Application of the HEC-HMS model for runoff simulation in a tropical catchment

摘要: Hydrologic simulation employing computer models has advanced rapidly and computerized have become essential tools for understanding human influences on river flows designing ecologically sustainable water management approaches. The HEC-HMS is a reliable model developed by the US Army Corps of Engineers that could be used many hydrological simulations. This not calibrated validated Sri Lankan watersheds need data inputs to check suitability study location purpose. Therefore, this employed three different approaches calibrate validate 3.4 Attanagalu Oya (River) catchment generate long term flow tributaries.Twenty year daily rainfall from five rain gauging stations scattered within monthly evaporation same years agro meteorological station Henarathgoda together with at Dunamale 2005 2010 were in study. GIS layers needed as input prepared using Arc 9.2 calibration sub 2007. was adjusting methods. parameters changed performed separately selected methods, Soil Conservation Service Curve Number loss method, deficit constant method (the Snyder unit hydrograph Clark method) order determine most suitable catchment. new set (2008-2010). simulated each methods tested statistically coefficient performance, relative error residual method. simulates more reliably than As SCS does perform well. can simulate ungauged tropical watersheds.Snyder method.As well.Deficit