Two series of suspended sediment concentration measurement within a stream network carried out during the dry and rainy season are presented in this paper. Information on suspended sediment concentration obtained from measurement are plotted on the map of stream network to allow a comparison between designated rivers.. The finding suggests that concentration of suspended sediment do not coincide with stream order. First stream order of both series of measurement have a lower concentration level of suspended sediment than that of the second and the third order respectively. A noticeable difference experienced by the fourth order river. Quite unexpectedly it has a lower suspended sediment concentration than the second and the third order rivers within the stream network. These features are found both in dry and rainy season measurement. Although there is a complexity in suspended sediment concentration transported by rivers of different order, the resulting map is very useful to be adopted as a main consideration in determining suitable approach and priority works in dealing with potential erosion and sedimentation of high degrading basin both using engineering and non engineering approaches.

Sedimentation is an important issue in reservoir rehabilitation and maintenance. This problem is worsened by seasonal water scarcity as a characteristic of arid catchments. Worldwide loss of storage capacity due to sedimentation is much higher than the increase of capacity by the construction of new reservoirs. Further, sedimentation hinders the safe operation of not only shallow reservoirs but also deep reservoirs by means of turbidity currents which sporadically transport large volumes of sediments down to the dams. This study analyses the real case of Pengga reservoir and Batujai reservoir located in Central Indonesia. Selected sediment management alternatives were analysed and evaluated based on technical, social and environmental criteria. Evaluation of sediment management alternatives was conducted by utilising the REServoir CONservation (RESCON) tool. Results showed that, first, both flushing techniques and hydrosuction are feasible whereas dredging and trucking are not. Secondly, the flushing technique outweighs the Hydrosuction Sediment Removal (HSRS) method. Thirdly, application of the HSRS method in both reservoirs shares one thing in common, i.e. it requires an appropriate combination of the number of suction pipes as well as minimum suction pipe diameters. Lastly, there are some differences in the details of implementation of the flushing technique to both reservoirs.

Currently, there are many efficient and effective sprinkler irrigation tools on the market, so it is necessary to be careful in choosing for irrigation. Among them, the Meganet 24D Netafim, including the type of irrigation tool, which still needs testing to know its performance. This study aims to examine the sprinkler irrigation performance of Meganet 24D Netafim, on variations in flow rate and distance between sprinklers, related to irrigation uniformity (CU) and irrigation radius (Rn). This test was carried out on an area of about 1 acre, at a flow rate of Q1=0.42/sec, Q2=0.51 l/sec, Q3=0.52/sec, Q4=0.56 and the test sprinkler distance, r1=2 ,5m, r2=3m,r3 = 3.5m and r4 = 4m. The results of data analysis are presented in the form of tables and graphs and concluded descriptively. The results showed that, in all variations of Q and sprinkler spacing r1, r2, r3 obtained irrigation uniformity (CU) above 85% which was classified as high, while in the r4, Q1 and Q2 tests, CU was obtained below 85% which was considered low. All discharge variations, showing irrigation radius (R) about 5 m. So at r4 sprinkler spacing, it is not recommended in irrigation applications.

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