Investigations of salt groundwater at Akvaforsk Research Institute, Sunndalsøra, Norway

Abstract

The Geological Survey of Norway (NGU) have assessed the possibilities for use of saline groundwater in fish-farming and research, through a research project at the aquaculture research institute AKVAFORSK at Sunndalsøra. From the data collected during the study, the following conclusions can be drawn: -Salt groundwater appears to have a high and stable mineralogical (inorganic chemical) quality, which is well suited to use in aquaculture. Its stable temperature is another positive factor. -The general bacterical content of saline groundwater appears significantly lower than in open seawater. -A high content of organic material can be a general problem in young delta sediments. It leads to reducing conditions and undesirable water quality, particularly as regards hydrogen sulphide, which is very toxic for fish. Further research should on glaciofluvial sediments (with low organic content) lying in hydraulic contact with seawater. -With large, localised abstractions of saline groundwater, it can be a problem to maintain the required high salinity level, due to \"freshwater intrusion\". This will occur particularly where rivers or fresh groundwater reserves drain towards, or into, the saline aquifer. Separation (e.g. two-level) pumping may be apossible solution to this problem.