Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
TRANSIT-ORIENTED DEVELOPMENT IN A HIGH-DENSITY CITY: IDENTIFYING ITS ASSOCIATION WITH TRANSIT RIDERSHIP IN SEOUL, KOREA (CASE STUDY REPORT) Course Title: Urban planning legislation Instructor: Dr. Yasser Mahgoub Academic Semester: Fall 2015 Student Name: Najeeba QU ID: 201405617
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
TABLE OF CONTENTS 1. INTRODUCTION ................................................................................................................. 2 2. RESEARCH DESIGN ........................................................................................................... 2 2.1. Research Background,Boundaries And Data ................................................................. 2 2.2. Methodology And Process ............................................................................................. 3 3. ANALYSIS,RESULT AND DISCUSSION ......................................................................... 3 3.1. TOD planning factors and daily ridership .................................................................... 3 3.2. TOD planning factors and modal ridership .................................................................. 4 3.3. TOD planning factors and Temporal ridership............................................................. 4 4. APPLICATION OF TOD PLANNING FACTORS ............................................................. 5 4.1. Transit supply and operations characteristics ............................................................... 5 4.2. Land use characteristics ................................................................................................ 5 4.3. Street network and urban design characteristics........................................................... 5 5. CONCLUSION AND POLICY IMPLICATIONS ............................................................... 6 5.1. Transit supply characteristics ....................................................................................... 6 5.2. Land use characteristics ................................................................................................ 6 5.3. Street network and urban design characteristics........................................................... 6 6. REFERENCES ...................................................................................................................... 7 7. APPENDIX ............................................................................................................................ 8
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
1. INTRODUCTION Traffic congestion, environmental degradation, social impedance and spatial integration are some of the problems created by urban sprawl in many countries. It is assumed that traditional land use patterns are regarded as means to address these issues. These land use patterns include high-density development, mixed use, and pedestrian-friendly urban design, near transit centers. The planning method of transit-oriented development (TOD) developed by American planner Calthrope (1993), has been used as a solution to tackle problems of traffic congestion. This concept tackles the problems resulting from disconnect between urban development and transportation (Sung & Oh, 2010). TOD is a planning technique that aims to reduce automobile use and promote the use of public transit and human-powered transportation modes through high density, mixed use, environmentally- friendly development within areas of walking distance from transit centers. According to Cervero & Kockelman (1997) most of the TOD planning principles revolve around increasing development density (density), promoting mixed land uses (diversity) with pedestrian-friendly urban design (design) near transit centers. According to the study, TOD is considered as a key planning method in Seoul, Korea to address the key issues of traffic congestion and land resource consumption. The analysis and examination using TOD can create a solid tool for the general public and policy makers in resolving the traffic problems. This shows the importance of legislations in developing a successful design. The study focuses on the distributional patterns and characteristics of planning factors such as transit supply service, land use, street network and urban design at 214 rail station areas in Seoul. Casual method of analysis was conducted utilising multiple regression analysis models determining the relation between TOD factors and transit ridership. These were differentiated at the levels of time of day, day of the week, and transit mode at the respective rail station areas. The report summarises the factors effective in promoting transit ridership through characteristics of planning from preliminary studies and the results of regression analysis. It identifies the relationship between TOD planning factors and transit ridership effective in creating transit-oriented cities. The conclusion reveals the factors effective in formulating policies for a transit centered city around a rail station. 2. RESEARCH DESIGN 2.1 Research background, boundaries and data The study is focussed on city of Seoul, Korea with an area of 603.3 km2, population of 10.4 million residents and density of 17,127 person/km2.The TOD planning factors were derived from the studies on western cities and implemented in the case of high density city like Seoul. A preliminary empirical study highlighted that 3D planning factors along with considerations for distance and accessibility to transit could only achieve TOD. Cultural differences also affect the level of application of these factors (Lin & Shin, 2008). One of the first attempts included Rosario’s concept introduced by Kang in 2000 to solve traffic congestion and consumption of developable land. It called for concentrating housing supply
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
