Metode Gridding Untuk Teknik Evaluasi Sedimentasi Waduk(Evaluation Technique of Reservoir Sedimentation as Revealed by Gridding Method).

The determination of reservoir life time is often based on the prediction of reservoir sedimentation to meet its dead storage capacity. The complexity of the reservoir sedimentation process is highly influenced by geometry of the sediment conveyance system. The sediment conveyance system may be distinguished into two main systems, i.e., land system and stream system. The migration process of the material from land system presents in the form of sheet erosion, which in turns enter the stream system. The migration process of such material in the stream is a function of stream geometry, particularly the river crossection, the flow characteristics, and interaction between wet perimeter and the flow of water. The above mentioned background shows the necessity of the development of both monitoring and evaluation techniques to study the rate of reservoir sedimentation. This paper deals with the development of technique to evaluate the result of monitoring activity by means of gridding method. Development of method by gridding the random information obtained from random reservoir bed measurement is performed. Application of such method is carried out to study the sedimentation of Sermo Dam. The sensitivity of the method is analyzed, and the application of the technique which is performed in the form of simple computer software is presented. The gridding method as assembled through KARAKTER-01 has the following advantages, i.e., a). simple field meausurement, b). easy and accurate analysis of total sedimentation, and c). exact identification of sedimentation position. Based on the spillway crest evaluation, the conventional reservoir sedimentation evaluation technique said that the annual sedimentation rate is 95731 m3. This conventional technique did not perform the position of the sedimentation over the reservoir bed. The application of gridding method shows the that the annual rate of sediment entering the reservoir is 310000 m3. distribution of the sedimentation position over the reservoir bed is one among many practicalities performed by KARAKTER-01