Conclusion
Earthquakes are tragedies. Yet they can serve as the laboratories for understanding the physical and the social factors covering them. Because earthquakes have both immediate and long term impacts, post disaster studies should be conducted so that lessons can be learned at all phases.
The subject of this thesis was decided after Marmara Earthquake. Many people were killed not by nature but by the mistakes of the people themselves. This earthquake and general mistakes made by the authorities were outlined in Chapter 3. There was no system, no control, no coordination, no organization, no technology, but there were wrong policies, wrong site selections for every facility, confused and imprudent administrators. Building an interrelation of urban information system and earthquake management brings new technologies, basicly geographic information technologies to this field. An urban inventory was created in Chapter 4 and a large data bank of a city was analyzed by computer technology according to a particular purpose- protection and recovery for saving lives against earthquakes.
The proposed system brings automation, sharing and exchange of information, team work and dynamism. Making comparison gets easier by seeing the analyses and the syntheses. Real time updating can be made immediately which can take the decision-makers to more accurate and righter thoughts and policies. The databases were built which contain physical, social and demographic data, so the residents who have building rights can be designated. The system can make some analyses, that not visible to naked eyes, like earthquake scenario, risk mapping, overlaying, three dimensional mapping, microzonation and vunerability studies as the contribution of the system to the earthquake management.
After proving the value of the interrelation of urban information system and earthquake management, it is seen that individuals and governments must begin to think of disasters as natural aspects of life that must be incorporated in day-to-day decision making. But first, a collective study should be done by different groups like national and local government, design professions, private companies, international or non-governmental organizations, educators, public interest groups and the volunteers.
Governments establish the baseline level of risk by legislating building codes and setting safety standards. They identify the priority areas for action and the role of private and public sectors in bringing it about and coordinate the budgeting for achieving the protection levels. An earthquake management system was proposed in Chapter 3. Because as seen in Disaster Acts, the organization is all related to central governments, it is static and all duties of officials were drawn for the phase of earthquake recovery. There are no preparedness, mitigation and response studies in legal framework.
So, a new office was built in local emergency center dealing with the studies about earthquake protection. Technical experts and teams work under this office for the protection of public and increasing awareness of the public about this subject. Technical experts use urban inventory designed in Chapter 4, queries and analyses in Chapter 5 to make in depth studies with the help of geographic information technologies. These experts can share the built database system with other authorities with the common fields. The Bureau of Recovery and Mitigation also use these kinds of technologies for the earthquake recovery. The duties for all officials working in emergency center were drawn one by one for better and safer cities. Other national and international organizations for help were explained in Chapter 3. The role of private companies and individuals is very important for earthquake protection, too. The other adjacent local governments should be involved in this preparedness and recovery studies.
It was shown in the results of the queries explained in Chapter 5 that the case study area, Pendik is very dangerous for a future earthquake. Because all the data used in the case study is all the real information dated 2001. Also a field study was done counting over 800 buildings one by one in a neighborhood. After GIS analyses, it is seen that many buildings, schools, health centers, industries and their infrastructure are on the alluvial lands. It is seen that Bati Neighborhood is the center and based on alluvial land. There are streams and aquifers under many governmental buildings including Pendik Municipality. The hospitals and health centers are not enough and their capacity is low. Pendik State Hospital has 50 beds. The maximum number of floors is 5 in plans but there are 6 or more storey buildings near to the coastline.
The road network is complicated, there are many cul-de-sacs especially in squatter areas. There is natural gas network in many neighborhoods but the main pipes and tank are located on unstable land which has liquefaction risk. In central part, many commercial facilities are situated on the ground floor of the residential buildings.
There is no precaution, strengthening the buildings or relocation projects by the central or local governments. However, these studies, suitability and capability analyses should be done immediately by the help of geographic information technologies. All the probabilities should be considered with looking at a wider perspective.
The system built for Pendik was site- specific. Because it was built with the local values, inputs of the district. But, maybe, similar methods can be used in similar unsafe districts near sea in I stanbul showing the similar characteristics of ground and man-made structures.
What-if scenarios for emergency routing were very useful for Pendik. There were two junctions on E-5 Motorway and three bridges overpassing E-5. If the junctions are closed and the bridges collapse, there will not be any connection between two sides of the district by motorway. Only airway can be an alternative for this kind of scenario.