within 1km radius of rail stations along all railway lines (Figure 1). This solved the issue of housing prices and supply shortage but increased travel distance and automobile use. Seoul demonstrated diverse type of rail station areas such as residential-oriented, mixed use oriented and employment oriented. This lead to the study of relation between transit ridership and planning factors. The study boundary constituted the urbanized rail station areas within 500m radius of a rail station (Figure 2).The study was conducted around 214 stations with data obtained from diverse sources managed by local transit agencies and central-local governments. The data used states that public transit is widely used by citizens covering 66.3% of the total trips among which 38.5% is via railways and 27.8% by bus. The average daily traffic speed on the major arterial roads was noted as lower than 20 km/hr. The transit ridership data were obtained using smart card matching techniques. These data determine the mode of transit used, time of the day and the transfers taken by the people. Data regarding the railways and stations were obtained from urban railway plans. GIS maps were used to track the bus services operating within the rail station areas. Land use and urban design data were obtained from the national transport databases. Then, further analysis was done using regression models. 2.2 Methodology and process The methodology involves the analysis using multiple linear regression models identifying relation of dependable variables like time of day, day of week etc. with explanatory variable such as transit services, density, diversity and urban design factors (Figure 3). Depending on the travel purpose and urban spatial structure, transit ridership is classified into weekday and weekend, bus and rail, peak hour and non-peak hour, and alighting and boarding (Figure 4). The relation between the temporal patterns and the TOD planning factors are identified by utilising daily, modal and temporal ridership as dependable variables. For the purpose of analysis the following determinants were analysed: 1. The daily transit ridership determined by boarding volume of the day. 2. The modal transit ridership determined by on board ridership for bus, rail and transfer trips. 3. The temporal ridership determined by boarding and alighting during the morning peak time (7 AM–9 AM) and morning non-peak time (9 AM–12 PM). The three TOD planning factors are measured by relating each of these factors to dependable variables. These variables are checked for any overlap through correlation and multicollinearity tests. Thus, any overlapping variables are removed prior to analysis. Finally, the TOD factors for analysis were represented by 20 variables (Table 1). 3. ANALYSIS RESULT AND DISCUSSION 3.1 TOD planning factors and daily ridership According to the study, weekday and weekend transit ridership corresponds to the every-day purpose and leisure purpose pattern of using the rail station area. A difference in the influence of the TOD planning factors (statistical significance, directionality and intensity of influence) within the weekday and weekend analysis raises the necessity to introduce different TOD planning factors depending on the type of rail stations.
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
The planning factors that increase both weekday and weekend transit ridership in terms of public transit development include: an increase in number of bus lines and bus stops, shorter headway and greater distance between the neighbouring stations. The weekday ridership is positively affected by a large number of short distance bus lines and stations. From the regression analysis models it is clear that in terms of land use planning factors both the weekday and weekend ridership are influenced by higher residential density as these areas serve as trip originators. The weekday ridership is high in areas of office buildings whereas weekend ridership is high in areas of retail and commercial buildings. The weekend ridership increases with the higher land use mix index of four land uses-residential, commercial, business and others. The commercial and business mixed uses have no significant impact on ridership. The TOD planning factors of design characteristics influence the ridership to a great extent. The weekend and weekday transit ridership increases with the increase in four-way intersection density and average building area. The weekday ridership is further influenced by road length and average building complex area while a cul-de-sac with a higher density increases the weekend ridership. Table 2 summarises the result of TOD planning factor and daily ridership. 3.2 TOD planning factors and Modal ridership This analysis result determines the effect of TOD planning factors on ridership utilising the onboard ridership for bus, rail and transfer trips. The transportation supply characteristic factors such as the number of bus lines, headways, the number of bus stops, and the distance between stations influence the rail, transfer and bus ridership. The rail transit is influenced by the number of station exits, accessibility to the regional subway, and the percentage of driveways on streets. Notably, a greater accessibility to a regional subway increases the use of the subway. In terms of land use patterns the factors of residential density and the four-land-use mix index play an important role. The use of rail transit is reduced by higher driveway percentage. Due to the availability of driveways, the use of automobiles are encouraged reducing the dependency on rails. From the analysis, the use of subways and transfers are promoted in areas of high residential density and land-use mix index. An increase in the development density further increases the rail transit ridership. Certain characteristics of street networks and urban design prove a negative effect on rail transit ridership. A rail station area with a greater road length, a greater driveway percentage, and a higher average building complex area lowers the use of rail transit. Table 3 summarises the dependency result of TOD planning factor and modal ridership. 3.3 TOD planning factors and temporal ridership A multiple regression model reveals the factors responsible for increased ridership in residential, employment and shopping rail station areas at different times of day. The study highlights that during the peak time (7AM-9AM) the vehicle boarding distribution in residential oriented rail station areas and the vehicle alighting distribution ratio in employment centered areas is high. The vehicle alighting ratio is high in the shopping oriented areas during the non-peak time (9AM-12PM).
