The canton wants to ensure that the centrally located and extremely well-connected site at Rosental Mitte is developed in the interests of the canton, the city and its economy. By purchasing the site, the canton wants to see the area opened up to the public and integrated into the city.

Rosental Mitte has already adapted in response to structural changes in the past and has transformed gradually from an industrial production site into an administrative and research location. The usage concept focuses on creating high-quality workspaces for high value-added industries and activities, such as company headquarters, high-quality corporate services and research facilities, which require a central, accessible, prominent location and a pleasant working environment. The canton aims to retain the existing companies and educational institutions on the site while also creating spaces for new companies and institutions to occupy. The urban development plan foresees potential for a further 3,000–5,000 jobs on top of the current 3,500 on the site. Whether or not this potential will be realised depends on the future market demand.

Rosental Mitte is intended to be not just a hive of business activity but also an attractive residential area, where the needs of the local population are met and they can enjoy a high quality of life. A differentiated range of housing with potential for 1,100–2,200 residents will include living spaces in a range of price brackets, ensuring a mix of social backgrounds. At least a third of the housing built will be affordable housing. Shops, restaurants, cafés and sports and leisure facilities will provide places for social interaction and bring life to the new pathways and green spaces. Urban life will not just go on at ground level, however, as there will also be public spaces on some of the rooftops. Commercial and cultural spaces will also contribute to the urban character of the new neighbourhood.

The opening of the site depends on a variety of technical and legal factors, and an exact date cannot yet be determined. The time line must be considered carefully, taking into account the legal requirements and the needs of the existing tenants and neighbours. Various inspections and discussions with the tenants are currently underway. What is known is that the site will open up from the outside edges in and in multiple stages. The first stages may be ready to open from 2021.

Under the canton’s structure plan, Rosental Mitte is considered a ‘work-focused’ site, so business use is the main focus. Creating housing and introducing services will help integrate the area into the existing Rosental district, resulting in an attractive, diverse, lively neighbourhood with a high quality of life. Creating more housing will also help relieve the pressure on the housing market and reduce commuter traffic by providing more residential options within the city.

A diverse range of housing is planned for the site, with potential for approximately 1,100–2,200 residents. The options range from cooperative housing to residences in the planned high-rise buildings, meaning there will be housing available in a range of price brackets. A third of the housing built will be affordable housing.

The long-term, step-by-step transformation of the site will take a number of years. During the transitional phase, affordable workspace will be on offer, while once the transformation is complete, high-quality, ready-to-rent workspace will be available. Interest has already been expressed in both. Discussions are underway with the tenants who currently occupy the site and are interested in staying where they are and developing further. Discussions are also underway with potential future tenants. Approximately 3,500 people already work on the site.

The urban development concept aims to retain certain historical structures of the site. Other buildings on the site are either in poor condition or unsuitable for new, forward-looking purposes, making it wise to demolish them for economic reasons. This will allow them to be replaced by new buildings with modern workspaces that will be attractive and available to companies from a range of industries.

  • A more open arrangement: what is currently a closed company site will be integrated into the Kleinbasel district. The Rosental neighbourhood, which is currently divided, will be brought together.
  • Connections: opening up the site will create new, attractive footpaths and cycle paths – for example, between the new Erlenmatt neighbourhood and the Sandgruben school and the Allgemeine Gewerbeschule Basel.
  • Housing: the new living spaces on the site will increase the housing stock available in the city and reduce commuter traffic.
  • Public spaces: new public open spaces, ground-floor units and rooftop spaces will create places for people to meet, which the area has hitherto lacked.

The basic concept for Rosental Mitte is defined in an urban development plan, which was presented to the public in January 2020. Local citizens will be involved as indicated below and their feedback will be taken into account in the planning process, where possible:

  • Proactive communication regarding the most significant planning steps, e.g. building development plans and zoning changes.
  • Involvement of local residents in the planning of open spaces, uses for ground-floor units and any interim usage that serves the community.

There will be structural densification that will take the type of building, the height and materials used in the neighbourhood into account. Small-, medium- and large-scale interventions are planned for the site. Investing in existing buildings will bring new, modern, commercial spaces to the market. In the medium to long term, among other things, high-rise buildings with a mix of intended uses yet to be defined will be constructed.

In order to open up Rosental Mitte entirely, structural changes to buildings and infrastructure need to be made. It may be possible to use buildings intended for demolition in the interim, though this will primarily be in the closed part of the site. Other options are being investigated. Where possible, companies that intend to develop in Rosental Mitte will be given tenancies in existing buildings.

Generating new jobs may lead to heavier traffic. Initial studies indicate that the existing road network will continue to function effectively, even in the case of structural densification. The existing district should be only minimally impacted by additional traffic.

In its final state, Rosental Mitte should generate very little above-ground traffic, and most of the parking will be underground. The final number of parking spaces will be kept to a minimum, taking into account the final usage and demand. With the aim of creating an attractive environment in mind, the option of a district car park on the Rosental Mitte site, as opposed to above-ground parking spaces, will be investigated.

Rosental Mitte will be continuously developed in a series of gradual steps, but a holistic perspective is required in order to proceed. The timescale depends on a variety of factors, including the demand for commercial spaces.

The first demolition projects are planned for autumn 2020 in the northern part of the district, to prepare the site for its future use. Discussions with companies interested in moving to and investing in the site will be initiated at the same time. Local residents will be informed of noisy demolition works in advance.

For buildings and usage that do not conform to zoning requirements, development plans will be drawn up based on the urban development plan and the results of future urban planning and architectural variance processes. The step-by-step development and opening up of the site means that experience from previous construction sites can inform future developments.

A basic report on the contamination status was completed in January 2017. Further investigations of the subsoil are currently underway. Long-term groundwater monitoring did not identify any issues in the current state and was stopped. The situation will change as a result of the construction work, however. Contaminated excavated materials, drainage issues and a renewed requirement for groundwater monitoring will need to be factored in during the construction phase. The canton will cover the cost of decontamination.

The project involves the complex transformation of a site that is still in operation. The urban development concept for the site was developed in the years up to 2018 and expanded in 2019, following the acquisition of the Syngenta site.

Buildings on Maulbeerstrasse and Rosentalstrasse that were once residential will again be used for housing. Another building in the centre of the site has the potential to be converted into cafés, restaurants or similar. Many of the existing buildings that contribute to the identity of the district will be retained in the medium to long term. For example, if the IWB heating and power plant on Maulbeerstrasse is decommissioned, the building could be converted into a cultural and event space.

A range of measures is planned to open up the existing industrial road space on the site and introduce new open spaces and parks. The new open spaces will provide places for people to meet and green areas. The restoration of the historical junctions will ensure that the route network is optimally integrated into the existing neighbourhood.