REDE DE DRENAGEM URBANA EM ÁREA TROPICAL: MUDANÇAS NA MORFOLOGIA DO CANAL E NÍVEIS DE POLUIÇÃO DAS ÁGUAS – RIO DOS MACACOS – RIO DE JANEIRO – RJ

Abstract

The present work, accomplished in the urban area of the city of Rio de Janeiro, aimed to analyze the variation occurred in the morphology of Macacos river channel. The levels of pollution in the waters along the longitudinal profile was also evaluated due to human actuation. The area was monitored from March 2002 until February 2003. The changes in the morphology were identified through the relation among variables obteined in field, as width, depth, cross-sectional area, hydraulic ray and relation width/depth (W/D). In order to evaluate the levels of pollution in the waters of the channel some interpretation of the obtained values from parameters pH, DO, BOD and colimetry were performed. In the studied period, the largest variation in the morphology were identified in the cross-sections area where occurred the erosion of the channel (which increased the channel capacity to 0,28m2 in PT1) and high deposition identified through the reduction of the channel to 0,90m2 in PT5. Regarding to the level of water pollution, extremely high rates of fecal coliform were identified (1.600.00 NMP/100 ml for all the points), whereas reduced values of DO and BOD were identified next to downstream, due to the largest effluent concentration.