Abstract. Water is one of the important components that support human life. With an increase of population, there is also an increase in water consumption. In addition, improved living standards and industrial activities require improved water quality standards. However, the increase in demand is in contrast to the availability of existing water sources, and the surface water of existing rivers is strongly influenced by the tides. The flavor of surface water during the dry season is sometimes very salty. Water is not only salty but also has higher turbidity than the standard water quality. The use of rainwater as a second alternative is very limited, which could only be acquired in rainy season. To overcome chronic problems, such as lack of clean water supply, one requires appropriate water treatment technology. An appropriate water treatment system is a combination of conventional and advanced technology. Desalination, such as household scale Reverse Osmosis (RO) membrane technology has been developed to address the problem of raw and clean water availability. RO membrane technology is a water treatment by molecular filtration using a primary membrane such as reverse osmosis pressure, and one of the materials that can be utilized for the upside osmosis the coconut trunk. Coconut trunk has a fiber that serves as a filter whose mechanism of action is very similar to reverse osmosis. Therefore it can be said that coconut trunks can be used as an alternative to water treatment by reverse osmosis membrane method to obtaian clean raw water. The water quality of the filtration product with the coconut rod is temperature, the degree of acidity, dissolved oxygen, and dissolved soil which are still within the standard range of clean water. However, the electrical conductivity is still below the maximum limit of the standard water class for agriculture. Filtration with vertical fibers can reduce turbidity by 157.1 NTU. However, it is not effective to use these coconut filters for river with low-turbidity. Only the water in Barito River and Kemuning Banjarbaru meet the class of clean water class A of 5 NTU, two other rivers have decreased turbidity after going through filtration process, but the value is still > 5 NTU.