Mitigating eutrophication in Himmerfjärden, Sweden traditional and recent stakeholder engagement

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1 Mitigating eutrophication in Himmerfjärden, Sweden traditional and recent stakeholder engagement SPICOSA Forum Brest, October 2008 Jakob Walve Science and Policy Integration for COastal Systems Assessment

2 Himmerfjärden a long tradition of stakeholder engagement SPICOSA may contribute to - continued engagement with the goals of the WFD in focus - integration of different policy options for eutrophication mitigation - integrating science in the WFD process SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

3 SSA 4 - Himmerfjärden

4 Mean depth: 17 m Salinity: 4 7 Forest, farmland and lakes in drainage basin Reference area 10 km

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7 Moraån Fitunaån Trosa river Reference area Discharge from rivers 10 kmand brooks (10 m 3 /s)

8 Lake Mälaren discharge (7 m 3 /s) through locks in city of Södertälje Mean depth: 17 m Salinity: 4-7 Brooks and diffuse runoff: 10 m3/s L. Mälaren: 7 m3/s STP: 1.5 m3/s Reference area 10 km

9 Lake Mälaren outlet Mean depth: 17 m Salinity: 4-7 Brooks and diffuse runoff: 10 m3/s L. Mälaren: 7 m3/s STP: 1.5 m3/s Reference area Major sewage treatment plant (STP) serving people, mainly living in southern Stockholm, outside the drainage basin 10 km (1.5 m 3 /s)

10 Eutrophication-related problems Turbid water due to high phytoplankton abundance Oxygen deficiency in deep water Loss of perennial macro-algae and increased biomass of annual algae

11 Totalfosfor, Phosphorus ton år -1 Discharge of nitrogen and phosphorus (tons/year) Utsläpp från Himmerfjärdsverket TP TN Totalkväve, Nitrogen ton år -1 From 1998 very efficient N removal is possible (90-95% reduction, to 4 mg/l) through fluidized bed technique for enhanced denitrification, with relatively low investment costs

12 Currently the enhanced N removal in STP is shut down for two years to show response of a Baltic estuary to increased N loading

13 Himmerfjärden has been intensively studied since the construction of the STP in the 1970 ies - Water quality monitoring and associated research

14 Traditional Stakeholder engagement for Himmerfjärden Dept. of Systems Ecology, Stockholm university monitoring and research (Ulf Larsson, Ragnar Elmgren) Himmerfjärden STP company (SYVAB) sees monitoring as valuable impact assessment, sincere willingness to reduce impacts Swedish EPA adoption of Himmerfjärden for experimental ecosystem-scale eutrophication research, e.g. to provide evidence in the nitrogen vs. phosphorus reduction debate Himmerfjärden nature protection society first much against exploitation, but due to willingness of STP company to work for better environment, further discussions have been constructive (Farmers- General regional projects for reducing nutrient emissions)

15 The objective of Spicosa, to develop a system approach framework, with stakeholder participation, has much in common with the WFD s vision of stakeholder participation in management plans WFD River basin planning cycle

16 First Spicosa stakeholder meeting in November was organized as a part of the WFD stakeholder meeting held by the regional water authority. Policy issue = eutrophication manifested as high algal biomass

17 A representative group of stakeholders was recruited for the SPICOSA project Participant Göran Andersson Carl Rolff Bo Ljungberg Ronald Bergman Dan Arvidsson Anders Forsberg Magnus Dybeck Robert Sehlén Jan Bosander Bertil Svangren Carl Bonde Per Pettersson Stakeholder organization County Board of Stockholm/ Water authority County Board of Stockholm Regional authorities Södertälje municipality Södertälje municipality Botkyrka municipality Local communities Botkyrka municipality Nynäshamn municipality Astra Zeneca (pharmaceutical industry) Companies Himmerfjärden STP company Himmerfjärden Nature Protection Society NGO Estate manager of Hörningsholm domain Local department of LRF the Federation of Swedish Farmers Farmers SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

18 SPICOSA may be model for stakeholder participation - With SPICOSA follow-up meetings (2 nd in spring 2008 discussed policy options, 3 rd will be in November 2008), the SPICOSA project will contribute to the continued engagement of the stakeholders and - will serve as an example for the Water Authority how to identify cost-effective ways to mitigate eutrophication (with scientific back-up) SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

19 Our objectives -We will identify a cost-effective mix of measures to reduce nutrient loads from the major STP, agriculture and private sewers, in order to achieve a reduction in phytoplankton biomass and an increase in water transparency. - Estimate the recreational benefits of an improved water quality. SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

20 SPICOSA may also contribute to an open-minded search for solutions Example is long pipe solution (still with effective treatment) which would reduce loads significantly on Himmerfjärden SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

21 Himmerfjärden a long tradition of stakeholder engagement SPICOSA may contribute to - continued engagement with the goals of the WFD in focus - integration of different policy options for eutrophication mitigation - integrating science in the WFD process SPICOSA Forum Brest, October 2008 Science and Policy Integration for COastal Systems Assessment

22 Thank you for your attention!

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25 SCENARIOS TO BE TESTED WITH THE SPICOSA MODEL SYSTEM Himmerfjärden Sewage Treatment Plant (HSTP) A B. Nitrogen (N) in discharge from HSTP reduced to 10 or 4 mg nitrogen per liter. C D. HSTP discharge point moved to top of summer thermocline and N reduction to 10 or 4 mg /L. E. HSTP discharge point moved to an outfall in the open sea south of Himmerfjärden and full N reduction (to 4 mg/l). Other measures F. Reduced agricultural nutrient leakage and more wetland creation in the drainage basin (several scenarios) G. Reduced nutrient emissions from private sewers and small sewage treatment plants in the drainage basin (several scenarios) H. Reduction of open sea nutrient concentrations according to the recently agreed HELCOM action plan.

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