Landslide Recovery in Fiordlands National Park
November 03, 2010
Fiordlands National Park in southwest New Zealand is one of the wettest areas in the world, receiving 284 inches (7200 mm) of rain per year, with 270 days of precipitation annually. In 1999, the worst rains in a century were recorded in southern New Zealand. Still, my plan was to hike the George Sound Track in Fiordlands Park even though I had been warned of rockslides and flooded areas, and that the track may not even exist anymore. As I arrived at the park, near Henry Saddle overlooking the Katherine Valley (top photo), I realized that I was likely the first person to see the large slip (landslide) in the midground. To give you an idea of the size, the bare area is about 230 feet (70 m) wide at the bottom. When I crossed the slip several hours later, there were boulders the size of houses in the debris, and trees (still with their leaves) were strewn about in the debris field.
In 2007, I returned to the track (middle photo), and the first thing I noticed was how much darker the slide area looked from the same vantage point as in 1999. The slip was recovering. Lake Katherine is just visible further down the valley. When crossing the slip, the footing in the rocks was much more stable now. But most noticeable was how much the vegetation had recovered during the intervening years (bottom photo). Mosses, quite prevalent in the wet enviroment of Fiordlands, were overruning everything. Henry Saddle, where the first two pictures were taken, is above the dead tree sticking up in the center of the bottom photo.