On 11 March 2011 the strongest earthquake in the history of Japan hit Tohoku, generating a tsunami that killed 24.000 people and completely destroyed almost 100.000 households. In response to the disaster, the Harvard for Japan group was soon created as a multi-disciplinary team of researchers and designers that offered support to the affected regions during the reconstruction process.

Through Harvard for Japan, we joined a one-month workshop with the local government and city planning consultants on the new masterplan of Shizugawa, a city of 18.000 inhabitants that had been almost annihilated by the tsunami. When we started our project, the local authorities had already taken most of the strategic decisions and we were asked to operate within a set framework of functional zones, dividing our work in four main themes: residential, commercial, industrial and park. reMIX worked on the new residential neighbourhoods, which were planned to move from the costal plane to the adjacent hills. The initial masterplan defined three major zones for such relocation, with a scheme that implied a deep modification of the original topography (i.e. flattening all the hilltops in order to build on flat grounds) and would require long and very expensive earthworks.

From the analysis of the current conditions, we were able to identify some areas, within the planned residential zones, where the slopes are low enough to allow construction with minor interventions in the topography. This led to the creation of a parametric model of terraces and buildings that optimizes the earthworks and creates a flexible infrastructure for the urbanization of the hills. Different prototypes of soil-retention and building typologies are then associated to various slope conditions. Parameters such as minimum and maximum plot sizes, setback, building dimensions, solar orientation etc. informed such analysis.

By combining different slopes with specific typologies, such system would not only minimize the costs of urbanization, but it would also create a multifunctional and differentiated neighbourhood, avoiding the homogeneity that often arises from large scale developments built at once in uniform conditions. Finally, a terracing system instead of the complete flattening of the hilltop would also allow a faster and more flexible implementation of the infrastructure as the neighbourhood could grow through different independent phases.