Kentsel ulaşım planlamasında (KUP) arazi kullanım-ulaşım etkileşiminin modellenmesi : İstanbul üzrerine bir değerlendirme

Abstract

Kentsel Ulaşıra Planlaması (KUP) Süreci, arazi kullanım fonksiyonları ile ulaşım problemleri arasındaki etkileşimin fark edilmesiyle giderek daha çok üzerinde durulan bir konu olmaktadır. Özellikle hızla büyüyen kentsel alanlarda karşılaşılan ulaşım problemlerine yönelik, planlı ve programlı arazi kullanım-ulaşım ilişkisinin kurulması gerekmektedir. KUP süreci içinde yaygın olarak kullanılan planlama yaklaşımı, ulaşım talebinin modellenmesine yönelik olan dört-adımlı modelleme yaklaşımıdır. Kentsel Ulaşım Mode Hemes i (KUM) ' inde ulaşım talebinin modellenmesi uygulamaları öncelikle gelişmiş ülkelerde yer almış ve KUP süreci içinde önemli yer taşımıştır. Günümüzde KUP süreci içinde arazi kullanımı-ulaşım etkileşiminden ortaya çıkan uzun-dönem ilişkilerin değerlendirilmesi, dengeli ve sürekliliği olan planlama yaklaşımının gerçekleştirilmesi için giderek daha çok önem kazanmaktadır. KUP uygulamalarının ulaşım talebine etkileri yanında, kentsel gelişmeyle paralel olarak arazi kullanımlar hatta diğer ulaşım sistemleri üzerinde de etkisi olabilmektedir. Bu çalışmada, İstanbul örneğinde kentin mekansal gelişmesi üzerinde rol oynamış ulaşım sistemlerinin kentsel gelişme üzerindeki etkileri değerlendirilmektedir. istanbul'da kamu toplu taşıma sistemlerinden İETT, raylı sistem (banliyö, metro, tünel ve tramvay) ve denizyolları (şehir hatları ve deniz otobüsleri) nin erişme noktalarının ketsel gelişme üzerindeki etkisi araştırılmıştır. Bunun yanında ulaşım ile ilgili uzun-dönem etkileşimde, E- 5 ve TEM yollarıyla bağlantılı I. ve II. Boğaz köprülerinin mekansal gelişme üzerindeki etkileri değerlendirilmektedir. Mevcut durumdan elde edilen sonuçlar ile, III. bir karayolu geçişi olmasının kentin mekansal gelişmesine ne şekilde yansıyacağı karşılaştırmalı olarak değerlendirilmektedir. Elde edilen sonuçlara bağlı olarak İstanbul'un KUP süreci içindeki planlama stratejilerinin değerlendirilmesi yapılmaktadır.

The continuous increase in urban transportation problems has necessitated new approaches and techniques in the Urban Transportation Planning (UTP) Process. The awareness of the interaction between land-use and transportation has brought new planning procedures in the urban development areas, that are growing very rapidly. Particularly in developing countries facing rapid urban development, the planned and programmed relationship of urban land-use and transportation is necessary to be built for better development of these two ma j or components. In the UTP process, the more common planning approach is on travel demand modelling which is known as four-staged modelling. Initially in the UTP process, the travel demand modelling applications took place in developed countries. In the end of the UTP process, the short-run relations like travel demand were most common subject to be dealt with. But afterwards, the long-run interactions and affects of transportation and land-use have gained importance to achieve the balanced and sustainable planning approaches. UTP applications can affect land-use functions in conjuction with urban development and also other transportation systems as well as travel demand. The aim of this study is to determine the policies and strategies which have to be considered to achieve balanced and sustainable urban development, by evaluating the interaction between urban land-use and transportation. By investigating the procedures of UTP and its sub-section Urban Transportation Modelling (UTM) in the case of Istanbul, the I.st and the Il.nd Bosphorus Bridges which have important role on the physical urban development form, is evaluated to make some estimations of long-run effects on XI urban land-use and transportation interaction for future bridge proposals. The study consists of five main chapters. After the introduction, the interactions between the land-use and transportation which are the main components of the UTP system are dealt with in the following order land use- transportation, land use-traffic, land use-transportation- environment and land use-land values-transportation. The third chapter begins with the traffic functional transportation planning process where transportation is accepted as a function of urban land use. Continuing with systems-comprehensive planning approach and finally concluding with the developmental approach. In the systems approach, transportation is assumed as a component of the all system, and mentioned that transportation must be planned with all other functions of urban system. But in reality, many urban transportation applications that have occurred in this era shows that the UTP process is unfortunately limited with travel demand interactions. In this chapter, all processes also have some limitations in their structures. As a result of this every procedure has effected the next stage. The last process, the Developmental Planning Approach is