Dredging in Malmfjärden Bay in Kalmar, Southeast of Sweden
The LIFE SURE project has as main objective to test and demonstrate an innovative and cost-effective dredging system that minimizes the adverse effects on habitat loss, hydraulic entrainment, the release of contaminants, sedimentation, suspended sediment and underwater noise on the lake and surrounding area. Additionally, an evaluation of dredging effectiveness to be practically and economically feasible is required.
The main concept of LIFE SURE is to work within the circular economy approach in a way that dredged sediments should be viewed as a resource, not waste and. The LifeSure project is co-financed by the EU LIFE Programme and the Swedish Agency for Marine and Water Management (HaV). LIFE SURE is a project by the City of Kalmar and Linnaeus University.
The Malmfjärden is a shallow (max 1-2 meters depth) and semi-enclosed brackish bay, covering an area of ca 1 km2 on the west side of Öland Bridge. The hydrology of Malmfjärden bay is determined by its connections to the Baltic Sea and surface runoff from the surrounding catchment area. Malmfjärden has been used as a dumpsite and has received its fair share of pollution, the bay has high natural values sporting a rich flora and fauna. Additionally, the bay is occupied by protected bird species such as gulls, coot, warblers, and dabbling ducks. If left untreated, however, Malmfjärden is at risk of suffering the effects of eutrophication. With the advent of a new residential area at Malmfjärden, the bay must be remedied to keep good vitals that provides a sustainable environment for future generations of Kalmar.
The goal of the LIFE SURE project is to restore Malmfjärden to achieve good ecological status, for today and tomorrow. One way to achieve this is via dredging, where eutrophicated top-layer sediments are removed and then treated in a nearby facility. Pollutant levels will decrease, and ecological status will increase – Malmfjärden bay will be a living, attractive and sustainable area for humans, animals, and plants.
We are working on a dredging concept that is highly innovative as it is mobile, cost-effective, environmentally friendly and easy to use. We are working with a dredging robot, made for shallow waters. The dredging process is that the under-unit robot moves slowly forward and carefully pumps up sediments. The dredging is done carefully to avoid resuspension- and disturbances in the surrounding marine environment. The robot can run both continuous as well as automatically.
The dredged sludge is pumped onto land where it enters the treatment plant. At the plant, the sediments are dewatered and several parameters are continuously measured. The water from dewatering is treated and discharged and the sediments are taking care of. The LIFE SURE project introduces a resource approach based on the potential to used sediments as a resource for new material. The use of dredged sediments in applications that are beneficial and in harmony to natural development include final cover landfill closured, in build engineering and modern agriculture such as fertilizer, soil amendments and plant-growing material.
A1. Planning and preparation for the stages in the project (completed).
B1. Construction of the dredging equipment and dewatering and treatment site (completed)
B2. To know how to fully use the equipment in full scale, the system was tested on small scale (completed)
B3. Based on the knowledge of the small scale test, LIFE SURE is currently running a full-scale demonstration
C1. LIFE SURE is continuously monitoring and evaluating the effects and results of the project activities
D1. LIFE SURE is actively informing and spreading knowledge and results from the project.
D2. Replication and transferability
The LIFE SURE project has as main objective to test and demonstrate an innovative dredging system.
The LIFE SURE project works with two concepts: circular economy and innovative dredging methods.
Follow the actions and activities in LIFE SURE
Demonstration of a non-conventional dredging technology and use of sediment uptake.
The bay of Malmfjärden is a semi-enclosed shallow bay located in a central part of Kalmar city.