1. Sustainable management of the storm water treatment system for Latvia Municipalities Experience from Malmo City on management of storm water Dr Annika Kruuse af Verchou Åsa Abrahamsson

2. Sustainable management of the storm water treatment system for Latvia Municipalities

3. Historic development of storm water management in Malmö Open systems Piped, combined systems Piped, separated systems Open systems – reinvented

4. Sustainable management of the storm water treatment system for Latvia Municipalities Principles of ecological storm water management Retaining and infiltrating close to the source Slow run-off Retaining further away from the source Local management

5. Sustainable management of the storm water treatment system for Latvia Municipalities Categories of open storm water solutions Private land Public land

6. Sustainable management of the storm water treatment system for Latvia Municipalities Advantages of ecological storm water management Less expensive construction Management Decreased risk for local flooding. No risk of overflow in water treatment plant Attractive housing area or city, higher prices Signposts declaring: modern, environmentally thinking Storm water is cleaned

7. Sustainable management of the storm water treatment system for Latvia Municipalities Advantages (cont.) Hydrological balance Biodiversity enhanced Pedagogical gain Aesthetical values Adds the element of water to green areas Waste is naturally collected in the ditches

8. Sustainable management of the storm water treatment system for Latvia Municipalities

9. Housing district Western Harbour in Malmö European housing expo ”Bo01” in 2001 25 ha, 559 housing units by spring 2003 Environmental measures: energy, waste, buildings, mobility, green and blue

10. Sustainable management of the storm water treatment system for Latvia Municipalities Courtyards, streets, and squares Miniature canals Ponds with or without vegetation Green roofs, green space factor Storm water system

11. Sustainable management of the storm water treatment system for Latvia Municipalities

13. vegetation, open water1 green roofs0.8 green walls0.7 semi-permeable0.4 non-permeable0 Green space factor

14. Sustainable management of the storm water treatment system for Latvia Municipalities House, other non-permeable 500m 2 Vegetation, open water 300m 2 Semi- permable 200m 2 Green space factor Total area 1 000m 2 House, other non- permeable : 0 Semi-permeable: 0.4 Vegetation, open water : 1 GSF= (500x0 + 300x1+ 200x0.4)/1000 = 0.38 Minimum level for Western Harbour: 0.5

15. Sustainable management of the storm water treatment system for Latvia Municipalities Housing area Augustenborg, Malmö Built in the 1950s Renovated during the 1990s

16. Sustainable management of the storm water treatment system for Latvia Municipalities Storm water system of Augustenborg Two parts –concrete canals, open ditches Almost one pond for each building Green roofs Final retaining pond in the park

17. Sustainable management of the storm water treatment system for Latvia Municipalities

19. Green parking places

20. Sustainable management of the storm water treatment system for Latvia Municipalities Important features of storm water system in Cēsis and Jelgava Existing, well functioning open storm water systems Experience and knowledge of building and managing open systems

21. Sustainable management of the storm water treatment system for Latvia Municipalities Recommendations for the future Put demands on developers as regards storm water management The demands could be organized as a green space factor The planning should come in early in territorial planning processes Planned together with other physical aspects Don’t repeat the mistakes of Malmo, keep and develop the open systems

22. Sustainable management of the storm water treatment system for Latvia Municipalities Thank you for your attention