very new and applicable to developing countries which as yet have not completed their urban, regional and national development processes. In this approach, transportation is accepted as a tool to direct the urban development. Thus, when urban development is regulated, the regional and national development will be taken under control. As this approach is very new and only preferred for developing countries, it has some difficulties and some operational problems to be solved. The main interactions occurring in the land use- transportation system are explained with Manheim' s figure in the fourth chapter. The components and the relationship between them can be seen in this figure. The system is described with the relationship between Activity System (A), Transportation System (T) and the interaction between the two as Flows(F) by Manheim( 1979) (Figure. 1). By using this figure, modelling of interactions can be classified as:.Modelling of the short-run interactions and.Modelling of the long-run interactions. XII Figure. 1 The Basic Interactions Between Components of the System (Manheim, 1979) The modelling of the short-run interactions is evaluated by travel demand modelling, this is the most common approach in the UTP process which is called the four-staged modelling approach. The first interaction (1) symbolizes the relationship between the activity system and the transportation system in the short-run period. The relationships numbered 2 and 3 symbolize long-run interactions. The four-staged modelling is the most developed part of the Urban Transportation Modelling (UTM) process. In this sub section, the modelling steps used in four-staged modelling are described in the order of trip generation, trip distribution, modal split and traffic assignment. By the developments on the UTM process, these four-staged sub models have had concurrent improvements in their structures. They have had a more comprehensive approach and the data used in modelling has changed from aggregated based to disaggregated structure. At the end of the sub-section of modelling of the short-run interactions, the Incremental Four-Stage Model of London is given as an example to this approach. XIII Modelling of the long-run interactions between system components is evaluated by reviewing land-use location models, land values modelling and comprehensive modelling approach which consists of either travel demand or land-use and land values modelling techniques. In this sub-section, some examples of the long-run impacts of land use- transportation interactions are given. In these examples some transportation implementations and applications are investigated with their long-run impacts on land-use functions. The examples investigated include the impact of the Los Angeles metro railway construction on land values, the impact of the Houston transitway system on land-use, the impact of Minnesota highway connections on economical development and in the Santiago case the impact of transportation investments on land values. At the end of this sub-section, the comprehensive modelling approach is evaluated to be used as a basic tool on long-run impacts of land use-transportation interactions. Within the scope of all the conceptual evaluations, the fifth chapter deals with the development of the UTP process and the modelling of long-run interactions between land-use and transportation for Istanbul. In the case study of Istanbul, the studies applied on the development of UTP or UTM processes have been reviewed by giving importance to the I. s t and Il.nd Bridges as well as the connected highways TEM (Trans European Motorway) and E-5. Due to the accelerated urban growth and the dispersion experienced in the 1950' s together with the fact that the main UTP studies on the Bosphorus crossings took place after the 1950' s, the data gathered for modelling of long-run impacts start with the year 1955 in the border of the Greater Municipality of Istanbul from Pendik to Küçük Çekmece Counties. The Adalar County has been excluded from the evaluations as it does not have a direct connection with the highway system. In the evaluation of the UTP process, four terms have been studied: 1-1950-1965, 2-1965-1975, 3-1975-1985 and 4-1985 until the present day. The basic view of emphasizing on the evaluation of the UTP process in Istanbul is to determine the impacts of XIV transportation applications whether implemented or not by taking into account the land-use development. The aim of this study is to evaluate UTP and UTM processes for Istanbul by giving importance to the long-run impacts of the Bosphorus crossings and their connecting highways on physical dispersion of land uses, then to model the impacts according to the existing interactions between land-uses and transportation variables for estimating the future impacts of another Bosphorus crossing proposals. The data used in the evaluation of the models of the long- run impacts is listed below: 1-The data on land-use; i ) Measurements of the built-up area of counties for the years 1955, 1965, 1975, 1986 and 1993 (Figure. 