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
The residential-oriented transit ridership increases with greater residential density; the employment-oriented transit ridership rises with greater employment density; and the shopping-oriented transit ridership climbs with greater development density of commercial or business facilities. The land-use mix index generally increases the ridership. Good regional subway accessibility decreases the rail ridership obtained from the lower morning peak-time boarding. Similarly, the morning peak-time alighting in rail station areas within an employment - centerd area is low. On the contrary, non-peak-time boarding numbers tend to have a statistically significant influence at the station- influence areas with high employment accessibility. The four way intersection density influences ridership regardless of the time of day. The number of morning peak boarding highlights the influence of average building group floor area with positive effect on transit ridership at rail stations. Table 4 summarises the dependency result of TOD planning factor and modal ridership. 4. APPLICABILITY OF TOD PLANNING FACTORS The results obtained from the regression analysis at Seoul’s rail station areas can be summarised as follows (Table 5): 4.1 Transit supply and operation characteristics A higher degree of transit operation and service provision increases the rail transit ridership. The ridership-dependent supply services such as the number of bus routes or the headways may negatively influence transit ridership. Hence, the ridership-fixed supply characteristics can be efficiently used in policy formulation such as the number of bus stops, the distance between stations and the number of existing stations. 1) The fact that greater distance between stations increases the ridership can be considered as a planning factor to develop a construction plan for light rail transit or future expansion of the railway network. 2) The number and location of bus stops can also be a critical planning factor. 3) Moreover, the number of existing stations can be a planning factor in increasing transit ridership through the improvement of pedestrian accessibility and transfer convenience. 4.2 Land use characteristics Higher development density in the rail station areas can be used as development policy as they generate higher transit ridership. The development densities of residential and business facilities over business facility development also contribute to increased ridership in rail areas. The studies conclude that high land use mix index is a crucial planning factor. The increase in accessibility through downtowns and regions prove to be an effective policy. In addition to the above, non-residential, commercial and business mixed use indexes can hamper the development of policies for rail transit ridership. 4.3 Street network and urban design characteristics The fourway intersection density and building design factors play an important role in the policy formulation. One of the policy formulations that can influence the rail transit ridership include promotion of a high four-way intersection density, involving a pedestrian friendly,
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
narrow, grid-type street network system. Excessive use of the grid pattern discourages ridership. The increase in the transit ridership due to the grouping of buildings such as apartments or schools constructed as a single usage forms a factor for policy making. Hence, policies can be formulated around the need for orientation of the building complex design providing clear access to pedestrian paths. The study implies that a high driveway percentage at rail station areas reduces ridership for rail transit and residential centerd areas. Policy formulations supporting reduction of percentage of driveways need to be promoted while considering rail station area or intermodal transportation system development plans. 5. CONCLUSIONS AND POLICY IMPLICATIONS The study of dependency of transit ridership on TOD planning factors in Seoul suggests that these planning factors can be applied in a lower density city like Doha. This suggests that the TOD planning factors can be successfully applied in the development of rail station areas inducing a transit centerd city. From the analysis, three major strategies in addition to attainment of density include: Enhancement of transit center function, diversification of land use and considering pedestrian-friendly road networks and urban designs. 5.1 Transit supply characteristics To create a more transit-oriented city, the quality and quantity for intermodality between bus and rail transit services within rail station areas should be considered. The quality and quantity of the transit services should be combined with the 3D (Density, diversity and design) planning factors to achieve the objectives of relieving traffic congestion and consumption of fewer land resources. Designing of easy transfer between the bus and rail service would effectively increase the transit ridership in high development densities. Thus, generating better connectivity between the different modes around a transit center is an effective policy in an area around rail stations. 5.2 Land use characteristics Mixed land use pattern near a transit center is an effective policy in attracting transit users. The mixed land use pattern shows the same effect as high density development however does not pose the problem of increasing congestion. Hence, the former can be used as a better strategy. The mixture of residential and non-residential uses promotes more ridership as compared to mixture between non-residential uses. This strategy is against the market economy principle. To induce mixed-use land development providing density bonus as an incentive would effectively attract more transit users around a transit center, such as a rail station. 5.3 Street network and Urban design characteristics Urban design factors such as grid-type road networks, narrow streets and pedestrian friendly design prove to be positive planning factors. These approaches reduce automobile use by reducing the traffic speed and enhancing pedestrian accessibility to a transit center. Reduction in the total road length, percentage of driveways and road width increase transit ridership. Certain factors of planning depend on the location. A TOD can also be created by increasing the number of four way intersections and decreasing cul-de-sacs. The difference in the urban growth pattern of the cities determine the relevancy of these factors.
