Green Centre Essen Redesign of a park on an industrial brownfield site in the centre of the city of Essen

The "Universitätsviertel Essen" is being developed on a site of a former freight station in Essen's city centre that has been derelict for almost 30 years. The revitalization of this approximately 13-hectare site is currently creating the "Universitätsviertel - grüne mitte Essen", an urban quarter for living, living and working, which is being marketed under the slogan "Living. In the middle of the city". The central park in the centre of this new quarter between the city centre, the Limbecker Platz shopping centre and the university campus is the first visible building block of this development and therefore decisively shapes the new identity of the quarter.

Inspired by the history of the Segeroth quarter as the residential location of the Krupp foundry workers, the technical framework of casting technology is used to develop this design language. It can be found in all park elements from the ground plan to the details of the furniture. The central element of the park is the slightly elevated promenade with its recreational, play and sports facilities between the northern water park and the southern meadow park. It defines the central public and easily visible action area at a sufficient distance from the adjacent residential development.

A central north-south axis connects the University of Essen to the park and the city centre via the future central library.

Strategy for the development of the design concept

Innovative concepts for the design of parks have always responded to the prevailing living situation. Throughout history, these parks have usually been idealized counter-worlds to real life environments. For example, in the 18th century, people experienced dramatic landscape destruction due to the onset of industrialization and developed parks in the style of an idealized Arcadian world. In the 21st century, we are witnessing the dissolution of boundaries between nature and technology through genetic engineering; at the same time, biological design principles are being imitated in engineering techniques through bionics. This indifference between nature and technology forms the inspiration for the landscape architectural design of the University Quarter. Based on the history of the quarter as a residential location for the Krupp foundry workers, the technical framework conditions of the casting technique (corner radii, formation of slopes and intersections without right angles, non-additive shaping, etc.) are used to develop an independent formal language. This formal language as well as the metaphor of an integrative "park machine" can be found in all park elements from the ground plan to the details of the furnishing, thus creating the desired uniqueness of the entire park.

Space creation through central promenade

The urban design figure specifies a very long, narrow and radial footprint within the immediately adjacent residential and service construction fields for the realization of the park. Due to this particular basic form, the desired water areas and diverse recreational uses, as well as the expected high frequency of use of the inner-city park, one of the central design statements lies in the placement of offerings and pathway relationships. To reduce potential conflicts between residents and park users, subordinate paths are offered along the edges so that the semi-public character predominates here. The main path connection as well as the recreation, play and sports facilities are placed along a promenade in the open centre of the park. This has, besides the reduced noise pollution of the residents, the basic advantage of the possibility of a central, well visible public promenade between the northern water and the southern meadow park. In order to increase the spatial attractiveness of the promenade, it will not be carried out on one axis, but will be offset from the axis several times. In the area of the offsets, the promenade locations are placed as target points. The band of water basins is also oriented towards the promenade with a flat accessible bank as an attractive park element and thus strengthens the public centre of the complex. The central promenade is linked to the surrounding construction areas by numerous crossways through the meadows and footbridges over the water basins. At the intersection of the promenade with the pedestrian path axis University-City Centre there is an open, multifunctional event area with a large flight of steps.

Functional spaces and special parking areas

In accordance with the existing footprint, the functional allocation of the subspaces represents a decreasing noise level from Berliner Platz to Viehofer Platz. The prelude at Berliner Platz is defined by an urban plaza. A loose grove of ornamental fruit trees forms the transition to the park, which lies approx. 3.00 m lower. Between this grove and the central event area lies the intensively usable park section with its play and sunbathing areas as well as the promenade place "Parkplay". The adjoining park section up to Talstraße with its meadows and water areas as well as the promenade place "Parkgarden" rather serves the quiet recreation. In the last, very narrow park section up to Viehofer Platz, only seating is offered, which is also suitable for working in the shade of the trees in the area of the promenade place "Parklounge".

Precise choice of materials in the structural framework

In the design as well as in the choice of materials, the park is deliberately "technically" designed. The entire floor plan was developed in a curved construction grid, so that all visible edges and radii are very simply mathematically defined. The impression of the homogeneous mastic element was achieved by path surfaces, which are homogeneous mastic asphalt surfaces raised from the ground plane by means of sloping granite curbs. This design feature is echoed in the promenade locations, which are in turn raised from the path surfaces. The water and constructed wetlands are bordered with concrete elements and sealed with asphalt, although this is not just for design reasons. Due to the existing old industrial subsoil, the infiltration of rainwater is not possible on the entire site. The rainwater from the surrounding construction areas is discharged into the central water basins and temporarily stored. The water basins are continuously circulated by means of a central pumping system; in the process, the water is clarified both mechanically in an underground filter and biologically in the plant filter basins. The water level of the basins is kept constant within a level fluctuation range of 20 cm, and excess water is diverted into a neighbouring stream.

Differentiated plant images create emotional character

The spatial formation and character of the park is brought out through the differentiated use of plants with as little maintenance as possible. It stands in clear contrast to the technical fixtures and contributes decisively to the green character of the park, which is perceived very positively by the public. In order to achieve the greatest possible transparency and a corresponding sense of security, shrub plantings were consistently avoided. At Berliner Platz, existing plane trees form the entrance situation; the grove to the west of Berliner Platz is made up of conspicuously flowering ornamental cherries, apples and pears; the outer rows of trees in the east-west direction are formed by the Japanese cord tree; the promenade is accompanied by several tree magnolias; the places along the promenade are accentuated by solitaires (bluebell tree, amber tree, trumpet tree); the entrance to Viehofer Platz is again characterised by existing plane trees. Red maple avenues mark the axis between the university and the city centre. The northern park areas are characterised by planted filter basins with marsh species such as reeds and irises; in the southern park areas, a structured band of grass and shrubs filters the adjacent uses. Attractive splendid perennial and spring-flowering plantings accompany the central promenade at certain points.


Lighting concept for a high sense of security

Assuming that the two striking urban buildings at Berliner Platz and Viehofer Platz can take on the night-time landmark function for the park, a restrained lighting concept was developed from a security point of view due to the proximity to residential buildings. Analogous to the daytime situation, the central promenade should also be the main traffic area at night for noise protection and safety reasons. Accordingly, it will be brightly lit, the side paths somewhat darker, but still traffic-safe. The promenade locations will be staged using directional spotlights with different lighting angles, giving the spaces a stage-like character that will make them attractive locations at night.

Although the park and the surrounding high-rise buildings have not yet been completed in all construction phases, the park already represents a high-quality open space offer in the northern inner city of Essen, which is intensively used by residents, students and visitors.

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