2.12 Dust Pollution

Indicator 2.12 - Dust Pollution

2.12-fallryksmaelingar-yfirlitsmynd              2.12 Fallryksmælir Hafrahvömmum                

Location of dust meters             Dust meter in Hafrahvammar           Web cam monitoring dust pollution  from 
                                                                                                                       Hálslón reservoir.

Click for larger images.


Air quality limits for particulates according to regulation 817/2002 are following.  A good state = < 5 g/m2 per month, acceptable 5 - 10 g/m2 per month and unacceptable state => 10 g/m2 per month.

Aeolian deposition and atmospheric dust measurements have been ongoing since 2005, providing a solid experience on the operation of the meters as well as information on the dust pollution from coastal areas of Hálslón reservoir.

Of 548 measurements the results have three times exceeded 10 g/m2 per month and in all three cases the cause was unrelated to Hálslón reservoir.  542 measurements have been <5 g/m2 per month. Information on measurements of previous years can be found in the reports of the relevant measures under the tab "additional resources" (only in Icelandic).

Among other things in view of these findings the focus in monitoring was changed in the summer of 2013.  Meters measuring the deposition of dust per unit area each month were reduced to five.  Instead webcams,  -based at the north end of Hálslón reservoir (see figure ), were used to evaluate aeolian deposition and atmospheric dust from the reservoir.  This method gives frequency, density and magnitude of aeolian dust classified into five categories (1 - 5) where the rising number refers to increased dust density.

Following are the results of dust density in 2015 and 2016.

Table 1a:
Deposition of dust in the summer 2016. 

  Inhabited areas  East of Hálslón West of Hálslón 
Period  1 Strönd
4 Hvanná 


10 Búrf.tögl


7 Kofaalda 


8 Sauðárdalur


 June/July  3.158  0.783  0.156  -  -
 July/August  0.367  0.379  0.16  0.052  0.095
 August/September  0.043  0.062  0.062  0.043  0.037

Table 1a shows results for the summer 2016. In all cases < 5/g/m2.


Table 1b: Deposition of dust in the summer 2015. 

  Inhabited areas  East of Hálslón West of Hálslón 
Period   1 Strönd
4 Hvanná 


 10 Búrf.tögl


7 Kofaalda 


 8 Sauðárdalur


 June/July  0.249  0.147  0.143  -  -
 July/August  1.274  0.274  0.079  0.099  0.066
 August/September  0.099  0.353  0.118  3.024  0.197
 September/October  0.271  0.453  0.388  0.567  1.032

Table 1b shows results for the summer 2015. In all cases < 5/g/m2.

Monitoring by web cams

Table 2a. Number of hours, mineral dust was seen through webcams by Hálslón reservoir in summer 2016.

Date Classification of measurements  Water level of reservoir
1 2 3
June 28 5.0 - - 592.6
June 19
2.5 - - 593.1
June 23 1.45 - - 595.1
June 24 6.15 - - 595.8
June 25 0.5 0.5 - 596.6
July 14 3.5 - - 606.3
July 15 1.0 - - 606.8
August 16 0.5 - - 622.9
Hours in total 20.6 0.5    

Dust from Hálslón reservoir was registered in 8 days (21.1 hours) during the summer 2016. Most of the time it was level 1, or for 20.6 hours. Once it was level 2 for 0.5 hour. Level 3, 4 and 5 was never detected.

Table 2b. Number of hours, mineral dust was seen through webcams by Hálslón reservoir in summer 2015.

 Date  Classification of measurements Water level of reservoir
1 2 3
 June 26 4.25  1.75  -  581.4
 Hours in total
4.25   1.75    

Source: Landsvirkjun 2017
: August 2017

Targets & Monitoring Plan

Monitoring Protocol from 2013

Dust meters set up each spring.  In the highlands the meters are installed as soon as snow melts and the area is passable.  Dust meters in populated areas are often installed one month earlier.  Information is gathered once per month during summer until first snow in the fall.  Three dust meters are positioned near Hálslón reservoir (no 7:Kofaflói wetland, no 8 Sauðárdalur valley and no 10 Búrfellstögl mountain) and two in inhabited areas (no 1 – Strönd farm and no 4: Hvanná farm).

Web cams positioned at Kárahnjúkar peaks are used to monitor dust pollution.  This method gives information about frequency and magnitude of dust pollution in real time.  The webcams can be viewed on Landsvirkjun's homepage.

Monitoring protocol until 2013

Until 2013 average monthly concentration of air particulates was measured using up to 18 monitoring stations.

  • Monitoring stations in inhabited areas:  Strönd, Hólmatunga, Hvanná, Brú farms.
  • Monitoring stations East of Hálslón reservoir:  Búrfellstögl mountain, SW of Sandfell mountain, in Lindir springs, Kofaalda hill and Sauðá river.
  • Monitoring stations north of Hálslón reservoir:  Hafrahvammar canyon, Hallarfjall mountain and Smjörtungur area.
  • Monitoring stations in Brúaröræfi wilderness:  Fagridalur valley, Arnardalur valley and Breiðastykki area.

