The amount of microplastics gathered by filtering stormwater equals nearly 2,000 residents’ annual plastic usage

News 12.01.2020

By covering half of the built area in the Helsinki Region with filtration chests, 193 tonnes of micro­plastics could be gathered from storm­water every year. That equals the amount of plastics used by nearly 2,000 Finnish residents annually. Currently approx. 2,300 tonnes of micro­plastics end up in storm­water annually in the Helsinki Region.

Stormwaters carry harmful emissions, such as microplastics and heavy metals, into water bodies and the rest of the environment. The Stormwater Quality Management project developed new solutions for stormwater treatment and quality monitoring that are in demand worldwide.

The Stormwater Quality Management change project tested new stormwater treatment and management methods at seven different locations. There will be high demand in the future for the solutions created in the project, both in Finland and abroad. As cities are built to be even denser, stormwater management has to be considered more carefully in urban planning. Climate change also affects how we manage stormwater.

“The general public is also becoming increasingly aware of the environmental damage caused by stormwater. This puts more pressure on designing and implementing new solutions. The results of this project are therefore a good starting point for the future”, says Project Manager Juhani Järveläinen from the City of Lahti.

The new methods tested in the project included, among other things, an underground wetland meant for airport stormwater treatment, a filtration chest for street water purification and a floating dock solution for managing mixed sewer overflows. The solutions were tested in Lahti, Espoo, Vantaa and Helsinki. 

In addition to creating and testing practical solutions, one of the goals of the project was to disseminate research information on stormwater quality requirements and the need for quality management.  

“I think we were successful in sharing the information. Based on the work done in the project, it’s clear that the industry’s actors have a shared need to develop stormwater quality management”, Järveläinen states. 

It is therefore important that the performance of the methods developed and implemented in the project continue to be monitored. An essential part of monitoring their performance is stormwater quality measurement technologies, which were developed in the project by Sensmet Oy and universities, for example.   

“The product development started in the project continues. The experiences and knowledge acquired during the project will serve as a basis for bringing new products to market. We will still meet with the steering group in 2020 and try to promote the activity of the networks formed in the projects”, Järveläinen says.