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
6. REFERENCES Sung, H., Oh, J. (2010). Transit-oriented development in a high-density city: Identifying its association with transit ridership in Seoul, Korea. Cities, 28(1), 70-82. doi: 10.1016/j.cities.2010.09.004 Calthrope, P. (1993). The next American metropolis: Ecology, community, and the American dream. Princeton Architectural Press. Cervero, R., Murakami, J. (2010). Rail and property development in Hong Kong:Experiences and extensions. Urban Studies, 46, 2019–2043. Cervero, R., & Kockelman, K. (1997). Travel ridership and the 3Ds: Density, diversity,and design. Transportation Research D, 2(3), 199–219. Taylor, B., D., Fink, C., N., Y. (2010). The Factors Influencing Transit Ridership: A Review and Analysis of the Ridership Literature. Habitat International, 45, 156- 162.
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
7. APPENDIX
Figure 1: Rosario’s Concept. (Source:Kang,1993)
Figure 2: Study boundary. (Source:Cities,2010)
Figure 3: Methodology and process
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
Figure 4: User rider characteristics EXPLANATORY VARIABLES FOR TOD PLANNING FACTORS 1 Number of bus route 2 Average headways Bus 3 Number of short bus route Transit supply characteristics 4 Number of bus stops 5 Distance between stations Railway 6 Number of station exists 7 Residential density Density 8 Commercial density 9 Business density Land use 10 Land-use mix index for four land uses characteristics Diversity 11 Commercial/business mix index 12 Three downtown subway accessibility Regional accessibility 13 Regional subway accessibility 14 Total road length 15 Average road width Street network 16 Percentage of drive way Design 17 Four-way intersection density characteristics 18 Dead end road 19 Average building group Building design 20 Average area of each building Table 1: Explanatory variables for TOD planning factors.
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
TOD PLANNING FACTORS AND DAILY RIDERSHIP Increase/decrease in (X) Planning factors Dependable variables (X) promotes transit ridership Number of bus route Increase Average headways Decrease Bus Number of short bus route Decrease Transit supply characteristics Number of bus stops Increase Distance between stations Increase Railway Number of station exists Residential density Increase Density Commercial density Land-use mix index for four Increase land uses Land use Diversity Commercial/business mix characteristics Decrease index Three downtown subway Regional accessibility accessibility Regional subway accessibility Total road length Average road width Percentage of drive way Street network Decrease Design Four-way intersection density Increase characteristics Dead end road Average building group Building design Average area of each building Increase Table 2: Daily transit ridership and TOD planning factors. TOD PLANNING FACTORS AND MODAL RIDERSHIP Increase/decrease in (X) Planning factors Dependable variables (X) promotes transit ridership Number of bus route Increase Average headways Bus Number of short bus route Transit supply characteristics Number of bus stops Increase Distance between stations Increase Railway Number of station exists Increase Residential density Increase Density Commercial density Land use Land-use mix index for four characteristics Increase land uses Diversity Commercial/business mix index -
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
Regional accessibility
Design characteristics
Street network
Building design
Decrease Decrease Decrease Decrease Increase
Three downtown subway accessibility Regional subway accessibility Total road length Average road width Percentage of drive way Four-way intersection density Dead end road Average building group Average area of each building
Table 3: Modal transit ridership and TOD planning factors. TOD PLANNING FACTORS AND TEMPORAL RIDERSHIP Increase/decrease in (X) Planning factors Dependable variables (X) promotes transit ridership Number of bus route Increase Average headways Decrease Bus Number of short bus route Decrease Transit supply characteristics Number of bus stops Distance between stations Railway Number of station exists Residential density Increase Density Commercial density Increase Land-use mix index for four Increase land uses Land use Diversity characteristics Commercial/business mix index Three downtown subway Regional accessibility accessibility Regional subway accessibility Decrease Total road length Decrease Average road width Decrease Percentage of drive way Street network Decrease Design Four-way intersection density Increase characteristics Dead end road Average building group Building design Average area of each building Increase Table 4: Temporal transit ridership and TOD planning factors.
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Case study Report I Urban planning Legislations
associationdevelopment with transitinridership in Seoul, Korea Transit-oriented a high-density city: Identifying its association with transit ridership
TOD PLANNING FACTORS AND MODAL RIDERSHIP Planning Increase/decrease in (X) promotes Dependable variables (X) factors transit ridership Increase Number of bus route Decrease Average headways Bus Decrease Number of short bus route Transit supply characteristics - Increase Number of bus stops - Increase Distance between stations Railway - Increase Number of station exists Increase Residential density Density - Increase Commercial density Land-use mix index for four Increase land uses Land use Diversity Commercial/business mix characteristics - - Decrease index Three downtown subway - - Regional accessibility accessibility Decrease Regional subway accessibility Decrease Total road length - Decrease Average road width Street network Decrease Percentage of drive way Design Increase Four-way intersection density characteristics Dead end road - - - Decrease Average building group Building design Increase Average area of each building Table 5: Applicability of TOD planning factors.
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