Deliverable No. 14. 30/06/2018 (Action C2)
Summary
This report has been drafted by the Ecology group on behalf of Sollentuna Municipality and serves as a basis for the municipality’s water management planning. It has been produced within the LIFE IP Rich Waters project. Support has been granted by EU /LIFE and the Swedish Agency for Marine and Water Management for the purpose of developing methods and work approaches that can be also be applied by other municipalities for their water management planning.
Sollentuna Municipality is working to develop a water management plan that will take a holistic approach to the water issues in the municipality. Sollentuna is one of the first municipalities in the country to incorporate an ecosystem service perspective in the water management planning. The survey comprises ecosystem services associated with surface water and the relevant territories for rainwater management, flooding and other aspects of climate adaptation. The ecosystem services’ status and deficiencies have been analysed and serve as the basis for the recommendations for rectification work that have been provided in order to protect and strengthen the various services.
The report consists of two parts. Part 1 is a municipality-wide survey in which the relevant ecosystem services are described in text and on maps.
Part 2 describes the various ecosystem services collectively for the five sub-territories. The classification of areas is based on the sub-basins. Recommendations for corrective measures in order to preserve, strengthen and add relevant ecosystem services are provided for each sub-territory. The report ends with summarising conclusions and recommendations for rectification work.
The key conclusions of this report are:
- In large parts of the municipality there is good access to the areas that function well for the ecosystem services’ protection against flooding and water purification.
- The greatest deficiencies with respect to protection against flooding are in Sollentuna city centre/Tureberg and Rotebro. There are also smaller areas of deficiency in Kappetorp and Edsängen, among other places.
- There are deficient areas with respect to flooding from rising surface water primarily along Edsån and along the northwest part of Norrviken.
- The greatest deficiencies with respect to water purification are adjacent to Edsviken. Areas of deficiency are also located along Norrviken’s western shore, in Viby, in Edsberg and in Kärrdal/Sjöberg, among other places.
- Biodiversity is the ecosystem service exhibiting the greatest deficiencies. A major effort will be needed in order to achieve a good ecological status in areas such as Edsviken, Norrviken, Översjön, Fjäturen, Ravalen and Edsån. Past and current discharge of nutrients and pollutants impact the water quality negatively. Moreover, large portions of the areas near many lakes and water courses have been developed or are actively used, which worsens the conditions for biodiversity. At the same time, many lakes and water courses have high values for maintaining biodiversity, so rectification of the deficiencies has been prioritised.
- A significant portion of the catchment area (approx. 20 %) for the water bed in Stockholmsåsen consists of hardened surfaces. However, it is unclear how much that influences groundwater formation, especially in the northern part of the catchment area where the groundwater comes into contact with the surface water in Norrviken.
- There are currently six water course sections with known erosion problems. The majority of these lack natural erosion protection. There is also a number of water course sections that have been identified as being at risk of erosion. Some of these have natural erosion protection, but it is also lacking in areas adjacent to many of the risk sections.
- Deficiencies in functional border zones along many lakes and water courses impact several ecosystem services negatively: water purification, natural erosion protection and maintenance of biodiversity.
- The carbon cycle is an important ecosystem service that is related to, among other things, the water quality in lakes, coastal water and water courses. However, it has still not been established how exactly this relationship works, so it is difficult to incorporate this ecosystem service in the water management planning at the present.
- It has been assessed that there is great potential to strengthen ecosystem services related to water in Sollentuna Municipality within the scope of the water management planning.
