The research aimed to study the effect of groin application to erosion at the shoreline. The method utilized the bathymetry and topography data of north beach of Balongan, West Java. Modeling of the shoreline change due to groin installment used software called GENESIS. Based on analysis result, it is found that the significant wave direction comes from the southeast with significant wave height of 1,18 meters and surf zone width of 140 meters. It is concluded that at research area of north beach of west Java, I-groin with length of 70 meters and T head groin of 60 meters in long T-groin effectively overcome erosion and advance the coastline by 10786,62 m2 or in average 6,3 meters.

To improve the moisture susceptibility of concrete structure that will be exposed to water, an admixture should be added. One of the additives that can be added is Xypex C-1000 NF, which a crystalline material. A number of past studies have shown that this additive is effective in improving the moisture resistance of concrete structure. However, the application of this additive in Indonesia was found to be challenging as the performance of the concrete mixture was not as good as expected. This research aims to evaluate the effect of adding various percentages of this additive, various amount of water to be added to the concrete mixture, and the methods of mixing the materials, which are wet and dry methods, by looking at both the slump value and the compressive strength of the concrete specimens. From the research results, it was found that the methods used to mix the additive matter to produce a desirable concrete quality. The wet mix method is the preferable method as it produces less variations in compressive strength test results regardless of the additional water amount. It was also found that, by using both dry and wet mix methods, the usage of Xypex C-1000 NF can improve the compressive strength value.

Abstract.The Indonesian Regulation which refers to the ICOLD Regulation (International Committee on Large Dam required have the Emergency Action Plan (EAP) guidelines because of the dams have potential failure. In EAP guidelines there is a management of evacuation where the determination of the inundation map based on flood modeling. The purpose of the EAP is to minimize the risk of loss of life and property in downstream which caused by dam failure. This paper will describe about develop flood modeling and inundation map in Krisak dam using numerical methods through dam break analysis (DBA) using hydraulic model Zhong Xing HY-21. The approaches of dam failure simulation are overtopping and piping. Overtopping simulation based on quadrangular, triangular and trapezium fracture. Piping simulation based on cracks of orifice. Using results of DBA, hazard classification of Krisak dam is very high. The nearest village affected dam failure is Singodutan village (distance is 1.45 kilometer from dam) with inundation depth is 1.85 meter. This result can be used by stakeholders such as emergency responders and the community at risk in formulating evacuation procedure.

In Purwakarta Regency there is a new area designated as a residential, commercial and industrial area, namely the Jatiluhur Estate Area. With the new area, it is necessary to know whether the availability of water can meet its water needs (water reliability) for the next 50 years. This research also carried out the water reliability mapping. Based on the analysis, both water availability with dependable discharge Q80% and Q90% overall and monthly, can fulfil the water needs of Jatiluhur Estate until 2070. However, with the regulation of water intake in the river, a ground tank is needed which takes into account the water loss of 19%, so that Q90% dependable discharge can fulfil the need while carrying out the regulation. From the results of monthly water reliability mapping, water reliability with Q80% and Q90% (overall) generate one color, four colors with Q80% (monthly), and three colors with Q90% (monthly). Whilst, the annual water reliability map generates one color for water reliability with Q80% and Q90% both overall and monthly.

This paper is a review of the development of simulation model for water-energy nexus in achieving sustainable water management in Indonesia. It is important to understand complex interconnection of water and energy to create strategy since Indonesia is facing the decrease of resources and increase of demand. A system dynamic simulation model is a reliable tool to simulate the relationship between water and energy. This study objective is to develop a conceptual model that can determine the amount of demand, supply, or import of water and energy. The method used is a Vensim (Ventana Simulation Environment) program. This conceptual water-energy nexus framework could further being tested to calculate the balance of water and energy element and creating sustainable resource management plans.