Reducing the Burdens of Mobility by Sustaining the “Dimension, Density, Diversity” Triangle. The Bangkok Example

1. Introduction

Pollution, congestion, and accidents are the most prominent problems associated with urban transport, more specifically with road traffic and motorised vehicles. Urban planning that serves mainly the needs of car travel and prioritises road infrastructure financing is regarded as the main cause of the “urban mobility crisis” prevalent in most of the larger cities. [^[1] ] In contrast, successful large cities have eased the burdens of mobility by integrating land use and transportation planning, thus matching urban form with transport systems. They have enhanced the traditional characteristics of cities which “are size, density and diversity.” [^[2] ] While the benefits of size (dimension) need to be critically assessed, the benefits of high density and diversity levels are obvious, especially regarding sustainable transport: High densities reduce travel distances, and high diversity means a greater variety of infrastructure and services easily accessible, again reducing travel distances. This paper will transfer these insights to the transportation system of Thailand’s capital city of Bangkok and then develop recommendations for implementation.

2. Sustainable transportation planning and the basic characteristics of cities

Urban mobility contributes to major global and local problems (see table 1), also called externalities or “burdens of mobility”; at the same time it is also affected by them (“burdens on mobility”). [^[3] ] Yet, due to their characteristic features – density, dimension and diversity – cities can be the ideal form of settlement to achieve sustainable development. [^[4] ] This is especially true for the transportation sector because cities can design transport systems in a more sustainable way than other forms of settlements. Due to their characteristic features – density, dimension and diversity – they can reduce transport needs and impacts without compromising mobility and flexibility needs: while dimension and diversity guarantee the availability of a high variety of urban facilities and services, high densities guarantee their accessibility. Together all three characteristics reduce travel distances, a main requirement of sustainable urban transportation, which “[...] involves the provision of accessibility and the generation of wealth by cost-effective and equitable means, while safeguarding health and minimizing the consumption of natural capital and emissions of pollutants.” [^[5] ] The following principles form the basis of sustainable urban transportation planning:

1. Urban structure that minimises travel distances [^[6] ]
2. Elimination of traffic inducing incentives and introducing rewards for low-impact mobility [^[7] ]
3. Equitable and fair transport systems [^[8] ]
4. Multimodality and intermodality [^[9] ]
5. Demand Management instead of increasing infrastructure [^[10] ]

Many of these principles tackle problems caused by planning approaches that have prioritised individual motorised modes and roads. [^[11] ] Some of the problems arising from high vehicle ownership and use rates [see Table 1] have been successfully addressed by improved vehicle technologies, but “too many cars in a city will continue to be a problem no matter what fuel is used.” [^[12] ]

Abbildung in dieser Leseprobe nicht enthalten

Table 1: Problems in cities caused by road traffic [^[13] ]

In the following, the principles of sustainable transportation planning and policy will be linked to opportunities of improving urban characteristics – density, dimension, diversity – in Bangkok, a city with 7 million inhabitants in the ASEAN region.

3. Seizing the opportunities of density, dimension and diversity in Bangkok

Bangkok, the capital city of Thailand, is notoriously known for its high congestion levels. Yet, its urban structure – high density and high diversity settlements – renders the city centre perfect for minimizing automobile dependence. [^[14] ] A middle class bias of Bangkok transportation policy, however, has significantly increased the burdens of mobility.

3.1. Burdens of Mobility in Bangkok

The burdens of mobility in Bangkok can be divided as follows:

1. On a local level: congestion/overcrowding, air pollution, social mobility divide, constant noise pollution levels, land consumption and loss of agricultural lands and forests, high accident rates and related macro-economical costs, high macro-economical costs for road infrastructure provision and maintenance, especially in the new sprawling suburbs, and loss of street life and community
2. On a national level: high and increasing dependence on oil imports
3. On a global level: high emissions of CO2 accelerating climate change [^[15] ]

It is important to note that each burden affects the city in multiple ways, i.e. economically, socially, and environmentally, and that they are mostly interdependent. The three burdens with the biggest impact on urban development in Bangkok are currently 1) congestion/overcrowding, 2) air pollution, and 3) the social mobility divide and will now be described in detail. Data and insights were gathered from different sources. [^[16] ]

[...]

^[1] Vasconcellos, Banister 2005

^[2] Docherty 2008:83

^[3] Kraas 2007:12; Street 1997:140

^[4] Kraas 2007:9; Korff 2007:4-6; Lee 2007: 6, 16

^[5] Kennedy op. cit.

^[6] Newman 2007:71-72; Kenworthy 2003:62; Holz-Rau 2007:21; Gertz/Polzin 2009:777

^[7] Deakin 2001:6; OECD 2008:341; Böhler 2007:19; Banister 2005:76

^[8] Hine 2008:49; Zegras 2006:4; Tully 2007:38; Holz-Rau 2007:22

^[9] Tully 2007:38; Dennis/Urry 2009:94f

^[10] Newman 2007:74-75; Lyons/Urry 2006:3; Litman 2001; Victoria Transport Policy Institute TDM Database

^[11] Vasconcellos 1997:6

^[12] Lee 2007:72

^[13] Newman/Kenworthy 2007:80; Gudmundsson/Höjer 1996:279; Wolf 2007:343–347

^[14] Kenworthy 2003:62-62

^[15] Asian Development Bank 2006; Kraas 2007; Matsumoto 2005; Poboon 1997; Townsend 2003; World Bank 2000.

^[16] Currently, the most comprehensive data base for transport in cities is the Millennium Cities Data Base for Sustainable Transport compiled over 3 years by Kenworthy and Laube [2001] for the International Union of Public Transport. Another data collection referred to here is the pioneering work of the team around the Australian transport geographer Paul Barter [1999], containing transport data for 46 international cities. Both databases only contain data up to 1995. More recent data have been used as available, especially from the Thailand National Statistical Office and the CAI-Asia Initiative. A helpful collection of maps and figures was provided by the Atlas of Thailand [Kermel-Torrès/Lafitte 2004]. Additional data and insights have been gathered from field observations in Bangkok during a 1-week field trip of the author in March 2008.