Water quality spatial and temporal evaluation and auto-purification simulation from the Sao Simao stream watershed, SP

• Published in: Revista ambiente & água Vol. 7; no. 3; p. 141
• Main Authors: Goncalves, Julio Cesar de Souza Inacio, de Souza Sardinha, Diego, de Souza, Antonio Donizetti Goncalves, Dibiazi, Andre Luis Bigaram, Godoy, Leticia Hirata, da Conceicao, Fabiano Tomazini
• Format: Journal Article
• Language: English
• Published: Instituto de Pesquisas Ambientais em Bacias Hidrográficas (IPABHi) 01.12.2012
• Subjects: auto-purification mathematical modeling; Freshwater; waste water; Water quality evaluation
• ISSN: 1980-993X; 1980-993X
• DOI: 10.4136/ambi-agua.894

This study evaluated the water of Sao Simao stream watershed. For this, six sampling points were established and twelve samples of water were collected during the months of March, May, June, July, August, September, October, November, and December of 2005 and January, February, and March of 2006. The following variables were analyzed: discharge, temperature, turbidity, pH, electrical conductivity (EC), dissolved oxygen (DO), alkalinity, chloride and TSS (total suspended solids). The Streter & Phelps model which correlates the variation of the deficit oxygen with the distance was applied to evaluate the Sao Simao stream auto-purification. The characteristics of the Sao Simao stream near its spring until it reaches Sao Simao city allowed concluding that there is low interference in its quality. However, the absence of treatment of domestic wastewater at Sao Simao city reduced the water quality and increased the degradation process of Sao Simao stream after passing through the city. The Streeter & Phelps model allowed identifying the auto-purification zones in this stream and indicated the need for primary wastewater treatment, with an efficiency of 30%.