Implementing smart energy management concepts in WWTPs






In the map below, you can find examples of water protection measures within this topic. These actions are picked from the Bank of Actions - if you are interested to browse other water protection actions, visit the Bank of Actions.


Awareness raising

Hazardous materials

Littering etc.

Oil spill prevention

Research and monitoring

Shipping and boating

Stormwater management

Strategies and programs

Wastewater management


Drainage basin

Agile experiment: trialing new type of litter collecting vessel and water treatment

Actor: Clewat Ltd   ●   Year: 2020   ●   Address:

Clewat Oy trialled over the summer and autumn 2020 a new type of Cleansweep trash collecting vessel in Helsinki waters. The tests were conducted to determine how well the vessel performs in controlling the amount of marine litter. Clewat was working in cooperation with the City of Helsinki construction services Stara. Stara is in charge of cleaning waters in the sea areas and waste management in the archipelago. Last year Stara collected roughly 80 cubic metres from the coast of Helsinki with its Lippo vessel.


Clewat Oy was selected to join the Baltic Sea Challenge speedy experiments to determine the quantity and quality of the plastic litter collected by its vessel especially in sea areas that are challenging to keep clean. The Cleansweep vessel was operating in Kalasatama, Vanhankaupunginlahti and Töölönlahti in June, August and October 2020. Stara tested the performance and operation of the Cleansweep vessel and comparing it to the Lippo vessel for a period of one month. The objective was to develop and streamline trash collection so that small plastic particles could also be collected.


The operation of the vessel is based on the utilisation of water flow and is capable of collecting plastic particles from 0.5 mm in size. The amount of waste collected in all areas was clearly higher during the summer than in October. In the summer the litter collected consisted particularly of food and drink as well as to these related packaging materials. In addition, construction materials were found. As a result of the experiment, several significant modifications were made to the vessel to further improve its operation.

Background information

Four experiments to combat marine litter in the Baltic Sea received altogether 50 000 euros of support from the City of Helsinki. The experiments were conducted during 2020 in Helsinki’s coastal and sea areas to find innovative new means to prevent plastic waste in the Baltic Sea. 

Watch the video presenting Clewat's speedy experiment

Read the news on the results of all of the experiments (City of Helsinki, 20 Jan 2021)

Further information

Name: Keijo Säilynoja   ●  Email: keijo.sailynoja(a)   ●  Web page:

Guidelines & Recommendations

Guidelines & Recommendations