The purpose of this website is to disseminate information on natural hazards in Iceland related to glaciers.
The site is maintained by the Geophysics Division of the Science Institute.

 
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Characteristics of Lake Grćnalón         back

 

Location

/

Geographical coordinates

64°11´N
17°09´W

Name of
outlet glacier

Skeidarájökull

Lake type

Lateral

Type of dam
(e.g. ice, moraine)

ice dam

Risk of Damages

/

Downstream
topography

ice
rock
sander

Sediment /
Debris Content

low

Rockfall
into the lake

no

Failure
mechanism

hydraulic,
subglacial drainage

Mortality

one in 1898

Damages

road, bridges

Flow Characteristics

/

Length of floodpath

18 km

Flow path (e.g, subglacial, supraglacial)

marginal subglacial
and over land

- h (hydraulic head)(lake surface to flood plain, m)

558 – 110 = 448

Average grade

1.4 %

Flood river

Súla, Blautakvísl

References

/

Maps

I.Geod.Surv. (1939)
AMS (1945)
DMA (1982-1993)

Articles
(partial list)

see Main
Reference Site

Akselson 1936
 Kjartansson 1938 Thorarinsson 1939
Rist 1970,1973
Björnsson and Pálsson 1989

Aerial Images

Iceland Land Survey

Photographs

Helgi Björnsson

Lake Information

/

Lake level elevation  (m a.s.l.)

560 – 580

Depth (m)

 200 (1939)
150 (1989)

Area (km2)

18 (1939)
10 (1989)

Statistics

/

Flood interval

1 per year to
1 per several years

Flood Volume
(106 m3)

100 – 200

Peak discharge (m3/s)

1500 – 3000

Duration (days)

4 – 7

Time of peak discharge (day)

2 – 3

Lake level
change (m)

17 – 23

Flood dates

/

Flood dates
(partial list)

Sept. 1935; July 1939; Aug. 1969; Oct.1970; Sept. 2001