Groundwater Surveys Begin in Oulu ‒ Goal Is to Secure and Improve Resilience of Water Supply
Geological Survey of Finland GTK will carry out in-depth groundwater surveys in the Oulu region. The aim is to secure water supply and improve the resilience of water supply in the City of Oulu. The OUVETUR project focuses on the less studied deeper esker sections of groundwater provinces.
Known groundwater resources in the Oulu region and the coastal area of North Ostrobothnia are scarce, and water quality issues are common. It has been necessary to acquire usable groundwater from further inland. However, there are groundwater areas in the City of Oulu where little research has been conducted on their deeper esker sections. Currently, water is mainly abstracted from the upper parts of the groundwater zone.
Surveys chart the groundwater potential of the Oulu region
Securing water supply in Oulu is critical for its over 216,000 inhabitants, the food industry and the local agriculture. Geological structural surveys of groundwater areas provide the necessary additional information on water supply options for the City of Oulu.
The project focuses on groundwater areas in Salonselkä in Oulunsalo, Hangaskangas, Kellonkangas in Haukipudas and Yli-Ii/Tannila region.
Over the next few years, many field surveys will be conducted at the research sites to determine the potential for water abstraction. In addition to geological surveys, geophysical surveys, soil drillings, installation of observation wells, water sampling, and well site surveys will be conducted in the groundwater areas. Observation wells are also used to determine the quality of groundwater and the concentrations of harmful substances.
“Poor groundwater quality in many places in the Oulu region is associated with the bedrock of the area, including black shale formation and poorly conductive claystone and siltstone in the Muhos formation. Groundwater surveys have often focused on the very surface of esker deposits, and knowledge of the deeper parts of these deposits has been lacking. This is notable especially because the coarse soil layers in the region may be up to 100 metres thick. For this reason, the OUVETUR project includes extensive geophysical surveys and soil drilling,” explains Project Manager Jari Hyvärinen from GTK.
Surveys will take two field work periods. More detailed information on field work is provided regionally before the work starts.
New information on groundwater resources in northern Finland and preparing for climate change
In addition to examining the resilience of supply, the project will examine the impacts of the changing climate on groundwater resources and water supply. As a result of climate change, the distribution of annual precipitation over seasons will change, and extreme weather phenomena will become more common. These changes may affect groundwater resources and water quality. It is important for water services to prepare for managing the risks of climate impacts.
In the project, GTK will also develop research methods related to deep groundwater, which will provide information on deeper deposits in aquifers. The project will increase expertise and understanding of groundwater resources in northern Finland.
The OUVETUR project will last until the end of 2027, and its total budget is approximately EUR 1.2 million, of which 80% is funded through the Council of Oulu Region from the European Union. GTK and Oulu Waterworks will contribute the remaining share.
Additional information
Jari Hyvärinen, Project Manager
Geological Survey of Finland GTK
jari.hyvarinen@gtk.fi
Eeva Käpyaho, Head of Unit
Geological Survey of Finland GTK
eeva.kapyaho@gtk.fi
