1. General information
Location and description of the intervention
City or FUA
Stockholm
Region
Europe
Native title of the NBS intervention
Projekt Slussen – Ny reglering av Mälaren
Short description of the intervention
‘Slussen and a new water regulation plan for Lake Mälaren’ is part of the rebuilding of the city district Slussen (The Slussen Project) (Ref. 1). In connection with the rebuilding of Slussen, SMHI (Swedish Meteorological and Hydrological Institute) was in 2007 commissioned by Stockholm City to review and propose a new regulatory strategy for the lake Mälaren (Ref. 2). A new regulation prevents floods, reducing the risk of saltwater entering the lake, benefiting the natural environment around Mälaren. Further effects will also benefit the ecosystem of the lake (Ref. 3).


Address

Slussen
Stockholm
Sweden

Location
The NBS is a city-wide initiative, the GIS point marks the centre of the city
Type of area before implementation of the NBS
Central Business District / City Centre
Website of the intervention
http://vaxer.stockholm.se/projekt/slussen/slussen-klimatanpassas/
Timeline of intervention
Start date of the intervention (planning process)
2007
Start date of intervention (implementation process)
2015
End date of the intervention
ongoing
Present stage of the intervention
Ongoing
Please specify "other" stage of the intervention
In 2007, SMHI (Swedish Meteorological and Hydrological Institute) was commissioned by Stockholm City to review and propose a new regulatory strategy. In 2015 (20th of August) the city received permition under the national environmental laws (Miljöbalken) to rebuild Slussen and regulate Lake Mälaren. (Ref 2, 3)
Goals of the intervention
"One of the overall goals of the proposed regulatory proposal is that it will create water-level variations that benefit the beach-based natural environment. This means that both low and high water levels shall be allowed to occur." (Ref. 4)
The new regulation of the Mälaren aims to:
1. Reduce the risk of flooding around Lake Mälaren;
Social interests: Drinking water supply, buildings and infrastructure, shipping, agriculture.
2. Reduce the risk of low water levels in Mälaren;
Social interests: Drinking water supply and shipping
3. Prevent saltwater intrusion;
Social interests: Drinking water supply.

Also takes into account valuable beach-based natural environments by striving for seasonal variations that favour the beach-based natural environment. (Ref. 4)
Quantitative targets
Increased water flow capacity in Söderström to approximately 1400 m3/s and an expansion of Hammarby's capacity from 70m3/s to 140m3/s. (Ref. 4)
Monitoring indicators defined
water flow capacity (ref 4)
Sustainability challenge(s) addressed
Climate action for adaptation, resilience and mitigation (SDG 13)
Climate change adaptation
Water management (SDG 6)
Flood protection
Green space, habitats and biodiversity (SDG 15)
Green space creation and/or management
Health and well-being (SDG 3)
Creation of opportunities for recreation
Climate change adaptation: What were the goals of the NBS?
Build resilience
Climate change adaptation: What activities are implemented to realize the conservation goals and targets?
Renaturalization of rivers and other water bodies
Implementation activities
"Forming the central junction between north and south Stockholm, Slussen is a strategic infrastructure asset with regard to transport, clean water provision and flood protection for Stockholm and the Mälardalen region. [The Slussen lock] acts as one of the gates between freshwater (Mälaren) and saltwater areas (Baltic Sea), thereby playing a key role in the provision of clean water...The development also includes new green and commercial spaces to make the lock more attractive to locals and visitors." (Ref 14)
Type of NBS project
Management and improved protection of rivers and other blue areas
Strategy, plan or policy development
NBS domain and interventions
Ecological domain(s) where the NBS intervention(s) is/are implemented
Blue infrastructure
Lakes/ponds
Coastlines
Amenities offered by the NBS
Unknown
Services
Expected ecosystem services delivered
Provisioning services
Water (surface and ground water for drinking and non-drinking purposes)
Regulating services
Flood regulation
Water purification / filtration
Scale
Spatial scale
Micro-scale: District/neighbourhood level
Beneficiaries
Primary Beneficiaries
Local government/Municipality
Private sector/Corporate/Company
Citizens or community groups
Governance
Governance arrangements
Co-governance with government and non-government actors
Non-government actors
Public sector institution (e.g. school or hospital)
Private sector/Corporate/Business
Citizens or community groups
Please specify the roles of the specific government and non-government actor groups involved in the initiative
The City of Stockholm commissioned SMHI (Swedish Meteorological and Hydrological Institute) to propose new regulations. (Ref 2)
