Most of our Latin American cities have grown from the center to the periphery, Lima is one of them, a large oil slick that dilutes towards the Andean buttresses. As a consequence of the lack of planning in all its scales and sectors, we have built a very diffuse urban scene, which has only been tried to guide in the form of a huge palimpsest with measures of a populist nature, incoherent and lacking technical criteria.
The population reservoir attacked on Lima between the 60s and 80s, due to the migration from the countryside to the city produced, among other causes, by centralism and the failure of the agrarian reform was the golden opportunity for land speculators to solve the “criollaso” the demand for housing, also supported by regulatory norms for the empowerment of land for urban purposes.
Indeed, Decree Law 17716 or the Agrarian Reform Law, was the great support for the great traffickers and land speculators for the beginning of the overflowing and predatory growth of the agricultural land that surrounded our capital city. Then it was just a consumer whirlpool of our support system to maintain the prevailing type of urban organization. In this way, the “diffuse city” model was consolidated.
The diffuse city model consumes a large amount of energy to carry out its urban functions, such as mobility, building and services. The zoning is developed through large spots or areas assigning a single function-functionalist planning-looking for the "compatibility" between the land uses that are increasingly dispersed. Therefore, the connection between them can only be made by motorized vehicles through a dense and complicated network of segregated roads and highways, from which private transport is favored and public transport is partially excluded, limiting it in its coverage.
Urban growth is fed by the mobility network to spread almost everywhere, without respecting agricultural areas, urban interstices, hills, dunes, or swamps, all will be devoured by urbanization, which in turn will increase the pressure on its support system by exploiting its resources, such as soil and water, and will carry out activities with a high polluting impact, such as the great distances that informal and formal urban transport will cover to cover this great urban expansion.
According to the Margalef Principle, the most complex systems capture information and energy from the simplest systems. Something similar occurs in urban systems, the areas with the greatest diversity and heterogeneity in the city, extract energy, resources and information from the most homogeneous and dispersed areas. Not long ago, the large peripheral areas or poverty belts of Lima, moved ingest from pole to pole, seeking information and labor towards the central and consolidated areas, making urban organization more complex in the center and simpler in the peripheries.
Simple and homogeneous urban organization areas generally contain low density rates and in the case of Metropolitan Lima they experience a high degree of urban unsustainability and inefficiency. The space tends to a functional specialization (mono functional) and the contact, regulation, exchange and communication between different people, activities and institutions is impoverished in the territorial space.
On the contrary, the compact city model consumes less energy, because urban functions are more concentrated, it presents multifunctional areas, its density is higher and therefore it has a higher level of urban compactness than the diffuse city.
Compactness expresses the way in which the urban territory is physically organized and has to do with that old dichotomy of form and function but on the urban scale. The compact city model has to do with four vital elements that are: spatial planning, urban planning, mobility and public space, multi-scale and interrelated elements.
The proximity of uses and functions of the compact city favors public transport, providing it with a critical mass that ensures its profitability, durability and generates an attractive service offer, with comfort and above all constant. Public transport can be rationalized so that it can cover a larger portion of the city, at a lower entropic cost and therefore generate fewer polluting impacts. In turn, mobility is less and gives us the opportunity to choose a wider range of modes of transport, such as cycling or on foot. An increase in urban complexity and diversity represents a greater proximity of land uses, but also an increase in vertical mobility.
The compact city revalues the inherent nature of public space, which is the place par excellence where we exercise citizenship. The street, the square and the facilities make up an integrated and interconnected system that constantly nourishes and nourishes civility. The compact city is more democratic, because it ensures access and enjoyment for any citizen. It is inclusive and improves social cohesion. Compact cities, given their complexity, develop greater urban efficiency and are therefore more competitive compared to other urban areas that fight for the same resources.
It is necessary to rethink and reflect on this dialectic between the compact and diffuse city, because we see every day huge residential buildings grow on the same and over-exploited support system, which already exceeded, a long time ago, the operating thresholds and coverage and on the other hand, we also witness the accelerated and anxious urbanization of the northern, southern and eastern peripheries of metropolitan Lima following the fuzzy logic. The urban renewal of the consolidated areas of Metropolitan Lima is an important undertaking, but it would be more profitable if we imbue it with the ingredient of urban sustainability.
