Environmental impacts in the vicinity of Rawan Oya in Pathadumabara Division

Abstract

Water resource is essential for all forms of life. Pollution of the river water is one of the main problems associate with water resources in Sri Lanka. The Rawan Oya (RO) is known as a polluted river which origins from the Hunnasgiriya mountain range and drains to Mahaweli River close to the Polgolla Uyanwaththa. The main objective of this study was to examine the main causes and impacts of the RO and its environs. Questionnaire survey, focus group interviews and observations were applied to collect data and information. Ten Grama Niladhari divisions were selected from Pathdumbara division to achieve the objectives. Households were selected randomly. The observation revealed that the water is polluted considerably in this river especially close to the city centre of Waththegama. The dumping of the urban solid and liquid waste was identified as the main reason for pollution of river. Deposited fertilizers were observed in some places near to the paddy fields. Since householders use some places as bathing places, various nitrate and phosphate composites were accumulated in the river. Bank erosion and sedimentation were also identified in RO. According to the perception of the respondents, the flora and fauna population have been decreased in RO ecosystem. Due to the high rate of bank erosion and deposits of sedimentation, the depth and the water storage capacity have been decreased significantly. Although some actions have been taken for the conservation of RO, those are not functioning well due to the lack of awareness of the community and inadequate attention of the responsible authorities. Community water management practices should be introduced to preserve the water in this river. Municipal council of the Wattegama can implement waste collection system at least to the center of the city. Soil erosion preventive methods and proper land use practices should be introduced to the residents who stay close to the Rawan Oya.