Introduction By Fadi Masoud

Sequence of accumulation and transformation of the Leslie Street Spit over the past 40 years - showing access system and planning.

INTRODUCTION

By Fadi Masoud

“It [archaeosphere] is more than a record of human action. It an ecological entity of global scale, exerting and radiating its own influences and impacts almost independently of the latest generation of people who fleetingly inhabit its changing surface and leave the most recent marks upon it.”

–Matt Edgeworth

One of North America’s largest colonies of double-crested cormorants, along with hundreds of plants, animals, and migrating bird species, populate a 5km stretch of artificial terrain on the northern shores of Lake Ontario. At the edge of Canada’s largest city, this artificial breakwater and active construction dump site has fortuitously become one of the Great Lake’s most significant ecologically sensitive areas. Originally conceived as an extension of the Toronto Harbour, the Leslie Street Spit is the result of five decades of lake-filling by the Toronto Port Authority. The Spit is representative of what has come known as the “archaeosphere”, a new stratum at the intersection of archeology, geology, and ecology. The archaeosphere, described by geologist Matthew Edgeworth (2018), is the set of anthropogenically-modified deposits that now cover large parts of the terrestrial surfaces of the Earth. The archaeosphere, not only includes artificial terrains composed of the dirt and rubble moved and accreted by human activity, but also layers of the techno-sphere (cables, pipes, machinery…etc.), as well as biotic elements (bacteria, fungi, critters, roots). The archaeosphere occupies the surface environment where the geosphere, biosphere, atmosphere, human beings, and the energy from the sun interact; identified “as the most heterogeneous portion of the Earth”. It is extremely vibrant, active, and “can be regarded as having an independent existence in its own right”.2 Embedded in the landscape of the Leslie Street Spit is the history of urban socio-economic transformation of the city. As Foster (2007) explains, “It [the Spit] juxtaposes a degraded and discarded city with fertile and vigorous ecology, a place where nature has colonized the post-industrial urban spoils”.3 A multitude of living organisms flourish in the rubble of demolished Victorian-era slums, 1960s housing projects, the excavation of Mies van der Rohe’s TD Centre complex foundations, the hundreds of kilometers of subway and underground shopping tunnels that crisscross the city, and the city’s most recent condo tower boom. Not too far from the Spit, excavation from “The Well” mega project on Front Street and Spadina Avenue is used to fill in new lands for the Michael Van Valkenburgh Associates designed promontory park and flood protection landforms of the new Lower Don

Lands. This new, artificial, ground itself has become an environmental entity, shaping other things as much as it is shaped by them. The successional, mostly non-native vegetation that form much of the basis of its rich biodiversity is thriving on nonnative soils. As ecologist and botanist Peter del Tredici asserts, it is in this archaeosphere where a native ecosystem is not possible that we can “support a functional cosmopolitan ecology”.4 In the context of a book on the global extents of urban land reclamation, it is pertinent to consider the interrelation of ecology, archeology, and geology in the shaping of terrains – especially along the littoral edge. Over time, urbanization and its associated processes secreted and accumulated layers of material on top of which further growth and development has taken place. The continued shaping and reshaping of a new global littoral edge during a climate crisis implore us to intentionally design and shape this archaeosphere. Today about half the world’s population lives within 100 km of the coast or an estuary, where eight out of the ten largest metropolitan regions are currently situated. Naturally, coastlines are shaped through time by the processes of erosion and accretion, where they play a pivotal role for a robust economy and natural defense. Today we are the most significant agent of global erosion and accretion. This atlas of urban districts on reclaimed lands and contributing essays point to these massive land shifts where there has been little consideration for the surrounding environment. Inaction in the face of coastal climate change impacts would be detrimental to huge swaths of urban populations. Yet to accommodate the rates of urbanization, population growth, and economic development, many coastal cities continue to expand into the littoral edge despite threats of coastal subsidence, sea level rise, storm surge, and ecological deterioration. Coastal land reclamation undertaken by cities is not a modern phenomenon, but the pace, scale, and ubiquity is. As such, this book stems out of the need for a more robust environmental strategy that combines technological advancement with novel, resilient, adaptive, and dynamic coastal urban developments. A lag in the industry and governance structure of the shaping of the littoral archaeosphere means design innovation has agency in this transformation. In a recent article of the quarterly magazine of the European Dredging Association, industry authors reflected on why “nature-based solutions” – the integration of blue-green landscape systems with grey infrastructure to form hybrid system – do not represent a valid option for coastal and flood defenses on reclaimed lands. They noted how the evolution of nature-based solutions “implies an element of uncertainty”. As such, “existing traditional public procurement methods, governance,” as well as the business cost-benefit assessment models are “not suitable for nature-based solutions absent different types of guarantees”.5 Guarantees of of static permeance on the most dynamic littoral gradients and thresholds of our planet is futile. The goal of this book is to imagine a future that engages the archaeosphere along degrees of permanence and dynamism as the physical site of interrelating forces of economy, ecology and culture. The book recognizes the need for littoral transformations that embody tangible characteristics of adaptive and resilient landscapes and urban forms. This ranges from novel dredging techniques that generate gradients of inundation and socio-economic activities, alternative natural materials to address the scarcity of sand, selective urban