Structor Miljöbyrån has led the work on the permit application on behalf of the City of Stockholm. (Ref. 6)
Citizen dialogues have been included in the Slussen project. (Ref. 7)
“The city of Stockholm owns, manages and utilizes Slussen. The city of Stockholm usually does not act as contractors/developers in major infrastructure projects, but leaves this to developers. The Traffic Office manages the current Slussen and will also be the recipient of the project's deliveries.” (Ref 8)
Key actors - initiating organization
Local government/municipality
Land owners
Public space owned by the city
Key actors - Other stakeholders involved (besides initiating actors)
National government
Local government/municipality
Private sector/corporate actor/company
Land owners
Public space owned by the city
Participatory methods/forms of community involvement used
Taskforce groups
Policy drivers
NBS intervention implemented in response to an Regional Directive/Strategy
No
Please specify the "Regional Directive/Strategy"
The City of Stockholm commissioned SMHI (Swedish Meteorological and Hydrological Institute) to propose new regulations. (Ref 2)
NBS intervention implemented in response to a national regulations/strategy/plan
Unknown
NBS intervention implemented in response to a local regulation/strategy/plan
Yes
Please specify the "local regulation/strategy/plan"
The intervention is part of the Slussen project (rebuilding of Slussen/New Slussen). (Ref. 3)
The Slussen project is a water regulation strategy. (Ref. 4)
Mandatory or voluntary intervention
Voluntary (spontaneous)
Enablers
Presence of specific city-level GI/NBS vision/strategy/plan - mentioned in connection to the project
Unknown
Presence of specific city-level GI/NBS section/part in a more general plan - mentioned in connection to the project
Yes
Please specify the general plan with GI/NBS section
The whole slussen project is included in the 'Vision 2030 - A world-class city' (The city of Stockholm) (Ref. 10, 15)
If there is a relevant strategy or plan, please specify the theme / type of the plan.
Water regulation strategy
General municipal plan
Presence of city network or regional partnerships focused on NBS - mentioned in connection to the project
Yes
Please specify
“The rebuilding of Slussen has also been raised as an example in Europe. EU Mayors Adapt was established in 2014 by the EU Commission to engage the cities to work more focused to adapt to climate change. The aim of the initiative is also to create more discussions on climate issues. The city of Stockholm joined the initiative in 2014 and some goals with the EU Mayors Adapt are to create an opportunity for information exchange, support each other and develop concrete measures against climate change.” (Ref. 3)
Presence of GI / NBS research project - mentioned in connection to the project
Yes
Please specify
The regional government (Stockholms län) has developed a paper on climate changes and the Lake Mälaren from a water and natural environment perspective to support and facilitate adaptation work to a changing climate. (Ref. 9)
Subsidies/investment for GI / NBS in the city - mentioned in connection to the project
Unknown
Co-finance for NBS
Unknown
Co-financing governance arrangements
Unknown
Was this co-governance arrangement already in place, or was it set up specifically for this NBS?
Unknown
Financing
Total cost
More than €4,000,000
What is/was the Cost/Budget (EUR) of the NBS or green infrastructure elements?
90 million euro
What are the total amount of expected annual maintenance costs?
Unknown
What is the expected annual maintenance costs of the NBS or GI elements?
Unknown
Please specify cost savings
Unknown
Please specify total cost (EUR)
The total cost is estimated to 90 million euro (900 million SEK), and the total socio-economic value is around 1.5 billion euro (15 billion SEK). (Ref. 11)
Source(s) of funding
Public local authority budget
Other
Please specify other source of funding
Responsible for the funding: municipalities (23 coastal municipalities and 28 municipalities taking their water from Lake Mälaren) and the transport administration (state actor). (Ref. 11)
Type of fund(s) used
Earmarked public budget
Non-financial contribution
Unknown
Business models
Risk reduction model
Urban offsetting model (biodiversity or water)
Which of the involved actors was motivated by this model?
Public actor (e.g. municipality)
Type of innovation
Social
Policy innovation
Please specify social innovation
A new regulatory strategy for the Mälaren is being tested and proposed, which is also adapted to requirements and wishes from different sectors of society. (Ref. 4)
Novelty level of the innovation
The innovation is copied/derived from previous initiative(s) with substantial adaptation
Please specify novelty level of the innovation
The intervention builds on previous regulations for Mälaren (from 1941 and also 1966), but the new regulations are modified/differ from the previous. (Ref. 4).
