March 16, 2021
online seminar

Experiences and good practices to tackle eutrophication in shallow lakes applying thin-layer sediment dredging technologies

Date of the event: March 16, 2021
Opportunity to participate in the event: online seminar

With about 600 km2 surface area, Lake Balaton is the largest freshwater lake in Central Europe and it is one of the most important natural treasures of Hungary. Just like in case of other shallow lakes, sediments play an important role in the nutrient cycling of Lake Balaton. As a result of high external loads of nutrients in the past, sediments became storages of such substances. The surface layer of sediments of shallow lakes can readily be resuspended due to wind induced wave action and contribute to the nutrient load (internal load) and, eventually to eutrophication which is manifested in harmful algal blooms. Removal of the most active, most polluted surface sediment layer (10-30 cm) by thin layer dredging is a common technique in water quality/eutrophication control. In addition to overall water quality improvement of a shallow lake, dredging may contribute to providing better quality and utility value for beaches and small-boat harbours.

The aim of the seminar was to draw attention to the importance and impacts of sediment dredging on large shallow lakes, and to introduce Hungarian and international dredging best practices and experiences.


8.00 – 8.30Joining to the online seminar / Short films and videos
8.30 – 8.40Welcome Remarks
Dr. Gábor Molnár, Managing Director, Lake Balaton Development Coordination Agency (LBDCA)
8.40 – 9.10Scientific background of sediment dredging in shallow lakes
Dr. Károly Kutics, Scientific Advisor (LBDCA)
9.10 – 9.40Good practices and experiences of shallow lake dredging in Japan
Tateno Satoru, Ministry of Land, Infrastructure, Transport and Tourism, Kanto Regional Development Bureau, Kasumigaura River Office
9.40 – 10.10Sediment dredging in Lake Balaton – experiences and plans
Dr. Károly Kutics, Scientific Advisor (LBDCA), representing the VIZITERV Environ Kft.
10.10 – 10.30Thin-layer sediment dredging practices and technologies with a focus on experiences in the Netherlands
Polite Laboyrie, Witteveen+Bos, the Netherlands, representing the Central Dredging Association (CEDA)
10.30 – 10.50Greenhouse gas emissions, water quality in freshwater lakes
Dr. Martine Kox, Deltares, the Netherlands, representing the Central Dredging Association (CEDA)
10.50 – 11.10Dredging practices and experiences in shallow water and siltation removal with Watermasters
Harri Uusi-Rauva, Vice President of Sales, Watermaster Aquamec Ltd.
11.10 – 11.40Discussion
11.40 – 11.45
Closing Remarks

The language of the event was Hungarian, English and Japan, with simultaneous interpretation. The seminar was organized on ZOOM platform.