A second glacial outburst flood began in the eastern Skaftá ice cauldron under Vatnajökull glacier late Saturday evening, RÚV reports. This flood follows a smaller one that originated in the western Skaftá ice cauldron and is expected to do as much damage to local communities and farmland as the last glacial outburst flood on the Skaftá river in 2018. The Department of Civil Protection is strongly advising that travelers stay away from the area and has raised their emergency response level to Alert Phase.
Floods in Skaftá are sourced from two ice cauldrons, formed due to persistent geothermal activity beneath Vatnajökull. On average, the cauldrons drain every two years, producing floods of up to 1,500 cubic metres per second. When the interval between floods is short, the flood tends to be smaller. The eastern cauldron is responsible for the largest floods. The river has flooded at least 58 times since 1955, with each cauldron usually draining at a two-year interval.
Smaller Flood, Same Damage
Owing to the speed at which the glacial flood began and water level increases in the first twelve hours of the flood, experts believed that the current outburst flood would be as big as the one in 2015, which is the largest such flood on record.
Happily, flood waters have been steadily abating since late Monday evening, leading experts to revise their original predictions. Nevertheless, major and widespread flooding is still a risk in the area. At time of writing, the flow at Eldvatn lake on the Skaftá river was just over 520 m3/s [18,363 ft3/s]. Flooding is expected to reach its peak tomorrow, Wednesday September 8, and waters are expected to continue to flood the region for another day or so after that.
Unfortunately, although the flood itself is expected to be smaller than it was in previous years, experts anticipate that it will do the same level of damage to surrounding settlements and farmland. This is, in part, because recent rains and runoff from the western ice cauldron, which flooded days before, have saturated the ground. As such, flood waters are more likely to spread further than they normally would.
‘We’ll just have to cross our fingers’
Glacial outburst floods are simply an unfortunate but unavoidable part of daily life for people in the area, remarked Skaftá district manager Sandra Brá Jóhannsdóttir in an interview on Tuesday before departing on a Coast Guard surveillance flight to determine what damage the flood has incurred thus far.
Authorities were particularly concerned about the wellbeing of the sheep grazing in the surrounding valleys. Local farmers spent the morning gathering their flocks and moving them to safer pastures in the event that the flood does continue to spread. Thankfully, no significant damage to structures or livestock had been reported at time of writing. “We’ll just have to cross our fingers,” said Sandra Brá. “It’s our hope, first and foremost, that the flooding is at least still at a consistent level and that hopefully, it will start to go down so that there will be less damage that occurred [in the area] in 2018 and 2015.”
The Skaftá glacial outburst flood in 2015 caused damage in the hundreds of millions of ISK (roughly $761,000; €708,000 at the time) and ten farms suffered damage to cultivated land and pasture. In 2018, flood waters covered Route 1, west of Kirkjubæjarklaustur.
In addition to warning that roadways in the area could quickly become impassable in the coming days, the Department of Civil Defense notes that glacial outburst floods can create hydrogen sulphide pollution, which can cause damage to the mucus membranes in the respitory tract and the eyes. Travelers are strongly advised to stay away from the area, which includes the Skaftárdalur valley near the southern coastal village of Kirkjubærjarklaustur, as well as around the Skaftárjökull, Tungnárjökull, and Síðjökull glaciers.