Replicability/Transferability
Ambiguous (e.g. multiple interpretations)
Please specify Replicability/Transferability
“The rebuilding of Slussen has also been raised as an example in Europe. EU Mayors Adapt was established in 2014 by the EU Commission to engage the cities to work more focused to adapt to climate change. The aim of the initiative is also to create more discussions on climate issues. The city of Stockholm joined the initiative in 2014 and some goals with the EU Mayors Adapt are to create an opportunity for information exchange, support each other and develop concrete measures against climate change.” (Ref. 3)
Impacts, benefits
Environmental impacts
Climate change
Increased protection against sea level rise
Strengthened capacity to address climate hazards/natural disasters
Water management and blue areas
Improved water quality
Increased protection against flooding
Green space and habitat
Increased green space area
Please specify other economic impact
Value of the produced socio-economic benefits around Lake Mälaren (Ref. 5)
Description of environmental benefits
- The project essentially regulates the flow between freshwater and saltwater leading to improved drinking water quality through a lock system. The locks are also useful for flood management as floods are expected to get exacerbated due to climate change. The project area is also converted into a green space. (Ref 14, 15)
- "Forming the central junction between north and south Stockholm, Slussen is a strategic infrastructure asset with regard to transport, clean water provision and flood protection for Stockholm and the Mälardalen region. [The Slussen lock] acts as one of the gates between freshwater (Mälaren) and saltwater areas (Baltic Sea), thereby playing a key role in the provision of clean water...The development also includes new green and commercial spaces to make the lock more attractive to locals and visitors." (Ref 14)
- "[The Project] will eliminate the present risk of flooding, as well as allowing for an increase in sea level caused by future climate change" (Ref 15)
- Two alternatives for Lake Mälaren are compared, the 'Zero option' (the current regulation) and the 'Main option' (the proposed future regulation). “The increased capacity (the Main option) provides good opportunities to handle both the current and the future's extreme inflow. This means that the risk of flooding is largely eliminated in the 2050-2100 time perspective.” (Ref. 4)
- Also, Mälaren provides around 2 million people with water. (Ref. 11)
Economic impacts
Other
Description of economic benefits
Furthermore, the estimated total value for the produced socio-economic benefit around Lake Mälaren is 127 billion SEK (12,7 billion euro). (Ref. 5)
Social and cultural impacts
Unknown
Description of social and cultural benefits
Unknown
Type of reported impacts
Expected impacts
Achieved impacts
Indicators
1. Number of days with high water( Ref. 4);
2. Water Provision (Ref. 11);
3. Value of the produced socio-economic benefits around Lake Mälaren (Ref. 5).
Environmental, social and economic impacts
Climate action for adaptation, resilience and mitigation (SDG 13)
Coastal resilience and marine protection (SDG 14)
Green space, habitats and biodiversity (SDG 15)
Health and well-being (SDG 3)
Water management (SDG 6)
Analysis of specific impact categories
Job creation: The NBS created ...
No information available
Negative impacts: Did the project cause any problems or concerns?
No information was found regarding negative impacts of the project
COVID-19 pandemic
Unknown as of August of 2020
Methods of impact monitoring
Process of recording NBS impacts
No evidence in public records
Methods used to evaluate the impacts of NBS
Measurements of biophysical aspects of the NBS (e.g. temperature, water flow)
Evidence for use of assessment
Presence of an assessment, evaluation and/or monitoring process
Yes
Presence of indicators used in reporting
Yes
Presence of monitoring/evaluation reports
Yes
Link to monitoring/evaluation reports
http://www.structor.se/slussen/Ansokningshandlingar/Forslag_till_ny_reglering_a…
Availability of a web-based monitoring tool
No evidence in public records
Impact assessment mechanism
Name of any specific impact assessment tools
Environmental impact assessments (sv. Miljökonsekvensbeskrivningar) e.g. Projekt Slussen - Natura 2000: Miljökonsekvensbeskrivning av ny reglering av Mälaren, and Projekt Slussen - Ny reglering av Mälaren: konsekvensbedömning av strandnära naturmiljön. (Ref 12, 13)

Link to the output of assessments
http://www.structor.se/slussen/Ansokningshandlingar/Natura_2000.pdf
Use of GIS in mapping impacts
No evidence in public records
Citizen involvement
Citizens involvement in assessment/evaluation
Yes
Mode(s) of citizen involvement in evaluation/assessment
Other
Please specify other modes of citizen involvement in evaluation/assessment
Consultation meetings (sv. Samråd) and citizen dialogues (Ref. 4, 7).
