All Studio projects must be justified on the basis of a vulnerable population to which has been called the social background. Seeks d thus incorporate social components since the beginning of the project and identify nodes and connections beforehand, so that there is not only to swell the size of the libraries. 1.3 Public goods for the purposes of this work and in order to better understand the responsibility of the State in matters of prevention and attention of disasters, I now turn to one of the most appropriate and basic concepts. There are some goods that, or are not supplied by the market or if they are, the amount supplied is insufficient. An example is a large scale national defense and another on a small scale, the AIDS to navigation (e.g.

buoys bright). These are called pure public goods, which have two properties. First, it costs nothing else more to enjoy its advantages. Formally, the fact that an additional individual to enjoy good, has a marginal or null cost. It costs no more defend a country of one million and one person defend one of a million.

The costs of a luminous buoy do not depend on the number of ships passing through nearby. Secondly, in general it is difficult or impossible that you enjoy not the public good. If we place a luminous buoy at a rocky area that our ships can sail without danger, it is difficult or impossible to prevent others to navigate through this area. If State policies in the field of urban planning and disaster prevention can minimize the risks against seismic movements, we all benefit; It is not possible to exclude any person from these benefits (string: 1999). The security of citizens and their property constitutes a public good. The State is responsible for providing security citizen through the development and requirement of the compliance by its partners, policies to protect their lives and their property.

Colombian Earthquakes

Towards the South and up to 350 kilometres, causing further damage earthquakes have occurred. Bogota has been partially destroyed or damaged not only by distant origin earthquakes but also by movements originated in the vicinity (ANDRE: 1884). In relation to the inherent to disaster prevention and environmental management activities, it is inevitable to conclude that in Bogota have not existed coherent inter-agency organizations to carry out these activities. On the other hand, presents a dispersion of entities that from different sectors and at different levels have been exercising one or several functions of management or control of factors of risk and environmental deterioration. The geologico-geofisico model of the urban perimeter of Bogota and its surroundings ((is conformed by two sub-basins: 1) the Western, located towards the Northwest, 2) the East, located inside the urban perimeter and branched in its northern part by the hills of Suba, giving rise to two secondary sub-basins, one the the western part of the hills of Suba and another between these and the eastern hills (BERMUDEZ: 1942). Scientifically in Bogota three major seismogenic sources are clearly defined: 1-.

It corresponds to the subduction zone of the Pacific coast, which is significant only for some parts of the subsoil of the city response characteristics. 2 Corresponds to the front source of the Cordillera Oriental, which is dominant in the case of the city. 3 Corresponds to local sources even though the seismic threat for Bogota does not correspond to extreme values in the country, the risk is because of the high degree of vulnerability of its buildings, which until a few years ago were built without taking into account the criteria of sismo-resistencia. The designed buildings and built before 1984 are highly vulnerable; This has been proved during the occurrence of low intensity earthquakes registered in other regions of the country (BALTA: 1926). The main reason is that prior to the implementation of the Colombian code of Sismo-resistencia, there were no clear requirements on earthquake-resistant materials, design, and techniques. The incorporation of the concepts of development and socio-economic and physical planning, as well as the active participation of the communities, is still weak in most district agencies responsible for disaster prevention.