No Signs Yet of Imminent Múlakvísl Glacial Outburst Flood
So far, there have been no clear signs of the Múlakvísl jökulhlaup, or glacial outburst flood, which is expected to happen in the coming days or weeks. A GPS monitor has been put up in one of the calderas in Mýrdalsjökull glacier which will give more information on the timing of the flood. Salóme Jórunn Bernharðsdóttir, a natural hazard specialist at the Icelandic Meteorological Institute, states the institute is watching proceedings in Múlakvísl closely. So far, there have been no signs that the glacial outburst flood has started.
The newly installed GPS monitor is hoped to give clues about an imminent flood one to two days before the flood reaches the Múlakvísl river crossing at Route 1. Salóme stated that earthquake measurement devices should also display some disturbances around four to six hours before the flood reaches the bridge. Furthermore, electric conductivity should increase in Múlakvísl river before the flood happens. When water levels have risen at Léréftshöfuð, which is six kilometres north of the Múlakvísl river, the flood will reach the Route 1 crossing in half an hour to an hour.
The geothermal heat under the Mýrdalsjökull glacier causes water to collect in the calderas, causing regular glacial outburst floods in the area. Normally, the floods take place a little later in the summer when the mid-summer thaw at Mýrdalsjökull. The amount of water under Mýrdalsjökull glacier has led scientist to believe a glacial outburst flood is imminent. Last year, 2018, there was no flood so a considerable amount of water has collected under the glacier. The flood is expected to be the largest one in eight years, when the 2011 flood ruptured the Route 1 crossing the Múlakvísl river east of Vík í Mýrdal.
Information for travellers
At this point in time, it is believed that it is not necessary to close roads. That situation could change quickly, however, and authorities will step in if they believe a flood is about to occur.
What can happen, and how should travellers react?
Dangers which accompany a glacial outburst flood in Múlakvísl river:
– Floodwater can block the route from Route 1 towards Kötlujökull glacier west of Hafursey.
– Floodwater can flood over and block, or even rupture, Route 1 at the bridge crossing of Múlakvísl river.
– Floodwater can block the route into Þakgil.
– The gas hydrogen sulphide could be found in copious amounts close to Múlakvísl river. The gas can burn mucous membrane in the eyes and in the respiratory tract
– Respect road closures, as well as evacuations if they should occur.
– Keep away from the Múlakvísl river when a glacial outburst flood is occurring.
– Avoid places affected by gas pollution, such as along the river as well as in depressions nearby by it. Do not stop at the bridge crossing Múlakvísl or Skálm.
For those looking to keep a watchful eye on the proceedings when the flood occurs, this webcam of the Láguhvolar area should provide a view of the flood: http://brunnur.vedur.is/myndir/webcam/2019/07/04/webcam_laguhvolar.html
Travellers passing through the area are instructed to head to the website of the Icelandic Road and Coastal Administration, www.road.is, for further information on road conditions, or call 1777.