Sel risk yönetimi kavramının değişen çerçevesi ve mekansal planlama ile ilişkisinin incelenmesi: Edirne örneği
Assessment of the changing framework of the flood risk management approach and its relation with spatial planning: Edirne case study
Yazar: EDA MUTLUAY
Danışman: PROF. DR. AZİME TEZER
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Şehir ve Bölge Planlama Ana Bilim Dalı / Şehir Planlama Bilim Dalı
Derece: Yüksek Lisans, 2019
Konu: Şehircilik ve Bölge Planlama = Urban and Regional Planning

Özet:
Sel ve deprem dünya üzerinde en fazla zarara neden olan doğal afetlerdir. Birleşmiş Milletler Afet Risklerini Azaltma Ofisi (UNISDR) tarafından, son yirmi yılda dünya çapında selden etkilenen toplam insan sayısının yaklaşık olarak 2.4 milyar olduğu tahmin edilmektedir. Yine Centre of Research on the Epidemiology of Disasters (CRED) tarafından yayınlanan ve son yirmi yıl içerisinde gerçekleşen afet rakamlarının açıklandığı rapora göre 1998-2017 yılları arasında gerçekleşen afetler içerisinde sel, %45 oranla ölümle sonuçlanmasa bile dünyada diğer türler içerisinde en fazla insanı etkileyen afet türü olmuştur. Tüm dünyada iklim koşullarını etkileyen ve küresel bir sorun olan iklim değişikliğinin olumsuz etkileri sel riskinin günümüzde giderek artan bir sorun haline gelmesine neden olmaktadır.. Dünya Bankası'na göre, iklim değişikliğinin olumsuz etkilerine bağlı olarak dünya çapında küresel sel olaylarının sayısı son altmış yıl içinde giderek artmıştır. UNISDR tarafından yayınlanan verilere göre, dünya çapında sadece 2018 yılında meydana gelen sellerin 91 milyondan fazla insanı etkileyerek 37 milyar $ zarara neden olduğu görülmektedir. Bu duruma, devam eden hızlı kentleşme süreci ve iklim değişikliğinin etkilerinin olumsuz etkilerinin dünya çağındaki meydana gelen sellerde öncü faktörler olduğu söylenebilir. Daha da kötüsü, istatistiklere göre sel olaylarının toplumlar ve ekonomiler üzerindeki etkisinin dünya genelinde nehirler, deniz kıyıları ve okyanuslar boyunca kentleşme hızına bağlı nüfus yoğunlukları ve ekonomik faaliyetlerin artışı nedeniyle gelecekte daha da artabileceği tahmin edilmektedir. Küresel ısınmaya bağlı olarak büyük nehirlerin yıllık maksimum deşarjlarının 2050 yılına kadar %3 ila %9 arasında artması beklenmekte ve bu durum da daha şiddetli kıyı sellerinin ortaya çıkmasına yol açabilecektir.
Sel riskinin hem toplumlar hem de ekonomik yapı üzerindeki olumsuz etkileri ve küresel ısınmaya bağlı olarak gelecekte daha büyük bir tehdit oluşturması, sel risk yönetimi kavramına özel olarak ilgi gösterilmesi gerekliliğini ortaya koymakta ve tezin bu konu bağlamında yazılmasının gerekçesini oluşturmaktadır. 
Sel tehlikesinin doğal bir risk unsuru olarak kentleri tehdit ettiği kabul edilip sel riski çeşitli önlemlerle kontrol edilmeye çalışılsa da; alınan önlemler ve sel riskine bakış açışı zaman içerisinde yıllar boyunca değişmiş ve çeşitli kırılmalara uğramıştır. Sel risk azaltım yöntemlerinde yaşanan bu paradigma kayması zamanla dünyadaki farklı ülkelerin çözüm yaklaşımlarında yer almaya başlamış ve dünyadaki sel risk yönetimi yaklaşımı bahsedilen salt yapısal mühendislik çözümlerine dayalı parçacıl önlemlerden; yapısal olmayan ve ekolojik temelli, çoklu/bütüncül önlemleri kapsayan ve bu önlemleri mekansal planlama araçlarına dayalı olarak gerçekleştiren bir noktaya doğru kaymıştır. 
