By Rory Stott

There is a general agreement in our era that, when designing significant changes to a city, the participation of as many of the people affected as possible is crucial. Participatory processes are not only preferable for their connection to ideals such as democracy and community empowerment; they also produce projects that meet their goals more successfully and are more popular among residents and users. Unfortunately, the modern reality of cities is that economic, demographic, and political shifts can happen at huge scales. When urban projects are sparked by flows of people in tens of thousands, or money in billions, changes happen at a scale that can stretch participatory processes to their limits and leave local people feeling ignored.

These issues were at the forefront of the minds of MVRDV’s designers as they developed our proposal for the Werkstadt Grasbrook competition for Hamburg. The Werkstadt Grasbrook is a plan for 6,000 apartments and 16,000 jobs to be created on the Kleiner Grasbrook Island, becoming the first link in Hamburg’s long-planned leap across the Elbe and the catalyst to link the city centre with the south of Hamburg. The masterplan is a spiritual successor to Hamburg’s HafenCity plan on the north of the river. As Europe’s largest urban regeneration project, the completed HafenCity will be home to around 12,000 people and 40,000 jobs; it has been under construction since 2001, with completion finally expected between 2025 and 2030.

Faced with a project of a similar scale, the project team began to consider ways that such a large masterplan could feasibly incorporate the principles of participatory, collaborative urbanism in a way that would cater to the vast number of people affected. They also considered how a project with a delivery period measured in decades might remain relevant so long after its initial design. Could they engineer a process in which stakeholders could contribute to a design in a way that negotiates between neighbours’ desires? More importantly, could they do so in a way that can leave room for the unpredictable needs of future participants and future societies?

Their answer to these questions was a "Serious Simulation Game" known as the Grasbrook Maker. This software presented an interactive platform to playfully explore different possibilities for the future development of Grasbrook: a new model of urban planning that could be used, played, and developed by the people of the neighbourhood, who have knowledge of the place in question.

As in every game, the Grasbrook Maker has a set of rules. The designers set the Framework, local participants can define and place the Public Projects, and developers and entrepreneurs can develop the Urban Blocks. The Framework and Public Projects, which the project team call “activators”, are developed specifically for Grasbrook in response to the site. In the case of Grasbrook specifically, the Framework began with a Modular Grid based on the existing heritage; a Main Spine from which smaller streets on both sides could grow organically, like a tree, towards the waterfront; and a Mobility Centre located on the crossing of the Metro stop and the bridge over the Ringroad and Railtrack to the Veddel neighbourhood.

Players of this game are asked to collaboratively define their ideal urban layout for the area. After this initial collaborative design process, the Grasbrook Maker completes the masterplan: using an algorithm, it automatically places urban elements such as residential blocks or office buildings according to the layout it is given, with access roads to each building generated in the most efficient way. The software takes advantage of simulation to immediately predict the impact of participants’ decisions, and gives players a scorecard with relevant data for their proposal. In this way, every time the game is played, these evaluation sheets can inform or improve the subsequent rounds of design, creating a positive feedback loop that guides players towards the results they want.

The goals of the Grasbrook Maker may at first seem somewhat idealistic. It purports to be an intuitive – even fun – way for people to collectively design large swaths of their own city, given only a computer-aided-design tool pre-programmed with a relatively simple set of rules. But the recent history of technology, and of the internet in particular, has shown that such conditions are fertile breeding grounds for communal creativity, and that spectacular complexity can arise out of surprisingly simple rulesets.

An unexpected example of such a communal creative project was a social experiment initiated by the online forum website Reddit. As part of a series of ‘April Fools’ experiments, in April 2017 they launched r/Place, a forum that included a blank white canvas of 1000 x 1000 pixels. Users were allowed to change the colour of a single pixel, which would initiate a timer that counted down to the next time they were allowed to place a pixel (typically 5 minutes, though it varied over the course of the experiment). All users worked on the same canvas, and users could overwrite pixels already placed by others. These were the only rules, accompanied by a short welcome text: “There is an empty canvas. You may place a tile upon it, but you must wait to place another. Individually you can create something. Together you can create something more.”

It didn’t take long for users to realise that they could make use of Reddit’s existing infrastructure of forums and group chats to organise more ambitious creative projects as part of a community. Each community developed systems of organisation and communication in order to work together towards a single goal, while communities that found themselves next to each other on the canvas had to negotiate with, and at times even battle against, other communities for space. The first-hand accounts of those involved tell tales of enemies and allies, expansions and invasions, pacts and compromises, collective philosophies constructed with memes, leaders, ambassadors, and spies.

Over the course of 72 hours, millions of people worked together to create an artwork comprised of almost 1,500 individual pieces that was constantly in flux, constantly being refined but, like an asymptotic curve, never reaching a state of final completion.

This process has most often been compared to politics, but in its creative aspect it also mirrors the development of cities. Just like r/Place, cities are created by large numbers of people working in a network of communities, debating over what should be constructed, where different elements should go, and how they should look. The construction of cities is a high-stakes exercise, having a significant influence on people’s quality of life, and as a result, over time cities have developed extremely complex sets of ‘rules’ in the form of laws, economic structures, and institutions. But Reddit’s April Fools experiment shows that complexity can also emerge from surprisingly simple rules, given the low-stakes environment of a software platform. The promise of the Grasbrook maker is that the two processes can be combined, offering a system in which truly participatory urban design can be recreated at a scale and speed that would be unfathomable through existing methods.