The previous works on the subject of urban sprawl showed that urban sprawl is a
complex phenomenon but they have not identified a clear definition of what exactly
urban sprawl really is. Assessing urban sprawl is even a more difficult task even
though there are numerous attempts that have been made to assess urban sprawl.
Different scientific methods and approaches were used for this task. Some researchers
have attempted to assess urban sprawl in a simple manner while some attempted multi
dimensional approaches such as multi factor approach, integrated urban sprawl
approach, geo-spatial approach etc.
The problem is that these assessment methods are not appropriate in the Sri Lankan
context, because most of them address urban sprawl as experienced in the Western
world. Therefore, this research attempted to fill this gap by identifying a suitable
method for assessing urban sprawl in Sri Lanka.
It is noteworthy that, this is the first attempt for assessing urban sprawl in Sri Lankan
context as surveys of previous studies indicate. Generally speaking urban sprawl in
Sri Lanka is on the increase. But it has not yet been empirically assessed or calculated
in detail. Major cause that influenced urban sprawl in Sri Lanka was the rapid urban
expansion. It may be that this might have been encouraged by not having a proper
definition of "urban" applicable to the country.
Under these circumstances and the present phase of development, the research
identified a multi-factor approach to assess urban sprawl in Sri Lanka. For this
purpose 12 indicators have been selected which have been associated with urban
sprawl, viz. urban built up density, residential population density, leapfrog
development, strip highway development, loss of arable land, encroachment of open
space, damage s to eco sensitive areas, segregated land use, proximity to urban
functions, availability of local area development plans, land values and road density.
Combining all these indicators in a rational weighted manner the research formed an
Integrated Urban Sprawl Index (IUSI) for assessing urban sprawl in Sri Lanka.
Land use changes which have been taken place in between 1992 and 2002,
highlighted the gradual increase of urban expansion of the selected area. For instance,
by 2002, some rubber plantation areas are completely converted into residential
purposes. Further, it is found that the low land values of these areas are directly
influenced for land conversion.
The validity of the formulated IUSI was tested in ground situation of 2002 in the city
of Kalutara and its suburbs. For this purpose, GIS techniques such as mapping,
modeling and overlaying; photo interpretation, spread sheets, Graphs and word
processing were applied to analysis urban sprawl in Sri Lanka.
VII
Finally, the urban sprawl assessment in Sri Lanka carried out in two ways; (1) Urban
sprawl assessing by individual component and (2) urban sprawl assessing by IUSI.
The results of individual component analysis illustrated four clusters of urban sprawl
that can be identified in the area such as highly compact, compact, sprawling and
highly sprawling while the integrated urban sprawl index revealed only three types of
development patterns such as highly compacted, compacted and sprawling areas.