Bu noktada tezin amacı ilk olarak, dünyadaki değişen çerçevede sel risk azaltımı politikalarının, seçilen dünya örnekleri özelinde zaman içerisinde yaşadığı paradigma değişiminin arkasındaki itici faktörleri açıklayarak sele meruz kalan bu ülkelerin değişen sel risk yönetimi yaklaşımlarını belirlenen kriterler aracılığıyla incelemek; ayrıca sel risk yönetimi kavramının değişen çerçevesi içerisinde mekansal planlama araçlarının rolünü tanımlayabilmektir. 
Tez kapsamında örnek alan çalışması olarak incelenen Edirne kenti, bulunduğu coğrafi konum nedeniyle Meriç, Tunca ve Arda nehirlerinin kesişim noktasında bulunmaktadır. Meriç, Arda ve Tunca nehirlerinin havza sınırlarının Bulgaristan ve Yunanistan'ı da kapsaması ve nehir menbalarının bu ülkelerin kontrolünde olması sebebiyle Edirne kenti tarih boyunca çeşitli sel afetlerinden etkilenmiştir. Tezin kapsamı içerinde yer alan ve dünya örneklerinin incelenmesiyle doğruluğu test edilecek bu paradigma değişimini Edirne'nin sel risk azaltım yöntemleri çerçevesinde mekansal planlama araçları olan ilgili mevzuat ve mevzut mekansal planlar kapsamında irdelemek ve dünya örnekleri ile örnek çalışma alanı Edirne'nin sel risk yönetimi yaklaşımlarını karşılaştırmak tezin ikinci amacını oluşturmaktadır.

Abstract:
Floods and earthquakes are natural disasters that cause the most damage on Earth. The total number of people affected by floods worldwide over the past two decades is estimated to be about 2.4 billion, according to the United Nations Office for Disaster Risk Reduction (UNISDR). According to the report published by the Centre of Research on the Epidemiology of Disasters (CRED), which describes the disaster figures in the last two decades, floods in disasters between 1998-2017 was the disaster type that affected the most people in other species in the world, even if it did not result in death by 45%. The negative effects of climate change, which affects climatic conditions all over the world and is a global problem, cause flood risk to become a growing problem today. Global warming due to the effects of climate change, change in rainfall and consequent sea level rise are causing struggle with floods in many countries around the world. According to the World Bank, the number of global flood events worldwide has steadily increased over the past sixty years due to the negative effects of climate change. According to data published by UNISDR, worldwide only floods in 2018 affect more than 91 million people, causing $ 37 billion in damage. The ongoing rapid urbanization process and the negative effects of climate change in floods worldwide can be said to be leading factors. Even worse, according to statistics, the impact of flood events on societies and economies is predicted to increase further in the future due to population densities and increased economic activity due to the pace of urbanization across rivers, seashores and oceans worldwide. Annual maximum discharges of major rivers due to global warming are expected to increase by 3% to 9% by 2050, which could lead to more severe coastal floods.
The negative effects of flood risk on both communities and the economic structure and the fact that it poses a greater threat in the future due to global warming make it necessary to take particular interest in the concept of flood risk management and make the rationale for writing the thesis in the context of this issue.
Although flood risk is considered to be a natural risk factor and the risk factors is tried to be controlled by various measures, the measures taken and the perspective of flood risk have changed over time and experienced various breakdowns. The fact that countries around the world have experienced major flood disasters in the last half century and experienced that the existing flood protection approaches are inadequate has revealed the need for new flood protection approaches. Until the 1990s it was generally based on hard engineering solutions and included levees, seawalls, dykes, reservoirs, barriers, attenuation tanks, bypass/evacuation channels, flood detention, etc. although it has been attempted to reduce flood risk by using particle applications based on the construction of such structures, the transition from flood control approach to "flood risk management" approach has been experienced because these methods do not provide sufficient protection to manage flood risk and can cause environmental damage. Instead of focusing on only the single dimension of flood control, this approach seeks to address the wide range of negative consequences caused by floods, and comprises more non-structural or ecologically based and multi-perspective/ holistic approach solutions, such as wetland and rivers restoration, river and coastal basin management, sustainable drainage systems, and flood risk reduction based on spatial planning implements, rather than structural measures. The flood risk management approach includes an approach that addresses damage to communities and economies  reducing vulnerability (vulnerability mitigation), and thus addressing flood risk to include social, economic, and environmental considerations, rather than simply preventing the threat posed by floods (hazard mitigation). This paradigm shift in flood risk mitigation methods has gradually begun to take place in the solution approaches of different countries around the world, and the flood risk management approach in the world has shifted from the non-integrated measures based solely on hard engineering solutions, to a point that includes non-structural and ecologically based, multi-perspective /holistic measures and implements of these measures through spatial planning tools.
