Sustainability concept
© moka-studio GbR
Sustainable city
Resource and climate protection as well as the adaptation to the consequences of climate change play a key role for Grasbrook due to its location on the Elbe island.
In addition to flood protection and an intelligent stormwater management, "green" architecture and energy supply are anchored in the planning at an early stage, as are future-proof infrastructure and communication technology.
Grasbrook is to become a model district for the reduction of resource consumption and CO2 emissions. To this end, the new buildings and new open spaces as well as the infrastructure and mobility must be designed to be as low-carbon as possible and later operated in a climate-neutral manner.
Reduction of CO2 emissions and resource requirements
Resource efficiency is to be achieved in the new buildings in particular by implementing circular construction methods. In addition to the buildings, the carbon footprint of structures such as bridges, riverbanks, promenades and roads will also be kept in mind. Transparent CO2 and resource management will help to identify optimization potential and reduce CO2 emissions.
The minimization of CO2 emissions in energy supply and mobility is equally important. For this reason, Grasbrook is consistently becoming a low-car district in which the environmental network of public transport, cycling and walking plays the central role in the mobility concept.
Valuable regenerative energies
Grasbrook is intended to help achieve the climate policy goals of the energy transition and Hamburg's climate plan. To this end, an intelligent and reliable energy supply is being developed that relies on CO2-neutral energy. As much of this as possible is to be generated locally – for example through environmental heat and photovoltaics on the roofs of houses and the large "roof". Additional requirements will be covered by public grids.
In order to use the valuable renewable energies as efficiently as possible, the buildings will have very low heating and cooling requirements thanks to high energy standards. They are connected to each other by a heating and cooling grid and are supplied with waste heat or environmental heat, for example.
Freshwater mudflats and ruderal vegetation at Moldauhafen © Thomas Hampel
Increasing ecological quality and biodiversity
Grasbrook is being built on an area that has been optimized for the port industry in recent decades. To this end, water areas were filled in to create large and almost completely sealed logistics areas, which were enclosed by quay walls and stone embankments. With the gradual decline in port use, however, nature was able to reclaim some areas. On disused freight tracks and silted-up areas in the Moldauhafen and Saalehafen with their valuable freshwater mudflats, riverbank fringes with various forms of spontaneous vegetation have developed.
The new Grasbrook district builds on what already exists, unseals large areas and creates new parks and green spaces. It leaves the water areas intact and creates new connections to the water by partially removing the quay walls. Existing ecological qualities are to be preserved and expanded in order to promote an increase in biodiversity in urban areas. The green streets and buildings with their green roofs and façades also contribute to this.
"Sponge City": intelligent integration of water cycles
Climate change impacts such as extreme weather and heavy rainfall events, heat stress and drinking water shortages also play a role in the planning of Grasbrook. Decentralized and close-to-nature rainwater management is intended to ensure a sufficient water supply for the vegetation in the long term. The aim is to retain and store the valuable resource of rainwater, use it to irrigate the vegetation in the district and thus save drinking water.
Due to its dual waterfront location by the Elbe and the adjacent harbor basins Moldauhafen and Saalehafen, Grasbrook has no fundamental difficulties in preventing heavy rainfall events. Nevertheless, it is particularly important for the street trees and the large park and green areas that the rainwater remains in the water cycle on Grasbrook as far as possible and is not discharged into the Elbe.
Urban stormwater management © büro luchterhandt & partner
In addition to the green roofs and façades of the buildings, decentralized stormwater management also includes the green residential courtyards, in which rainwater is retained and stored above the mound level and used for irrigation on the construction sites. The drainage of the public street areas, especially on Grasbrook Boulevard, is carried out without traditional stormwater pipes. The rainwater is directed into the green strips planted with trees, seeps away and remains available in the existing soil layers to water the trees.
The concept of urban stormwater management thus follows the principles of Sponge City: rainwater is gathered, stored and released again as required. This makes it possible to dispense with sieve systems with pipes, shafts and discharge structures. In addition, the aim is to use graywater to save drinking water in building services.
Urban development
The center around the Moldauhafen connects the two quarters of the district, the Moldauhafenquartier with a residential focus and the commercially characterized Hafentorquartier
Open spaces
A large park in the middle of the district, squares, promenades and wild green riverside zones create a variety of open space qualities
Uses
A district for everyone is being created in Grasbrook, with apartments, workplaces and many cultural, educational and leisure facilities
Mobility
A new subway station and a dense network of pedestrian and cycle paths make the use of private cars superfluous in Grasbrook