Was Medieval Sawankhalok like Modern Bangkok, Flooded Every Few Years but an Economic Powerhouse Nonetheless?

Abstract

"Sawankhalok" is the name of the medieval city that was part of the Sukhothai kingdom and was located on the banks of the Yom River about 50 km north of Sukhothai. This city shows evidence of flood sedimentation of up to 2 m since its founding, prompting the question of when the flooding occurred and why the city was founded in an evidently flood-prone site. Several elements of the physical environment, especially the disposition of hills and river, are propitious in terms of Thai cosmology and almost certainly constitute one element in the decision to locate the old city at the site. Flood damage to the walls of the city indicate, however, that the city's founding and early growth probably occurred during a period of lower flooding. This conclusion is consistent with the long Chinese records of regional meteorological phenomena that are related to the strength of the monsoon, one of the key controllers of river flow at the old city. After being founded, the city persisted at this location despite a return to a regime of higher and, possibly, more frequent floods. This persistence was almost certainly related, at least in part, to the economic and political power that resided in the city and was founded on flourishing ceramics and agricultural industries and the decline of Sukhothai itself. The history of old Sawankhalok shows that the physical environment remains an important element in understanding the emergence of proto urban sites, despite the lack of attention paid to this currently unfashionable element of urban development. It seems that the old city would have been hard-pressed to develop had it been subject to inundation and sedimentation by floods. The modern Asian supercities are evidently likewise resilient to the extremes of the physical environment. Inertia is a strong factor in this resilience, but one might suggest that Bangkok would also find it very difficult to cope with regular inundation by flood waters and sediment. KEYWORDS: geoarchaeology, historical climatology, urbanism, Thailand, Southeast Asian archaeology.