The aim of this thesis is firstly to examine changing flood risk management approaches of these countries by explaining the driving factors behind the changing paradigm of flood risk reduction policies in the changing framework of the World; to examine the changing flood risk management approaches of these flood-exposed countries through determined criteria and to define the role of spatial planning implement within the changing framework of the concept of flood risk management.
The city of Edirne, which is examined as a case study within the scope of the thesis, is located at the intersection of Meric, Tundja and Arda Rivers due to its geographical location. The city of Edirne has been affected by various flood disasters throughout history, as the watershed borders of the Meric, Arda and Tundja Rivers also cover Bulgaria and Greece, and the riverhead are under the control of these countries. Especially projects have been developed in Edirne by making various international treaties with border countries to protect the city center from flood risk and various measures have been developed to reduce flood risk by the State Hydraulic Works (DSI), which is the main organization responsible for flood risk management in Edirne. Thanks to the flood warning system developed within the scope of the "Capacity Development for Flood Forecasting and Flood Control Project" between Bulgaria and Turkey, the amount of rainfall that will fall in the Meric Basin can be determined in advance and the required measures can be taken by estimating the flood that may cause excessive rainfall flow within 1-2 days. Although the flood warning system prevents the loss of life in areas that may be flooded, it is not able to create an adequate solution alone because of the economic losses caused by the flood. Following the last re-experiencing of the economic losses due to the flood in 2015, the Karaağaç Evacuation/ Baypass Channel, which is 7800 m long and capable of discharging 773 m3 of water, was built by Edirne DSI 11th Regional Directorate. It is thought that this channel will increase the flow rate of 1700 m3 calculated according to the current Q500 maps of the Meric River to 2500 m3 and prevent possible floods due to the increase of the flow rate of the river.
Many countries around the world have experienced over the years that flood risk mitigation measures based on hard engineering solution such as bypass/evacuation channel or levee constructions are workarounds and do not provide adequate protection alone and there has been a shift from the flood control approach based on hard engineering solution to the flood risk management approach, which involves managing risks through spatial planning tools rather than through hard engineering solutions. The second aim of this thesis is to examine the paradigm shift within the scope of the thesis, whose accuracy will be tested by examining the world samples, with spatial planning tools within the framework of Edirne's flood risk reduction methods, and to compare the world samples and sample case study area Edirne's flood risk management approaches.
With the publication of internationally recognised directive such as the EU Water Framework Directive (WFD) and Flood Directive issued by the EU, it has been recognised that the way rivers are used and managed needs to change and the importance of moving beyond flood defence approaches, which are economically costly and ecologically unsustainable, but also have many shortcomings associated with water and land use planning, has been highlighted. The context of flood risk management of Edirne has been evaluated primarily within the framework of relevant legal instruments, which are considered as spatial planning implements and are the implementing tools of flood risk reduction policies. Due to the fact that the Meric, Tundja and Arda rivers that cause flood in Edirne are within the scope of waters that cross international borders, within the framework of the relevant legislation, firstly international transboundary water policies and related legal instruments such as the European Union WFD and Flood Directive were evaluated. Secondly, the structure of Turkey's flood related legislation on national scale was examined and in this context; Spatial Plan Formation Regulation, the Law on Protection Against Flood Waters and Flood No. 4373, The Basic Geological, Geological-Geotechnical and Micro-zoning Survey Circular letter No. 10337, the Legislation on Preparation, Implementation and Monitoring of Flood Management Plans, the Legislation on Preparation, Implementation and Follow-up of was examined.
Following the context of the issue, which has been discussed within the framework of international and national legislation, the existing plans, starting from the regional scale of Edirne in Thrace region and up to the local scale, have been evaluated within the framework of flood risk management policies. TR21 Trakya Region 2014-2023 Regional Plan, 1/100.000 scale Trakya Sub-regional Ergene Basin Revision Environment Plan, Ergene Basin Protection Action Plan (EHKEP), Meric-Ergene Basin Management Plan, Edirne Municipality Strategic Plan, 1/25.000 scale Edirne Provincial Environment Plan, 1/25.000 scale Edirne (Central) Environmental Plan, 2019 Regional Flood Plan and 1/5000 scale Master Development Plan are examined existing plans in this context. The point to be noted here is to examine the consistency of spatial plans in Edirne in terms of plan decisions and related legal instruments and to evaluate these spatial plans within the framework of flood risk management policies; at the same time to determine if there is a mismatch between spatial planning implements and flood risk management policies.