2), ii)The population growths of counties for the years 1955, 1965, 1975, 1985 and 1990 (State Institute of Statistics-SIS, General Population Counts), iii) Household numbers of counties for the years 1985 and 1990 (SIS, General Population Counts), iv) Employed population numbers of counties for the years 1985 and 1990 (SIS, General Population Counts), v) Population densities of counties for the years 1955, 1965, 1975, 1985 and 1990 (population/km2, SIS, General Population Counts), vi) Total building and house numbers of counties for the years 1974 and 1984 (SIS, Building Counts Statistics) and vii) Medians of land m2 unit values of counties for the years 1986 and 1994 (TL and $ based). 2-Data on the transportation system; i)Line distances of the railroad system in counties for the years 1955, 1965, 1975, 1985 and 1993 (railways, tunnel, light rail and tramway), XV B Built-up Areas ? lndusnal Areas 3 Border of Greater Istanbul Municipality E3 County Border A21ME TEZER (1955) ?B Built-up Areas ? Jndusrial Areas Q Border of Greater Istanbul Municipalir E3 County Border Azime TEZER (1965) M Built-up Areas ? lndusnal Areas S Border of Greater Istanbul Municipality E3 County Border E3 £-5 Motorway Azime TEZES (1975) [ M Built-up Areas j ? lndusnal Areas ; E9 Border of Greater istanbul Municipality ! hJ County Border. S Motorwav «fj E-5 Motorway P*4 TEM Motorway psj Nefhern Proposal of Ill-rd Bridge (iu Southern Proposal of IH.rd Bridge Figure. 2 Built-up Area Development of Istanbul in 1955 to 1993, the Existing and the Proposal Bridges on Bosphorus XVI ii) Total access point (i.e. station) numbers of the rail road system in counties for the years 1955, 1965, 1975, 1985 and 1993, iii)İETT bus-stop numbers in counties for the years 1955, 1972, 1978, 1982 and 1991 (Line maps of ÎETT), iv) Ferry and sea-bus port numbers in counties for the years 1955, 1965, 1975, 1985 and 1993 (Istanbul Ferry Lines Management), v) Total access point numbers of all transportation systems in counties for years of 1955, 1965, 1975, 1985 and 1993 (station-stop-port), vi) Accessibility densities of counties for the years 1955, 1965, 1975, 1985 and 1993 (total access points/service area-county area) and vii) According to existing transportation systems or geographical locations, the level of centralization situations of counties in the years of 1955, 1965, 1975, 1985 and 1993. 3-Dummy variables group; i)Year variables of 1955, 1965, 1975, 1985 and 1990 (For the year in question the value is 1 for the other years it is 0), ii)I.st and II. nd Bridge variables (In all cases after the date of operation it takes 1, for other years it is 0) and iii)Road-l (E-5) and Road-2 (TEM) variables (Since the date of construction the counties for which the highway passes through have a value of 1, the counties for which it does not pass trough have a value of 0). Using all the variables mentioned above, the long-run interactions have been tested in the SPSS statistical program. Three types of land-use functions were emphasized in investigating the long-run impact of transportation on land- use development. The first emphasized land-use function is on the built-up area development as a dependent variable and XVII tried for all time periods between 1955 to 1993. The second emphasized is population densities and has been tested for all periods. The last dependent variable is on land values and has been tested for the last two periods 1985 and 1993. Linear multiple regression modelling is used to evaluate the impact of explanatory variables on dependent variables (i.e. built-up area, population density and land value). After many tests, the most appropriate formulae on these three land-use functions were used to estimate future land use as well as transportation values according to different land-use functions and different bridge crossing proposals for the year of 2010. Two different bridge crossing proposals were tested on the development of new built-up area and population densities of districts. As a result of built-up area model, the very important component of Istanbul's sustainable development, approximately 8800 hectares of the forests will be under danger of new built-up area development. The second bridge proposal is the one which passes through Bosphorus between the two existing bridges. As a result of the population densities model, there will be rise on the population densities in Ümraniye, Üsküdar, Kadıköy, Beşiktaş, Kağıthane, Şişli and Beyoğlu districts. Finally, the impact of new rail-system for the year 2010 on land values is tested with the land values model for the districts being effected. As a conclusion of this study, the developmental transportation planning process must be improved on operational scale for Istanbul. To achieve balanced and sustainable urban development, the transportation proposals must be evaluated as a tool which leads to urban development.