Creating flood plains and making the tidal Elbe experience possible
Pilot Project Kreetsand
Cities and Climate ChangeExperiencing the Island landscape
Elbe Islands Dyke Parkto the project
Pilot Project Kreetsand
The IBA Project Kreetsand, a pilot project in the framework of the Elbe tidal concept of the Hamburg Port Authority (HPA), will create additional space for the Elbe river on the east side of the Elbe island of Wilhelmsburg. The tidal volume will be enlarged and the tidal hub reduced as a result of these river engineering measures. At the same time, new possibilities for an integrative planning and implementation of a variety of interests and concerns relating to flood protection, use of the port, water management, nature conservation and recreation areas will be dealt with. In this situation the Kreetsand project will be presented as part of the IBA project Deichpark-Elbinsel. These aspects for the complete Elbe island will be analysed during the project and beneficial measures and strategies developed for the combination of the different requirements.
The „concept for the sustainable development of the tidal Elbe as a lifeline of the metropolis region Hamburg“ was developed in 2006 in the form of a joint venture by the Hamburg Port Authority and WSD Nord. The implementation of this concept is the prerequisite for the future viability of the Hamburg Port and demands a radical change of perspective in handling the tidal dynamic of the Elbe. In late summer 2010 the IBA Hamburg and the HPA were able to reach a quality agreement and qualify the undertaking as an IBA project.
Large sections of the Elbmarsch have been provided with dikes since the 12th century. Formerly to gain agricultural land and settlement areas; today usually to satisfy the demand for trans-shipment areas in the port. Since then there has been an increasingly reduced area available as flood plain and the sediment in the Elbe can only be deposited in a fractional area of what was once available. Natural changes such as the widening of the Elbe estuary also lead to an increase in tidal energy, and more sediment can be transported further upstream due to the stronger high-tide current. But because the low-tide current of the Elbe flows more slowly, it can no longer transport the sediment back to its former location. The constant change between high tide and low tide functions like a sediment pump. This effect, which is also known as „tidal-pumping", leads to an accumulation of sedimentation that must be dredged in the Hamburg Port and in the upper region of the tidal Elbe on a regular basis.
The creation of the Tidepark Kreetsand will enlarge the flood plain of the Elbe and consequently reduce the tidal hub. At the same time, the Hamburg Port will benefit from the reduction of the sedimentation and incidentally the risk of flooding will be diminished. In the course of the pilot project, the now de-embanked former flushing field Spandenlander Busch / Kreetsand will be deepened. In the 30 hectare shallow water area, the tide will be able to flow in and out freely – resulting in an additional tidal flow of around one million cubic metres.However, the pilot project is not planned merely as a purely hydraulic measure; it also takes the aspects of the quality of designing and landscaping as well as of nature conservation and recreational value into consideration.
A park with access to the newly created water areas and to the Elbe is planned as well as several open space planning designing measures. Small footbridges will guide the visitors over the water past the reeds and in this way open up an unobstructed view of the entire water area.
So-called „Deichbuden“ (dike huts) could serve as information and exhibition centres explaining the pilot project and the special features of the landscape with its functional, spatial and aesthetic associations of dikes, embankment foreland and hinterland. The Tidepark Kreetsand thus encourages the sensory experience of the water, the water dynamic and the tidal hub of the Elbe and makes a very special metrozone of Hamburg perceivable.
Information pavillon "Deichbude"
At the "Deichbude", an information pavillon directly located on a dyke, the Hamburg Port Authority (HPA), in a close cooperation with the international building exhibition (IBA) Hamburg and the Agency of Roads, Bridges and Water (LSBG), the complex connections and specialities are vividly illustrated in an exhibition. Hence, the "Deichbude" is a point of interest within the IBA-project "Elbe Islands Dyke Park" and for the pilotproject "Kreetsand".
Eastern Elbe Island Wilhelmsburg at Norderelbe, Kreetsander Hauptdeich