ECWA‑NOR

The naturally oligotrophic rivers in northern Sweden are generally characterized by a low pollution level and the water quality may still meet national standards for drinking water without further treatment. The occurrence of such clean surface waters is a rather unique feature within Europe as well as worldwide.

Factors like increasing summer tourism (hiking and biking) and new housing estates in the mountain regions increases the pressure on water quality in rivers and streams. The water in the rivers risk being contaminated by mainly fecal pollution from various sources, such as permanent households, holiday cabins and tourism.

In this project, we will investigate the possibilities to use E. coli in combination with eDNA as an indicator of water quality in oligotrophic rivers in northern Sweden. The study area will be the catchment area of upper parts of river Indalsälven, including the source area in the mountain region with the Norwegian border as delimiter to the west. This project aim to find connections between E-coli and environmental DNA (eDNA) to track the origin of the pollution in the water.  

Objective

The overall objective of this project is to investigate how E. coli can be used as an indicator for fecal pollution in an oligotrophic river in northern Sweden. Furthermore, the project aims to assess different methods to identify the source and strain of E. coli in the water by combining traditional and new innovative research methods. The project will generate knowledge that can be used in future efforts to predict and control pollution of river freshwater. Specific aims with the project are to:

1. Develop a scheme for relevant water sampling procedure and sampling points in the catchment area as well as in upstream locations in order to achieve representative data on E. coli prevalence.
2. Combine analyses of E. coli with environmental DNA (eDNA) on water samples in order to track the fecal contamination to a specific origin. eDNA will most likely be a useful tool in discovering E. coli strains directly from the samples without the need of cultivating the bacteria, which may detect strains that are difficult to detect.
3. In laboratory experiments, investigate the dependence of E.coli inactivation rate on physicochemical properties of the river water such as temperature, irradiance, pH, turbidity, organic matter and nutrients.
4. Perform multivariate statistical analyses in order to achieve better understanding of multi-factorial impact on E.coli decay rate as well as results from eDNA analysis. Develop GIS models which are highly predictive for potential bacterial outbreaks in the target areas.

The project group

Back row:
Monica Odlare, Robert Lundqvist, Anders Jonsson, Jon Hildahl, Jessica Sjöstedt, Anna Svedberg

Front row:
Michaela Hellström, Gibson Mhandu, Emmma Dufbäck, Johan Näslund.

Absent in the picture: Jonas Kråik