SWAT modeling -- an integrated approach for the identification of
critical diffuse pollution sources in the Kolleru Lake catchment, India
Abstract
Freshwater ecosystems are facing severe threats by human activities. As
a consequence of this, they can get disturbed. In developing countries,
like India, freshwater lakes are endangered primarily by agricultural
activities, which often accelerate erosion and the runoff. The massive
application of pesticides and chemical fertilizers to agricultural lands
is one reason for eutrophication in the Kolleru Lake. Industrial
pollution causes deteriorating water quality and makes them unfit for
drinking water to the inhabitants of the villages around the Kolleru
Lake. Besides, the indiscriminate rise of fishponds across the lake is
another source of pollution to the lake. The different natural and
anthropogenic influences increase the highly complex ecosystem of the
lake. Managing these ecosystems is a challenging task. Due to the lack
of an integrated approach and comprehensive environmental policy,
Kolleru Lake has been becoming an ecological crisis area. Diffuse
pollution sources are still remaining. Together with inadequate
management planning and actions, they are contributing to the
deterioration of the water body of the Kolleru Lake. Therefore, the
objectives of this study are to ascertain the priority control areas
aiming at socio-economic development for the long turn protection of the
lake water quality by applying the Best Management Practices (BMPs). For
this purpose, the Soil and Water Assessment Tool (SWAT) was used to
identify the critical areas of the lake’s catchment in terms of
pollution from agricultural runoff into the tributaries of the Kolleru
Lake and the lake itself. Further, suggestions were provided for the
implementation of agricultural management practices to minimize
pollution levels.