DNV-Gødstrup, the new hospital for western Denmark, will be built close to the city of Herning up to the year 2020. As a step in the Region's Agenda 21 Strategy and Action Plan 2012-15, the concepts of sustainability, low energy consumption and little environmental impact must be incorporated into planning the hospital project. Since the beginning of the construction process, part of the plan has been that the hospital is to be designed and built according to the DGNB sustainability certification scheme. Drinking Water Demand and Waste Water Volume is an important criterion in this system.
"Sustainable development is being afforded much attention from many corners of society.At Central Denmark Region we are aware of our responsibility in this regard.We want development - development towards more sustainability," said Bent Hansen, Regional Council Chairman in Central Denmark Region and Chairman of Danish Regions.
To fulfil these political wishes, the full-service consultant on the building project, the CuraVita consortium, incorporated sustainability and natural surface water and rainwater diversion as a central element of the project in its overall plan for the hospital. Planning of the project was a collaborative effort between the full-service consultant, the project secretariat and the Municipality of Herning, which approved all proposals.
According to CuraVita, in many ways, rainwater diversion will constitute the keystone of the hospital's landscape design. The rainwater will be diverted via troughs from roof surfaces, parking surfaces, paved courtyards and ground surfaces onto interconnected basins south and north of the buildings, and from here onwards via spillways to the Herningholm Å watercourse outside the hospital's property. These retention basins and the remaining design of surface area on the property have the capacity to receive and manage massive volumes of rainwater: a total volume of around 14,000 cubic metres, which will be managed and retained even during extreme water levels, e.g. in connection with cloudburst events, making sure hospital operations can continue without interruption. From the hospital parking places, surface water will be diverted to troughs that are designed to allow as much as possible of the water to seep down into the ground, while the rest is led onwards as described above.
The plan is that all rainwater will either percolate down through the ground or will be led away across the surface to the Herningholm Å watercourse, so that the public sewer system is not overloaded. However, local soil conditions throughout major parts of the area around the hospital site make percolation difficult. A combined solution will therefore be established, in which as much percolation as possible will take place in the northeastern part of the site where percolation is possible, while the remainder of surface water will be evenly distributed before it is discharged to Herningholm Å. This is to ensure that watercourses in the local area are not overloaded potentially causing flooding and erosion.
"This project is enormous and may have huge impacts on surrounding water systems.We try to find holistic solutions that will allow us to build something this big without destroying any of the existing features of the area," said Bent Hansen.
The illustration shows that the troughs will have enough capacity to cope even with extreme water levels. Like the remainder of the rainwater diversion solutions, the troughs will moreover be incorporated as a natural part of the hospital's recreational areas. As illustrated, the troughs will therefore be level with footpaths, cycle paths and vegetation.
Sustainability is also about aesthetic aspects and social wellbeing. In accordance with the DGNB system, outdoor areas must be designed so that they contribute positively to the building and its adjoining areas. The retention basins will therefore be constructed as wetlands, resembling the small natural lakes that used to be a characteristic feature of the landscape. The northern embankments of the lakes will be planted with indigenous, water-tolerant trees such as common alder, willow and birch, just as the water table in both basins will be situated as high as possible; all of which is to enhance the recreational value of the area. Management of surface water and rainwater will therefore be an important part of the vision of a holistic architectural design in coherence with paths etc.
"The hospital's vision explicitly mentions that the hospital is to ensure the wellbeing of patients and employees by being founded on an evidence-based design, healing architecture and sustainable solutions.Exploiting rainwater in this way efficiently and holistically realises both the vision of a 'hospital for patients', as well as Central Denmark Region's Agenda 21 targets," said Bent Hansen
Retention basins and troughs will be an integral part of the recreational areas of the DNV-Gødstrup hospital.This will make the recreational areas an important part of the healing architecture of the hospital; an architecture that is to provide the optimal physical framework for patients and staff.