, there were more and larger icebergs on the lake than there were on this day. The photo on the info board at the viewpoint, taken just 3 years ago, shows a noticeable difference in position of the glacier’s terminal face which illustrates quite well the fast retreat of this glacier. Looking towards Lake Pukaki, the valley also looks barren, rocks strewn everywhere, with only the occasional hardy plant or bush poking through the debris.
Retracing my steps, I headed to the blue lakes, which are now green in colour. When they were named, they were glacier fed, providing the turquoise blue colour characteristic of glacial melt water, but with the retreating glaciers, the lakes are now rain-fed, allowing algal growth which gives the green colouration. A short path leads to the shore of the first of three lakes of varying shapes and sizes. Behind them, the mountains are scarred with avalanche paths and scree slopes. I had the lakes to myself also, and followed the path round the shore of the first lake and over the brow to the second and third lakes. In places, the path is broken with short sections of rock scrabbling, but other than these points, it is an easy to follow path. A pair of ducks mulled around on the second lake. The third lake was the largest and prettiest, especially with the sun by now reflecting off the surface giving it a brilliant blue-green colour. The area around the lakes was teeming with alpine vegetation, but unfortunately I was at least a month too early for the blooming of the colourful alpine flowers.
In stark contrast, the path to the lake side and river was a barren land of boulders and bare-looking bushes. I was surrounded by people as this path leads to the jetty where boats are boarded to tour the lake. A bus party of tourists were noisily chatting as they walked in procession along the gravel path, and I skirted round them as quickly as possible in an effort to return to some peace and quiet. After winding round the moraine wall, the path splits off to go to the river, and from here onwards, it is like walking through a sea of rocks. Boulders lie everywhere, and the river is very well hidden, deep down in the rock bed, until it appears all of a sudden as a colour contrast to the barren rocks that form its banks. The path ends on the moraine wall just above where the icebergs rest near the start of the river. A route down to the lake side is clear enough to follow, and I quickly headed down to the lake edge to stare directly at the icebergs at their resting spot. They weren’t the biggest icebergs I’ve seen, but looking at them dead on, they still provided a stunning vista as they shone in the sunlight with the snow-covered mountains beside them. I picked my way to the river and sat on a large rock to admire the view and watch the tourist boats pass by. It was a beautiful spot to sit until the flies realised I was a tasty meal. Bigger than sandflies, I’m not sure what they were, but I ended up bearing the marks of multiple suckers up my arms, legs and chest for days to come. I put up with the biting as long as I could tolerate before heading back to the car park and starting the long journey home.