In the first phase, SMHI made proposals for new regulations for Project Slussen for the consultation meeting in 2007 and based on comments from consultation meetings held in 2010, adjustments were made to the regulation. (Ref. 4)
Citizens involvement in the analysis of the assessment/evaluation
Yes
Please specify
Through citizen dialogues regarding detailed planning for project Slussen (Ref. 7)
Follow-up to the evaluation / assessment
Unknown
References
Web links relevant to the intervention
Ref. 1
Ref. 2
Ref. 3
Ref. 4
Ref. 5
Ref. 6
Ref. 7
Ref. 8
Ref. 9
Ref. 10
Ref. 11
Ref. 12
Ref. 13
List of references
Ref. 1. Stockholms Stad (n.d.) Översvämningsriskerna i Mälaren. Projekt Slussen. Information obtained: 2017-06-07. Source: http://vaxer.stockholm.se/projekt/slussen/slussen-klimatanpassas/ [Accessed 19 August 2020]
Ref. 2. Mälarens Vattenvårdsförbund (n.d.) Ombyggnation av Slussen. 2014-2017. Information obtained: 2017-06-07. Source: http://www.malaren.org/malaren/nyttjande-och-paverkan/fysisk-paverkan/ombyggnation-av-slussen/ [Accessed 19 August 2020]
Ref. 3. Stockholms Stad (2015) Slussen klimatanpassas - skapar intresse i Sverige och Europa. Source: https://translate.google.com/translate?sl=auto&tl=en&u=https%3A%2F%2Fvaxer.stockholm%2Fnyheter%2F2015%2F09%2Fslussen-klimatanpassas---skapar-intresse-i-sverige-och-europa%2F [Website updated on 1 October 2018. Accessed 19 August 2020]
Ref. 4. Andréasson, J., Gustavsson, H., & Bergström, S. (2011) Projekt Slussen - Förslag till ny reglering av Mälaren. Rapport nr 2011-64. SMHI. Source: https://ssps2.stockholm.se/anonym/slussen/Miljobalken/forslag_till_ny_reglering_Malaren.pdf [Accessed 19 August 2020]
Ref. 5. Löfmarck, A. & Svensson, M (2014) Samhällsekonomisk värdering av rent vatten: Fallstudier av Vombsjön och Mälaren. Rapport nr 2014-14. Svenskt Vatten Utveckling. Source: http://vav.griffel.net/filer/SVU-rapport_2014-14.pdf [Accessed 19 August 2020]
Ref. 6. Structor (n.d.) Dom i målet om Mälarens reglering: Stockholms Stad har fått tillstånd för Slussen och ny reglering av Mälaren. Information obtained: 2017-06-07. [Website not available in 2020]
Ref. 7. Stockholms Stad (2017) Dialogen med medborgare i projektet Nya Slussen, Nr 3. Stockholms Stad. [Website not available in 2020]
Ref. 8. Stockholms Stad (2016) Styrning av projektet Nya Slussen, Nr 5. Stockholms Stad. [Website not available in 2020]
Ref. 9. Länsstyrelsen Stockholms Län (2011) Klimatförändringar och Mälaren: ur ett vatten- och naturmiljöperspektiv. Anpassning till ett förändrat klimat. Rapport 2011:2. Source: https://www.lansstyrelsen.se/download/18.4771ab7716298ed82ba6eb9a/1526068282258/Rapport%202011-2%20Klimatförändringar%20och%20Mälaren.pdf [Accessed 19 August 2020]
Ref. 10. Stockholms Stad (2007) Vision 2030 - Ett Stockholm i världsklass. Stockholms Stad. Source: https://start.stockholm/om-stockholms-stad/stadens-vision/ [Updated on 7 January 2020. Accessed 19 August 2020]
Ref. 11. Skogö, I. (2012) Ansvarsfördelning och finansiering av Slussen i Stockholm. Mälarkonferensen. Regeringskansliet. Source: https://docplayer.se/1562522-Av-slussens-anpassning-ingemar-skogo-uppdraget-om-en-ny-reglering-av.html [Accessed 19 August 2020]
Ref. 12. Hebert, M. & Koffman, A. (2011) Utredning om konsekvenser på Natura 2000-områden. Projekt Slussen. Ny vattenreglering av Mälaren. Reglering version Fas 3c. Calluna AB, Stockholm. [Website not available in 2020]
Ref. 13. Calluna AB (2010) Projekt Slussen:Ny reglering av Mälaren:Konsekvensbedömning av strandnära naturmiljön. Sthlm. Source: https://docplayer.se/24681964-Projekt-slussen-ny-reglering-av-malaren-konsekvensbedomning-av-strandnara-naturmiljon.html [Accessed on 19 August 2020]
Comments and notes
Public Images
Photo of the lock and surrounding area built to regulate water in the city.
Stockhom Slussen Lake Mälaren
https://www.c40.org/case_studies/retrofitting-and-adapting-the-slussen-lock-stockholm-sweden