SOWING THE RIVERFRONT, DEVELOPING A WATER SENSITIVE CITY
CHILE - ITALY
CRISTIÁN BOZA WILSON
BOZA WILSON ARQUITECTOS
DANIEL VENEGAS ,
01_BASIN SCALE STRATEGY
From a methodological point of view, the project is structured around a double entry: on one hand, the territorial criteria based on the analysis of the basins and, on the other, the characterization of the river from the landscape evaluation.
Territory - basin The territorial analysis of the basin (s) was developed, with the help of a geographer, according to 5 key dimensions: geomorphology, hydrology, biodiversity, accessibility and current regulations.
This analysis allowed us to define the existing “natural capital”: the Nonguén National Reserve, considered the heart or main ecological head of the basin, the few fragments of native forest that still remain, the only partially protected sites (priority sites + private conservation initiative), the water systems represented by estuaries and urban wetlands. Furthermore, the analysis itself highlighted the spatial frag- mentation of ecosystem-based functions of the basin as the main problem.
Our proposal focuses on the reconstitution of interrelated ecosystems (water and vegetation) in order to guarantee a balanced ecosystem metabolism and provide the required environmental services to the cities settled in the territory.
The link, or the threading, between the different fragments will be possible through ecological corridors with native vegetation, which, wherever possible, will try to establish fingers, in order not only to guarantee a greater perimeter corresponding with a greater biodiversity, but at the same time a better way to intertwine the ecological side with ur- ban development.
The guiding principles of these ecological corridors have been determined by the following factors: the hydrograph- ic sub-basins, the streams, the hydric bodies and the index of the vigor of the vegetation (NDVI) granted by remote sensing. The result is a proposal articulated by 4 green infrastructural lines, achievable in stages, that once executed will be forming an interconnected system, which will lead to the regeneration of ecosystems and which will allow the city to achieve high quality of life indexes through the environ- mental services provided by the territory.
The landscape of the Andalién River was evaluated from the point of view of an observer on foot, through a photographic sample on the ground every 250 meters, in order to measure and characterize the viewshed along the entire path of the project (15 kilometers). This operation allowed to identify four main landscape units, summarized in the following sections: Subsector_River mouth Subsector_Urban residential park Subsector_Sports and educational equipments Subsector_New residential area
For each of these landscape units a specific proposal is suggested according to the characterization encountered, with- out betraying the basic principles shared by all: protecting the agricultural land, proposing new spaces for residential development and, along with that, new equipment of local scale, a connectivity network through secondary roads and paths with water bodies and the foothill, and, finally, the hydraulic containment through a habitable parapet in the areas occupied close to the inhabited areas.
At the urban scale, these basic principles are translated into three main actions:
- The Greenway, consisting of the formation of a ring of afforestation at the foothill as a measure of compensation for the excessive use of forestry and as a solution for connectivity and accessibility, both at ecological and anthropic level.
- The Blueway, consisting of the configuration of water axes that connect the wetlands with the river, and which are combined with a network of green infrastructure and a slow mobility system, such as pedestrian and bicycle lanes.
- The Riverfront, whose main action consists of thickening the river as much as possible, which is considered the main space for public use for leisure and enjoyment. For this purpose, the perimeter is consolidated through a structuring roadway in order to promote accessibility. At a later time, polygons of complementary development are added to this perimeter.
03_SITE SPECIFIC CHALLENGE
Having acknowledged the inefficiency and the little sustainability of the current urban models, for the residential scale, our proposal bets on the idea of an alternative urban growth system, more autonomous and sustainable, less dependent on the classic urban centralities, and whose system of organization mixes agroforestry production with territorial elements of environmental value, such as the foothill, the estuaries, the irrigation channels and the wild areas. This urban system aims at the development housing of medium density, articulated according to units in the form of pockets with estimated densities between 100 and 250 inhabitants per hectare. These pockets are conceived as neighborhoods, integrated with the nature and with a spatial figure that allows a precise identity and rapid appropriation by its inhabitants.
Both scales of design have been developed with the constant concern for the current regulation, in order to be as concrete as possible and find the actions and strategies through which execute the proposals in a short and medium term. This way at the territorial scale, part of the proposal is an Action Plan which is precise and adjusted to the different existing legal instruments. This Plan works as an objective, but also as a set of strategic guidelines, capable of leading other future initiatives and / or evaluating projects in the study area. At the urban level, the Action Plan is proposed as a guiding body for the modification of the Metropolitan (and communal) Regulatory Plan of Concepción in order to add new categories embed to the riverbank of the Andalién River and to the areas with an immediate urban development potential.