A Review of HSPF Evaluations on the Southern United States and Puerto Rico

Diaz-Ramirez, J., McAnally, W. H., & Martin, J. L. (2010). A Review of HSPF Evaluations on the Southern United States and Puerto Rico. 21st Century Watershed Technology: Improving Water Quality and the Environment. Costa Rica.

The objective of this study was to evaluate the Hydrological Simulation Program – FORTRAN (HSPF) in three different environments: an upland basin in Alabama and Mississippi, a humid, subtropical watershed in coastal Alabama, and a steep-slope tropical catchment in Puerto Rico. The HSPF model was coded to simulate hydrology, hydraulics, water quality, nutrients, soil erosion, and sediment transport in rural and urban environments. This project used the HSPF version linked to the EPA Better Assessment Science Integrating Point & Non-point Sources (BASINS) model. The HSPF model was applied to the 1,852 km2 Luxapallila Creek basin, 140.1 km2 Fish River watershed, and 98 km2 Rio Caonillas catchment. The HSPF model was successfully adapted to model daily hydrological processes in each study area. When analyzing flow duration curves showed that baseflow was more significant in the Fish River watershed than the other two drainage areas because flow values between 10% and 100% of the time had a low slope. The calibrated models explained more that 71% of the daily variability of streamflows. The models performed better during calibration than the verification period. Coefficient of determination and Nash-Sutcliffe statistics were good on a daily and monthly periods. The three models were evaluated under a large range of streamflows (0.4 m3/s to 897 m3/s). In general, this study showed the robustness of the HSPF model inextreme environments (small catchments vs. large basins, flat vs. hilly areas, tropical vs. subtropical climates).