Supported by Odense Kommune (60,000 DKK) in the period from 1 May to 30 September 2015

Odense Harbour shows a high degree of eutrophication due to sewage after heavy rain falls (about 20 times per year). Since the abatement of ship traffic in the innermost part of the harbour, Odense Kommune is looking for new ways of usage for this centrally located urban site. Touristic activities, such as cultural demonstrations, swimming, and water sports (e.g. kayak polo) are planned and partly already realised. To increase the possibilities of leisure activities, the water clarity in this area shall be improved. Eutrophication and limited water exchange might be driving forces for the high turbidity and phytoplankton densities. Therefore, Odense Kommune called for meetings with Nordshell (collaboration with Mads Anker van Deurs) and University of Southern Denmark (SDU) to develop a mussel project to improve the water quality by means of their great filtration capacity.

The present pilot study, wich is conducted in close cooperation with NordShell, aims to assess the feasibility of cleaning the sea water in Odense harbour by means of a large number of filter-feeding blue mussels (Mytilus edulis) on ropes/nets suspended from floating ‘smart-farm units’. The first step will be to study the actual weight-specific growth rate of mussels of various shell length suspended in net-bags at selected sites within the harbour area in order to evaluate to what degree the mussels are able to realize their growth potential at the prevailing low salinity and high phytoplankton biomass. Different ambient phytoplankton concentrations presumably above the upper saturation level for maximal filtration, shall give insights into the ability of mussels to exploit their filtration capacity. Finally, the potential water-cleaning effects and suitable sites for the installation of 'smart-farm units' (number, size, and density of mussels) will be evaluated.

For further information please contact:

Hans Ulrik Riisgård:

Florian Lüskow:

Experimental study site (left) and a nearby info poster about the mussel project

Left: Odense Harbour with 5 indicated study sites  (source: Google Maps). Right: Baojun Tang and Per Andrup measuring  temperature, salinity and chlorophyll a profiles in the harbour.

Inputs of nutrients and sewage to Odense Harbour caused by heavy rainfall (4 to 20 times per year) .

News (in Danish):

Fyens Stiftstidende


1st Meeting Odense Harbour Mussel Project 26 June 2015

2nd Meeting Odense Harbour Mussel Project 21 September 2015

Final report from the mussel project 25 September 2015

Projektet samarbejder med Kerteminde Maritime Haver:

Presentation of mussel project, Odense Slot 21 September 2015