CONCLUSION

Fig. 6. The First Greater Bangkok Land-use Plan 1933 (source: author)

Fig. 7. The Bangkok Land-use Plan 2013 (source: Foto_momo) There seems emphasizing the failure from top-down American urban models that major highways and roads dominate originally the pattern of Bangkok land-use development. Guerra (2004) claimed that Bangkok land-use plan unexpectedly originates its mistake, the lack of secondary infrastructure becomes the problem of urban growth, the inadequacy of access to distribute roads and the insufficiency of piped water and sewage systems generate obstacles to produce more efficient development patterns. The land usage of Bangkok presents two separated characteristics. The outstanding of mixed land use is the first characteristic. Residential zone, commercial zone and mixedscale industrial zone seem to be increased only in a single district without efficient control on their land use. Drainage and waste management systems, which are the basic facilities, are not usually built without problems (Krongkaew, 1996). The lack of efficient roads in the majority of Bangkok's extended area is the second characteristic, streets were built by private contractors for their real estate projects because the government could not provide sufficient roads which emphasizes the remaining problem that many systematic and interconnected networks was not built efficiently (Ross et al., 2000; Webster 2000) (Fig. 8 and Fig. 9). These private streets, which were not built accordingly to the public road layout, caused critical traffic problems to public road network in many areas where can be defined as poor accessibility. Moreover, this ineffective road network causes severe traffic congestion concurrently increasing air pollution which damages the health of urban dwellers. The rapid growth of suburban areas also confronts the problem of inadequate water supply, as the increasing demand could not be fed by the limited supply. Suburban citizens are forced to consume underground water exacerbating land subsidence, which causes critical flooding in raining season (Krongkaew, 1996; Webster, 2004). So, it seems that Bangkok social and physical problems are led consequently by inappropriate topdown American urban patterns.