Issues
Areas
Solutions
TRL Level
SRL Level

Nearly 40% of people in the US live with unhealthy air pollution, report says

The number of people living with levels of air pollution that can significantly affect their heal...

Helsinki’s stormwater filtration unit

Urban floods are identified as one of Helsinki’s most important climate hazards. Coupled with population growth and densifying urban structure, flood risk is likely to increase significantly. Apart from problems arising from the water being in the wrong place at the wrong moment, the poor quality of stormwater is a serious issue for the receiving water bodies. In the downtown Helsinki, the stormwater is discharged to the Gulf of Finland which is already suffering from excess nutrient load and other pollutants causing many harmful impacts in the ecosystem and reducing the recreational value. However, stormwater management requires space, which is very limited in the city. To meet this challenge, the City of Helsinki is testing a new nature-based solution in Taivallahti area, close to the city centre. The stormwater will be lead through a stormwater filtration unit to be purified before being discharged to the Gulf of Finland. The filtration unit will reduce the concentrations of solid substances, litter and different harmful substances such as microplastics. The pilot has been developed by by Olli Hakala from WSP Finland and Aalto University and it will be implemented in the Smart & Clean Stormwater project. The project has received funding from the Helsinki-Uusimaa Regional Council.

Developed by City of Helsinki & WSP Finland Ltd

The filtration unit will be built in autumn 2018 and its schedule follows the construction of the separate sewage piping in Mechelininkatu and Eteläinen Hesperiankatu. The filtration unit will be located at an outfall of a stormwater pipe that gathers stormwater from heavily trafficked roads. Depending on the rain event, the filtration unit will capture part of the stormwater which would otherwise be discharged to the sea without a treatment.

TRL5. Laboratory testing of integrated system
Technology validated in relevant environment. Fidelity of breadboard technology increases significantly. The basic technological components are integrated with reasonably realistic supporting elements so they can be tested in a simulated environment. Examples include “high-fidelity” laboratory integration of components. The innovation has been validated in lab: a prototype was built and flow measurements were taken. Different filter materials have been tested in another project by VTT. The filtration unit will be built in autumn 2018 and monitoring will be set up late 2018.

See more information about this level and the TRL and SRL levels.

The main components of the system have been tested separately, and an initial integration exercise has been conducted.

Credits
Collaborators

How does it work?

Objective of Helsinki’s stormwater filtration unit is to clean stormwater mechanically without input of external energy. The purification process is based on sedimentation (detention basin) and filtration.

Limitations/conditions under which this innovation does not work or is less effective

The stormwater filtration unit requires a certain flow of stormwater. In case the unit receives too much water for a long period, the filtration efficiency can be compromised. In the future use cases, this can be avoided by storage and retention systems to allow only a certain amount of water enter the filtration unit at a time. In the current pilot, a limited maximum amount of stormwater enters the pilot and the overflowing for a too long time will not happen. An important part of the monitoring is to find out how often the pilot needs maintenance and how often the filter material needs to be changed due to clogging.

Added value
Products for stormwater retention and storage already exist on market, but more productized solutions for cleaning stormwater are needed especially for colder climates. The stormwater filtration unit is scalable and can be modified to fit many different conditions. It functions without external power supply and unlike many other solutions for stormwater treatment, it doesn’t need plants to purify the water. The filtration unit has many possible uses in the city area thanks to its compact size, integrativeness and modularity. By adjusting inlet and outlet elevations, storage and filter volumes and shapes, the hydraulics of the stormwater filtration unit can be modified. All dimensions and elevations are sitespecific and based on stormwater flow rates. In the on-going Smart & Clean Stormwater project, the unit will be mounted in the ground and the water will be discharged to the sea after the treatment. However, it would be possible to use the filtration units on very different sites in the city as a part of the urban environment and re-use the purified water as an recreational element. stormwater is usually seen as a nuisance rather than a resource in city planning. While the city structure becomes more densely built, blue-green spaces become more and more important improving health and well-being of the citizens as well as providing habitats for species. Future use cases would ideally include using the filter unit as a landscape element.

Oh! You need to log in to access this information.
Not a member yet? No worries, you can register here.

Other

innovations

Other Sonja-Maria Ignatius innovations
Urban floods are identified as one of Helsinki’s most important climate hazards. Coupled with pop...

Want to explore
some more?

Head on over to our ?
page to find other materials organized by different categories.

Welcome back!

Log in to stay connected with your
favorite innovators

Not a member yet?
No worries, you can register here.

Create account

Enter some personal details
and you’re good to go!
Name *
E-mail *
Password *
Confirm Password *
Already a member? login here

Welcome back!

Log in to stay connected with your
favorite innovators

Not a member yet?
No worries, you can register here.

Create account

Enter some personal details
and you’re good to go!

Name *
E-mail *
Password *
Confirm Password *
Already a member? login here

Supported by

flag_eu_gray

By

Share this

Sonja-Maria Ignatius

innovation

You know what they say, sharing is caring! You can share this innovation with as many people you feel will be interested in it.
Tip: include a message about why it caught your eye.

Connect with

Sonja-Maria Ignatius

Did something peak your interest? You can share any questions, praises, comments, or concerns and the company will recieve them directly. No need for middle-men here.

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

Filter

Issues
Areas
Solutions
TRL Level
SRL Level