After the team of Jan and Tim Edler from Berlin-based realities:united won two LafargeHolcim Awards, the local response to their seemingly wild proposal changed dramatically. Their ambitious idea to create an enormous public bath in Berlin’s Spree River in close proximity to the UNESCO World Heritage Museum Island wasn’t immediately basking in public enthusiasm. Architect Tim Edler explains: “Before winning the competition, we were considered crazy. After we won the Holcim Awards Gold for Europe and then also won the Global Holcim Awards Bronze, people had to ask themselves why we were awarded 150,000 USD for a project that no one knew about in Berlin. It was really first the recognition from outside the city that furthered our efforts locally.”

The comments by international experts and media coverage spurred greater interest in the project, and by 2014 the concept of a 830m-long public bath in the center of Berlin had garnered widespread international attention. Subequently, this momentum aided in securing an additional USD 3.2 million awarded by the National Project for Urban Development (Nationale Projekte des Städtebaus) to develop the proposal further.

Wading through new challenges

However, the complexity of land ownership and the historic significance of the site have also created new challenges. Since many federal, state and local actors are involved and the project site is not under the sole jurisdiction of a single entity, a second round of detailed feasibility studies is currently under way to investigate how to break the project up into smaller parts, while maintaining smooth project delivery. In part, the detailed study involves looking carefully at how pedestrian movement and accessibility would be impacted during sequential phases, as well as how the different trades that make up the construction teams could be organized to produce the most environmentally sensitive and cost effective results.

Meeting the overarching goals of heritage protection while being minimally invasive to the site is another ongoing discussion between the project design team and heritage protection authorities. In recent meetings with local representatives from the “highest” national monument protection authority (Oberste Denkmalschutzbehörde), the state authority for monument protection (Landesdenkmalamt), as well as the “lower” national monument protection authority (Untere Denkmalschutzbehörde), concerns over interventions were voiced. Specifically, the discussion with these groups has focused on physical changes such as the introduction of concrete stair elements and the visual impact of the environmentally friendly water filtration system, which includes plants and bivalves, on the aesthetic of the water surface .

A bit more puzzling to the design team has been the reaction of lobby groups such as the Society of Ancient Berlin (Gesellschaft Historisches Berlin), who have identified the presence of bathers as problematic. Yet, the architects are still optimistic that the discussions between the design team and heritage advocates are raising important questions about how to balance the local community’s desire for more public space and improved water quality with the protection of historically significant sites.

Tim Edler (pictured, left) elaborates: “We really believe that the narratives of the sustainable city and heritage protection can be combined in the project and can profit from each other.” In order to address these issues, the design team has developed a series of demonstration projects that will be launched in early 2017.

Planned demonstration projects

Many bathing areas existed in the Spree until high levels of water pollution forced their closure in the early 20th century. The European School for Management & Technology (ESMT Berlin) now occupies one of these sites in the Mühlengraben area of the Spree Canal. The ESMT are active supporters of the Flussbad Berlin Association and will make an 865m2 area including a former bathing site available at no cost for a demonstration project from early 2017 to late 2018.

A wooden platform will trace the foundations of the former public bath known as the “Doppel-Badeanstalt” (double bathing area, pictured left), which was in use from 1895 until 1925 and located in a branch of the main canal that existed until around 1954. The planned wooden platform will include an exhibition and discussion area to showcase topics relating to the project such as how the water treatment strategy will integrate the city’s existing overflow retention infrastructure. In parallel, constructed wetlands will purify incoming river water in an environmentally friendly way that uses the naturally occurring filtration properties of plants and bacteria to improve water quality. The site will also act as a summer event location and a presentation space for other projects dealing with urban public space. The platform, which is still in the planning phase, will be constructed on a 1:1 scale based on historical sketches and will provide the public with a window into the history of Berlin’s public bathing culture.

In addition to the information platform, a scaled down version of the natural filtration system planned for the Flussbad will be constructed and housed within a historic barge called the “Hans-Wilhelm,” which belongs to the Port of Berlin. The testing facility will be in operation for two years with the aim of monitoring and refining the water filtration system that must function under a wide fluctuation of water pollution. Much of the filtration process will be visible to the public, since the ship is moored below the quay wall and the filter basins will be visible.

Understanding heritage protection as a generator of new public space and environmental regeneration

These lighthouse projects are not only important measures to communicate the potential impact of the Flussbad project to inspire local residents, but they simultaneously provide the design team with opportunities to verify and elevate technical dimensions of the project. These efforts also highlight the methodical working process of the trailblazing project team and how daring design thinking does not happen in a vacuum.

While political support continues to be strong across parties, Tim Edler hopes, “the newly elected government in Berlin will remain very confident about the project.” Certainly, political support will be critical for the realization of the Flussbad. But ultimately, it will be the public’s strong embrace of the symbolic and functional possibilities of the project – the creation of a unique and inclusive public space in the center of the Berlin that is both sensitive to history and the environment – that will bring this ambitious proposal to reality.