Clean water plays an essential role in all living things. However, the availability of clean water in Indonesia is insufficient to fulfill the total need for clean water, especially during the dry season. One of the alternative sources of clean water is rainwater. This study aims to understand the characteristics of rainwater in Indonesia as well as the effect of the variations of type, arrangement, and thickness of the simple filter media on the rainwater in Indonesia. A literature study from several studies is conducted regarding the use of rainwater as clean water with filters made from simple media to improve clean water by utilizing gravity filtration technology. The key descriptors used in this review include “rainwater filtration”, “filtration”, “rainwater harvesting” and “media filtration”. The quality standard used in this study is based on the Ministry of Health Regulation No.416/Menkes/Per/IV/1990. Based on the literature, simple filtration technology can significantly reduce some parameters value where the value of efficiency is more than 50% for parameter turbidity, TDS, Pb, arsenic, total coliform, hardness and nitrate. However, it has not been able to reduce the parameter of sulfate, nitrite, chloride, magnesium significantly. The review shows that the filter medium that is effective and easily accessible are gravel, zeolite, activated carbon, sand, cotton, sponges with a total media thickness of 20 cm, 70 cm, 80 cm, 100 cm, and 105 cm and the time required to perform the filtration is about 10-15 minutes.

Jakarta is one of area that often experiences in flooding. Jakarta is increasingly vulnerable being affected due to the limited catchment area. Massive development with water tight surface conditions and limited water absorption caused by about 85% of rainfall falls in the Jakarta area. As a result of lack absorption in Jakarta, the amount of rain falling and flowing into the sea and rivers will increase. When the capacity of the river does not cover the river water automatically overflows it will cause flooding. Mitra PKM is a junior high school building located in the Menteng area, Central Jakarta. In recent years the Mitra Area has overcome flooding disasters, the teaching and learning process in the Mitra region has being obstructed. The clean water crisis also occurs in the Mitra area, this is due to the location of the Mitra which is quite connected to office buildings that have a large enough need of clean water. The average rainfall in Indonesia is 2779 mm per year, in Jakarta around 2500 mm per year, with a total of 180 rainy days/year. According to average rainfall, is the potentially of water resources and it can be utilized optimally. Sources for water specifically rainwater resources by making infiltration wells. Infiltration wells work to collect surface water and then absorb the soil to become ground water reserves. Converting sufficient (surplus) ground water, will compensate for drought in the dry season in the form of water flow.

This study aims to obtain the optimalization of rainwater harvesting through different technologies, for future groundwater conservation to be used in dry season. This study could demand of human consumption and their activities. The analysis of stormwater run-off volume is used for capacity and quantity of infiltration well. It refers to Standard Depth Calculation from PU (Pekerjaan Umum) of infiltration well. Based on the research results, the infiltration well using porous walls material (permeable wall) with the dimension 1.5x1.5m, permeability coefficient 0,015184 m/hour, rain intensity 0,0115 m/hour, rain duration 60 minutes, the depth of well is 0,889 m. The volume of stormwater in one week with assumming two times rainy days is 4.232 liters. The infiltration well built in the study area was a well with a 2 (two) meters, so that the recharge well discharge obtained 0,216 m3/hour. The excess of stormwater was put into infiltration well is 3,192 liters. If the excess water from rainwater harvesting is accommodated into infiltration wells, must be provided 15 wells with 2 meters depth. If the infiltration couldnot accommodated the excess water, it will flow to city drainage canals. The results of this study are to estimate the potential stormwater volume, the conveyance system and the groundwater conservation system.