Water quality improvement in the city of Arvika, SwedenThe Swedish city of Arvika is located near lake Kyrkviken, which is connected to the larger lake Glafsfjorden. In the year 2000, after weeks of rain, lots of water from lake Glafsfjorden entered the smaller lake Kyrkviken, flooding into the city and causing lots of damage. Besides this, Arvika is dealing with more frequent extreme weather events on the water quality.
What is the pilot about and what problem does it solve?
In this CATCH pilot project, Arvika worked on improving the water quality of lake Kyrkviken. The project aimed to reduce the amount of phosphorous that ends up in the lake through stormwater from the city and adjacent land uses. This action has contributed to address the issue of eutrophication and oxygen deficiency within the lake. The project is co-financed by NSR.
What measures were taken
The water quality improvement measures consist of floating screens and constructed wetlands.
The screens, which are in place since the end of 2019, divert the stormwater into existing vegetation. This will reduce the velocity of the water and enable particles to settle within the screens and be removed in a controlled way, instead of being flushed out to the lake.
The constructed wetlands were put in place in the summer of 2020. They provide a curtain of roots that also reduces the velocity of the water. Additionally, the roots absorb dissolved pollutions and make a pleasant scenery, integrated in the beautiful surroundings.
Impact and lessons learnt
The project in Arvika attracted a lot of attention from the media: there were regional reports on tv, radio and in newspapers. It also provided some important lessons. One of them is the need to take time consuming permit and procurement procedures into account when planning a project like this. Otherwise, they may cause an unforeseen setback in carrying out the project and thus in environmental gains. Timely dialogues and good relationships with stakeholders also contribute to the success of a project like this.
Last but not least, self assessment indicators have evoked the knowledge and awareness of the water challenges within our organization. The self assessment instrument, the Adapt My City tool, developed within CATCH, may prove useful for other cities as well.
Watch projectleader Josefin Andersson explain the pilot within 2,5 minutes.
If you wish to learn more about the water quality improvement project in Arvika, please contact us. Download our folder and poster here.
Visit the Arvika pilot project webpage (only in Swedish) on the website of the municipality of Arvika.
(The picture shows an example of constructed wetlands and screens from another city in Sweden).