Sammendrag
This report presents results from the monitoring of biological and chemical status in the lower part of
the Glomma, in the vicinity of Nordic Paper AS. The objective of the survey was to assess the effects
of the factory's effluent on the river. The factory belongs to the “land-based industry” and
"production of paper and cardboard” sectors and is in the lower part of the river Glomma near
Greåker in Sarpsborg municipality in Østfold. After treatment, the wastewater is discharged to the
water body 002-3551-R (Glomma fra Greåker til sjøen), which is classified as having bad ecological
status, with the risk of not meeting the environmental goal, of good ecological status, by 2021.
Three biological quality elements, benthic macroinvertebrates, benthic algae and heterotrophic
growth, were examined at five sites, two sites upstream of Nordic Paper's effluent, two downstream
and one site in Visterflo / Ågårdselva, a tributary merging with the Glomma just downstream of
Nordic Paper. Priority substances and river-basin specific pollutants were sampled at two sites, one
upstream and one downstream of the factory's effluent.
In an overall assessment of ecological status, all sites, both in 2015 and in 2018, were classified as
poor or bad status according to the guidelines in “vannforskriften” (the Norwegian implementation
of the Water Framework Directive). Since it was primarily macroinvertebrates and heterotrophic
growth that were decisive in the classification, organic pollution and not eutrophication seems to be
the main problem in the lower parts of Glomma.
Both sites where priority substances were analysed were in good chemical status, well below the AAEQS.
For river-basin specific pollutants (which are included in the assessment of ecological status) the
concentration of zinc was above the AA-EQS at the station downstream of Nordic Paper's discharge.
The elevated concentration of zinc is most likely due to the water sampling being conducted in the
factory’s effluent water, as the surface discharge point is 50 m upstream. The measured
concentration of zinc was higher than the regular concentration of the factory’s effluent water.
Overall, this shows that the two water bodies examined do not meet the environmental goal of good
ecological status, and that organic pollution is the main reason for this. At the same time, it shows
that Nordic Paper's effluent is only a small part of the cause of the poor status downstream of the
factory. This is because the ecological status upstream of Nordic Paper is also classified as poor
status, because the area is heavily influenced by other industries and urbanized areas, with several
large discharges directly to the water body. This most likely masks the effect of Nordic Paper's
effluent on the ecology of the river.
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