14 June 2010

Attabad – a further twist in the tail

Posted by Dave Petley

Over the weekend the water level in the lake at Attabad has started to rise once again (see the monitoring site), presumably indicating that the warm weather in the Hunza region is increasing the rate of snowmelt, and therefore of inflow to the lake.  The continued choke on flow being imposed by the large boulders in the channel is clear.  The channel itself continues to evolve slowly through widening (image from Focus as per usual):

 The amount of scour in the downstream portion of the channel is remarkably impressive:

 It would appear that development of the the channel continues to be impeded by a small number of critical boulders, one of which may well be below the water level, protecting the stream bed against downcutting.  The Pamir Times images of the site, available in this gallery, are quite instructive.  This composite image in particular is interesting, clearly showing how the boulders are controlling the discharge:

Meanwhile, landslides continue to occur with a high frequency in the Attabad area (Focus image):