AstrA

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AstrA

• Case study areas Cities Kokkola and Raahe
• 18-20. May 2006
• Klaipeda
• Satu Putkinen, GTK Finland

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Case Study areas
Bothnian Bay

• City of Kokkola
• City of Raahe

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Case Kokkola

• Main interests are the impacts on
• 1.Harbours
• 2.Industrial sewage water plant
• 4.municipal sewage water plant
• 5.Rummelö Natura 2000 area
• 6.Planned Sea Kokkola residential area
• 7.River Sunti planning
• 8.Bride Island residential area
• 9.Trullevi recreational buildings
• 10.Boat harbours
• 11.Recreation areas on shoreline
• 12.Dredgings of boating routes and shores
• 13.Wind energy building
• 14.Water quality changes of the seawater

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The aims of City of Kokkola

• Description of the most probable/worst scenarios
  (sea level rise, storms, irregular weather
  events, droughts, precipitation, flow rates of
  the rivers).
• To describe the development alternatives of the
  Old Harbour Bay and surroundings as well as the
  Ykspihlaja industry area in different scenarios
  till year 2100.
• How these results can be taken into account in
  city planning WP3 documentation of the
  planning and related communication processes.

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Historical rewiew - future
Shore line changes 1500-1800

• Collecting of the data of shore line changes and
  land use 500 years back (maps and physical
  changes on environment)
• Estimating shore line changes till year 2100 in
  different scenarios

1800
1700
Kokkola, founded 1620
1600
1500
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Kokkola sea level change
DRAFT VERSION

• High case
• 10 cm
• Ensemble average
• -41 cm
• Low case
• -87 cm

Draft version
The lowest allowed height of building Kokkola
2.20m, Raahe 1.50m
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The City of Kokkola

• In 1980ies storm surge cause flooding in River
  Sunti water level reached Market place 2
  kilometers from sea-shore.
• Water level changes happen in few hours during
  the storms
• Highest water level in November (1.2 meters
  above normal) critical time for storms if no
  ice cover.
• Usually ice cover between December and April

Draft version
Draft version
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Ykspihlaja area in Kokkola

• Heavy industrial area
• Sewage treatment plant near sea
• Industrial waste water reservoir 3 m a.s.l.
• Natura - protection area

Draft version
Draft version
Draft version
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Impacts on leisure time

• Summer cottages by the sea shore
• Boating changing routes
• Skiing, skating
• Icehole fishing

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The lowest recommendable height for building

• Including the minimum wave action
• Source Kahma et al. 1998

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The City of Raahe

• Old housing and summer cottage area on low-lying
  seashore
• Boat routes are in danger
• There is model of sea-level changes for harbour
  done before
• Effects on coastal nature

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The City of Raahe

• Ideal coast for wind mill park low coast, small
  islands to shelter the mills gt Problems in
  future? Storm winds? Advantages? Best locations?
• How will the the currents in Bothnian Bay change
  in future?
• Rivers bring sand and other debris with nutrients
  to shore gtgt problems with algae in closed bays
• Moving underwater sandbanks cause problems in
  coastal area. Erosion sandy beaches turn out to
  stony
• Ice cover changes? No ice at the winters? More
  heap pack ice? Will the ice masses pack into the
  coasts more often? Can extend 600 m on-shore
  causing destruction! How to prepare for that?

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The City of Raahe

• Heavy industrial area is near the shore. (metal)
• Port of Kokkola is one of the busiest (6)
• Open year round
• 700 ships / year
• Route to be dredged 2007-2008 (10 meters deep)

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Thank you!

• Satu Putkinen
• Western Finland Office, GTK
• Tel. [phone]
• Mobile [phone]
• Email satu.putkinen_at_gtk.fi