Paper Title
The Combination Of Hollow Precast Block And Vegetation To Reduce Runoff On Slopes

Abstract
Rain fall is an important factor in runoff rate especially if the land is not covered by vegetation, all this time various methods to reduce runoff have been used but the existing method has not been able to answer all problems and tend not to pay attention to the effect on the environment, along the development of the concept of river- and slope restoration, becomes a demand for slope protection for the characteristic of ecological to be maintained. Various types of cliff protective have advantages and disadvantages both pure vegetation or pure structures, hence we evaluate and design the model of cliff protective of both methods, i.e by designing hollow precast block and varying with grass vegetation to obtain the benefits of both methods.The research aimed to determine the amount of runoff discharge that occurs on land cover variation with Hollow Precast Block and Grass Vegetation on the slope of ground level 15°, 25° and 40°.Sampling is started with rainfall calibration so that it can get 3 (three) types of rainfall, then make scale model with soil slope 15°, 25° and 40° on rain fall simulator tub, then variation of land cover model including also a model of Hollow Precast Block is arranged on slope model and performed running with 3 (three) variant of rainfall, 4 (four) variants of land cover model, and 3 (three) variants of slope, the three variants of rainfall, total average runoff indicates land cover using Hollow Precast Block with a combination of grass vegetation can significantly reduces runoff by 41.06%, 45.41% and 41.77% of 15°, 25° and 40°, respectively of land without cover, also steeper the slope of land then amount of runoff is also getting higher. Keywords - Runoff, slope, Hollow Precast Blocks, vegetation, rain fall simulator