Landsvirkjun has planned countermeasures for the dust pollution, see indicator 2.29: Sand Enroachment by Hálslón Reservoir.


Dust will not increase over time in Fljótsdalshérað.

Possible countermeasures

Several methods are available to counteract aeolian deposition. For now it is just monitored.

Changes in Indicator

In the third phase of the Sustainability Initiative, the changes were made in the English version of the indicator that it was considered that the origin of dust should not be examined. The reason for the change is that there is no standard method of measuring this.

In the fourth phase of the Sustainability Initiative, it was decided to change the numbers of sustainability indicators. This indicator was originally number 17.1, which is covered by the number in the progress report from 2004 and 2005.

Rationale for Indicator Selection

Dust from Halslon Reservoir is a direct project effect that will be monitored in this initiative. However, it could prove difficult to distinguish dust from the reservoir from dust originating from other sources, unrelated to the project. During dry windy days dust from the highland areas north of Vatnajökul Glacier is carried into the atmosphere and may in some cases impair visibility in the lowlands in north eastern Iceland.

Every year, sediment load from Jökulsá in Dal, which was earlier carried to the sea, settles as a thin layer of silt  on the drawdown areas of Hálslón Reservoir. In May, the water level is at its lowest in Hálslón but in June it starts rising, so in the beginning of August, the reservoir is full. The water level of Hálslón fluctuates in the average year for about 45 metres, but in the dryest years the fluctuation can be up to 65 metres.

The silt will for the first decades settle in the reservoir by the glacier roots. During the summer when the reservoir level is low the silt may be eroded by strong dry winds from the south or southwest and thus increase the amount of suspended material in the air. The finest grained fraction of the natural soil in the drawdown areas may also contribute. A layer of mist will then be carried to the northeast over the moors and down into populated areas.

When unobstructed, Jökulsá á Dal carries its suspended sediment load to the ocean leaving some in dry flood channel in the lowlands. Dust originating from these area will no longer be present.


During strong dry winds from south and southwest dust from the highlands north of the Vatnajökull Glacier is carried north and northeast across the highland plateau and down the lowlands. Under these conditions and during low flow in the Jökulsá á Dal fine grained material from dry the river channels and river banks in the lowlands contributes to the amount of suspended material in the air.

No special measurements had been made before baseline data was collected, but the baseline condition was assessed by measuring particulates in the air near Hálslón and by Jökulsá river in Dal, up to the time when the effects from the Kárahnjúkar projects started to show.

Act No. 817/2002 on air quality limits for particulates states that the concentration of particulates that are not water soluble must no exceed 10 g/m² per month of collection. The definition for particulates is dust that settles by itself on a humid surface (Act No. 817/2002). Particulate count between 5 and 10 g/m² in a 30-day period is considered acceptable, and if it is less than 5 g/m², that is considered good.

The graphs below show particulate counts in a few measuring stations in 2006. To see the location of the stations, click here.





Additional Resources

Annual reports made by East Iceland Natural History Institute for Landsvirkjun on dust pollution near Hálslón reservoir, in Brúaröræfi wilderness and int populated areas in Fljótsdalshérað municipality. (Only in Icelandic)

Results of measurements 2014 can be found here.

Fallryksmælingar við Hálslón og í Byggð á Fljótsdalshéraði sumarið 2013.  Landsvirkjun report no: LV-2014-042

Click here to download report

vísir 2.12 fallryk 2011 forsíðaKárahnjúkavirkjun - Fallryksmælingar við Hálslón, á Brúaröræfum og í byggð á Fljótsdalshéraði sumarð 2011.  Landsvirkjun report no: LV-2012-023

Click here to download report

2.12-LV-2011-030-mynd-forsida-2010Kárahnjúkavirkjun - Fallryksmælingar við Hálslón, á Brúaröræfum og í byggð á Fljótsdalshéraði sumarið 2010.  Landsvirkjun report no: LV-2011-030

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2.12-LV-2010-43-mynd-forsida-fallryksmaelingar-sumar-2009Kárahnjúkavirkjun - Fallryksmælingar við Hálslón, á Brúaröræfum og í byggð á Fljótsdalshéraði sumarið 2009.  Landsvirkjun report no: LV-2010-043

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2.12-LV-2009-003-2008-mynd-forsidaKárahnjúkavirkjun - Fallryksmælingar á Brúaröræfum, við Hálslón og á Fljótsdalshéraði sumarið 2008.  Landsvirkjun report no: LV-2009-003

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Kárahnjúkavirkjun - Fallryksmælingar við Hálslón og í byggð Sumarið 2005. Landsvirkjun report no: LV-2006-002

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Satellite image of sandstorm and dust pollution north of Vatnajökull

MODIS images