Sediment analysis and assessment of water quality in spacial variation using water quality index (NSFWQI) in Moragoda canal in Galle, Sri Lanka

Abstract

The Moragoda Canal in Galle, Sri Lanka is one of the most widely used canals for water supply for various purposes. Water quality is deteriorating due to industrialization, agricultural practices and sewage disposal. Therefore, this study aims to examine the effects of industrialization and human activities on water quality and sediment composition in the Moragoda Canal in terms of water quality indices based on the National Sanitation Foundation Water Quality Index (NSF-WQI). Sampling was done in three different stretches of the streams such as upstream, middle stream, and downstream for evaluation of water quality and sediment composition analysis. Nine water quality parameters such as dissolved oxygen, chemical oxygen demand, biological oxygen demand, temperature, pH, turbidity, phosphate, nitrate, and total coliform were considered for index estimation. The correlation between water quality parameters generated by principal component analysis shows that the main parameters affecting the water quality are vary in three different stretches of the canal. Based on the water quality indicators, anthropogenic activities are accountable to deteriorate the quality of the canal. Therefore, the pollution status of the canal need to be aware publicly.

Keywords

• Moragoda canal
• Sediment composition
• Water quality index
• Principal component analysis