Regional spreading of pollutants from fibre banks in the Bothnian Sea

Before 1969, waste and chemicals used in the Swedish forest industry (pulp and paper mills), were allowed to be discharged directly in nature, most often in the closest watercourse. Today, the pollutants are an environmental issue. Researchers will now investigate how far the pollutants can be transported with water currents and where they will end up. As a method they will incorporate tracers in the Swedish Coastal zone Model, in the outlet of Ångermanälven, as well as in the Nemo-Nordic model, for the open Bothnian sea.

The forest industry was a dominant industry and an important employer in the end of the 19th and in the 20th century in the county of Västernorrland, located on the northeast coast of Sweden. Residues, such as cellulose fibres, from the old pulp and paper mills can still be found as large banks of fibres (fibre banks) on the bottoms of lakes and the sea close to the old factories.

Before 1969, bi-products and used chemicals were discharged outside the factories, usually in the closest watercourse. The discharged pulp and chemicals were transported with the stream and accumulated in calm waters forming the fibre banks we can find today. The effluents consisted of cellulose and chemicals, such as mercury and chlorinated substances deriving from the different steps within the manufacturing process of pulp.

Within the efforts towards a non-toxic environment it is important to identify areas with high risk of elevated concentrations of toxic substances hazardous for biota. The aim with this project is to estimate with numerical models the spreading of released pollutants from the heavily contaminated fibre banks in the river mouth of Ångermanälven.

We will use the Swedish coastal zone model (SCM) to develop methods to trace released pollutants and investigate in present climate the spreading of pollutants from selected areas, e.g. outside the industries in Sandviken and Kramfors located in the inner part of the river mouth of Ångermanälven. In addition, we will similarly use the model NEMO-Nordic-SCOBI to investigate the spreading of the pollutants in the open Bothnian Sea as a continuation from the coastal zone.

Role of SMHI

SMHI is leading and responsible for all the work the project.

Collaboration/Project partners

We will work in close collaboration with researchers from SGU.

Funding and project period

The project is funded by SGU and the project period is 2018-01-01-- 2020-12-31.

Contact at SMHI

Elin Almroth Rosell.