Polyvalent Adaptations

M.Arch Thesis

Year:                        2015 to 2016
Location:              Tongatapu, Tonga
Committee:          Ray Cole, Matthew Soules,
                                 Kees Lokman, Tony Osborne
Publication:         December 2016, Canadian Architect Magazine
Awards:                Canadian Architect Student Award of Excellence 2016

The full thesis book is available to read online or for download here.

Thesis Statement

“As the impacts of sea level rise begin to force human populations
to migrate to higher elevations, new infrastructures can be designed
and constructed to meet current needs, while also providing projective
agency capable of assisting in the aftermath of extreme weather events
and as polyvalent spines for new settlement patterns when
populations and individuals choose to migrate.”

Sea level has the potential to rise somewhere between one and a half and several metres by the end of the century.  Coinciding with this, a two to eleven percent increase in magnitude could lead to storm surges of nearly fifteen metres in height.  It is not unreasonable then to assume that in a worst case scenario, anyone living or dependant on land located less than twenty metres above current sea levels is at risk.

Tongatapu is a low lying island that has been almost completely  manipulated by humans.  The island is home to seventy percent of Tonga’s one hundred thousand inhabitants and has a density of 1,275 people per square kilometre.  With a reduction in land that could cut Tongatapu’s area in half, and an increasing population from foreign and internal sources, the population density could double this century.

The design portion of  “Polyvalent Adaptations” proposes a network of soft and hard infrastructures on the island of Tongatapu that will support and guide the inevitable process of migration.  The most prominent component of the design is the Vaota (or forest in Tongan).  Stretching the length of the island along the twenty metre elevation line through primarily agricultural landscapes the Vaota grows to become visually prominent over time, paralleling the increased pressures of sea level rise.  The Vaota becomes a signifier for new zoning, building codes, land use planning, engineering, architectural and cultural polyvalent infrastructures.  These infrastructures are interpreted differently in each of the three main phases of migration, while maintaining the ability to adapt to future uncertainties.

In the first interpretation, the infrastructure is a source for the resources required to meet the current needs of the coastal settlements and increases the island’s resource independence. This phase addresses issues such as water quality, water shortages, land tenure, health, agricultural diversification and energy.  As an investment to meet the present-day needs, this phase helps to justify the investment into long-term polyvalent infrastructure.

Following a devastating extreme weather event, the infrastructure is interpreted as an emergency support system.  With the increasing intensity and frequency of extreme weather events, this interpretation draws on Tonga’s long history of preparing for extreme weather and helps to justify investments into polyvalent infrastructure.

The final interpretation of the infrastructure is as a spine to allow for new settlement patterns.  When individuals, families and communities decide to or are forced to migrate, the infrastructure provides a draw which helps to guide new settlement patterns around it.  In a manner similar to the way previous settlements were drawn to their locations by natural infrastructures, resources and ecologies, new settlements can be drawn by constructed ones.

The research portion of this thesis explores the issues surrounding sea level rise and develops the idea of Polyvalent Adaptation as an approach to addressing these issues.  Tonga was chosen as a test location, however this approach can be applied throughout the world in varying contexts and at various scales.

The design, presented as a narrative, follows a young Tongan named Fokai through his life in Tonga over the next several decades and is accompanied by drawings and diagrams.  This manner of presentation brings this large infrastructural project back to the human scale and highlights the polyvalence and temporality of the project.