Modeling sediment export potential of the Rio Caonillas watershed (Puerto Rico)

The Hydrological Simulation Program---FORTRAN (HSPF) in interface with Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) v.3.0 was used to study soil erosion and sediment export of Rio Caonillas watershed, Jayuya, Puerto Rico. Six years (1995--2001) of continuous meteorological, flow and suspended sediments data were used to calibration and validation the model. When applied to the Caonillas watershed, HSPF simulation results of monthly streamflow and suspended sediment load during the five year simulation period were fair (R2 = 0.72, R2 = 0.73, respectively) without extreme events generated by Hortensia and Georges hurricanes. Nash-Sutcliffe coefficient and coefficient of determination (R 2) were highly sensitive to extreme events values such as the precipitation events related to Hortensia and Georges hurricanes. Agricultural and barren (sand mines and domestic landfill) areas yielded the highest soil losses, contributing 54% and 23% of annual soil erosion during the simulation period, respectively.