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Accueil du site → Master → Etats Unis → 2011 → Water, Agriculture + settlement design in the arid lower Colorado River Basin : 3 new models

Massachusetts Institute of Technology (2011)

Water, Agriculture + settlement design in the arid lower Colorado River Basin : 3 new models

Wirth, Timo Matti

Titre : Water, Agriculture + settlement design in the arid lower Colorado River Basin : 3 new models

Auteur : Wirth, Timo Matti

Université de soutenance : Massachusetts Institute of Technology

Grade : Master of Science 2011

This thesis investigates possible conversions of an increasingly unviable type of irrigated agricultural landscape, seen under the influences of three simultaneous processes : urban growth, change of cropping practice and return to the desert. Three new prototypical models are designed and tested : an urban-rural oasis, an adapted rural settlement and an inhabited desert park. An analysis of historical hydrological alteration and agrarian/urban settlement processes in the Colorado River Lower Basin focuses on a region in a pivotal situation : Central Arizona and its agricultural irrigation districts. Here, the three models are tested on a hypothetical site of one square mile and simultaneously investigated in an abstract matrix of regionally applicable principles. In an increasing order, the urbanrural oasis, the adapted rural settlement, and the inhabited desert park reduce water needs by rainwater harvesting/-storage and greywater re-use. They are resilient towards droughts by allowing farmers to temporarily fallow agricultural elements, or, in the case of the desert park, by hosting partially seasonal uses and importing drinking water as necessary. The urban-rural oasis relies on a localized form of agriculture that allows selling all produce directly on site, mainly to its inhabitants, with a large recreational emphasis. The adapted rural settlement targets the emerging new food markets in the urban region with high-value crops, and diversifies production to include native agroforestry for energy production and woodcraft. The desert park contains a low input-output dryland agriculture and sporadic recreational desert harvesters. All three models rely on phased forms of settlement growth, increased income opportunities on site by the (re-)combination of land uses and the creation of microclimates by a strategic arrangement of vegetated land cover in proximity to settlement. Residential options span from medium- to low-density detached courtyard types ; different sizes of garden homes, haciendas and farm communities to desert villas, and even RV campgrounds ; with the urban-rural oasis having the largest range of choices among the options. Each model may attract broad concentrations and ranges of regional lifestyle groups between urban/suburban, agrarian and nature-oriented communities, of a permanent or an ephemeral nature. A single overarching condition is the realistic acknowledgment of both the obvious challenges and plentiful qualities of the desert. Various cultures could unfold together with the idea of saving water. There seems to be an enormous potential in converting the agricultural landscape into a more resilient and diversified one, along pathways proposed by the three models. Moreover, attempts to free up volumes of water on large sites would be one of the fundamental necessary steps to more permanently embrace both human and natural life in an arid and unique environment like the Lower Colorado River Basin

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Page publiée le 31 décembre 2011, mise à jour le 25 septembre 2019