%0 Journal Article %T Estimativa de ¨˘rea impermeabilizada diretamente conectada e sua utiliza£ż£żo como coeficiente de escoamento superficial %A Garotti %A Leonardo Monteiro %A Barbassa %A Ademir Paceli %J Engenharia Sanitaria e Ambiental %D 2010 %I Brazilian Association of Sanitary and Environmental Engineering %R 10.1590/S1413-41522010000100003 %X this paper presents a study of characterization of land occupation and its use in the city of ribeir£żo preto (s£żo paulo), as well as a detailed analysis of the urban imperviousness and hydraulic connectivity of the plots. the runoff coefficient (c) for siz sub-basins was evaluated on the basis of three different definitions. the peaks of outflow for the sub-basins were calculated using the rational method with the estimated values of c. it was identified that the imperviousness increases as the area of the plot decreases. the estimative of the c show important differences in its values, influencing the outflow. the use of tables with detailed and maximal c values beyond its superior limitation is equivalent to the values estimated with cdcia. it is recommended that the cdcia relative to the area be estimated based on the plot or field researches. %K runoff coefficient %K urban draining %K directly connected impervious areas. %U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1413-41522010000100003&lng=en&nrm=iso&tlng=en