Microbiological Potential of Infiltration Beds

There is a growing focus on the role of cities in relieving the sewage system through nature-based climate adaptation solutions that also promote biodiversity. These solutions are increasingly being used by many municipalities and utility companies in their green initiatives.

However, the use of infiltration beds for rainwater treatment is limited due to strict requirements and a lack of documentation. Therefore, VIA University College, Byblomst, Byggros, and Silkeborg Forsyning joined forces in a knowledge bridge project with the aim of investigating and documenting the properties of the microorganisms in the beds.

Through strong collaboration, the partners have used each other’s knowledge to explore the microbiological potential of infiltration beds. At the same time, they have managed to set up an innovative pilot-scale setup where you can see and measure the filtration effect of the different soil layers as well as the microbiology. This has given the partners greater insight into the effects within a wide range of parameters and gives them the hope of eventually being able to document how plant composition, microorganisms, and soil interact in water purification so that the solution can be spread to more locations.

Simulated reality provides insight into the purification effects of an infiltration bed.

At Byggros on Funen, the project team has set up a number of pilot-scale setups where tanks containing different plants and soil compositions have been tested for cleaning effects. The different setups have light panels and every other day a controlled irrigation is run over the different tanks, simulating real-life conditions.

We have designed a pilot scale setup that can show the interaction between soil, plants and microorganisms – this is a very important result that will also be used in the future. – Ditte Andreasen Søborg, Project Manager, VIA University College.

During the project, Byggros has hired an industrial PhD who will follow up on the results and continue analyzing the pilot-scale setup to gain a more detailed insight into the purification processes and the microbiological potential. At the same time, ByBlomst has gained greater insight into the importance of choosing plants that can help compete with other players in the market:

We constantly need to become better and smarter to be competitive, and a knowledge bridge project is super relevant and interesting! – Mette Lorentzen, Director, Byblomst.

A fruitful collaboration that provided an extra layer of knowledge for climate adaptation

With the results in hand and a process that has given the partners more opportunities, they are all one step closer to helping municipalities and utilities spread the solution:

It’s important for us to understand how the plants develop in these types of beds so that we can make the best possible decisions when choosing plants in the future. I hope that the results can validate the solution with SUDS beds so that municipalities’ hesitation is minimized, and the beds are used more. The Knowledge Bridge project has given us an extra layer of knowledge. – Mette Lorentzen, Byblomst.

The group has chosen to meet outside the project to discuss the results of the project and the further course of action. However, one thing is already clear: the project has provided insight into treatment effects and rainwater solutions.