MAXIMUM FLOW STUDY BY THE HYDROGRAM METHOD FOR A WATERSHED IN THE SOUTH OF SANTA CATARINA, BRAZIL

Knowing the maximum flow and its return period is extremely important for safely dimension hydraulic projects flood prediction control also water erosion prediction. Thus, this study aimed to evaluate Capivari river watershed flow, located in south of Santa Catarina, that has a flooding history. The method used was United States Soil Conservation Service (SCS) Triangular Unit Hydrogram (current Natural Resources Service), and, effective rainfall, US Curve Number (SCS-CN) used. To estimate watershed, three background moisture scenarios (CNI, CNII CNIII) six empirical equations proposed rural watersheds were adopted calculate concentration time. observed upstream 34-years historical series used, measured at São Martinho downstream fluviometric station (code 84598002), outlet section watershed. results showed flows estimated by SCS-CN conditions CNIII had greater differences (-198% -287%) compared flow. smallest verified CNI condition all analyzed periods (2, 5, 10, 15, 20, 25, 50 100). Also, it that, longer period, smaller difference among flows, 50-year indicating most appropriate studies extreme events