Bribin underground river of Gunung Kidul regency is one of the rivers with major potential and is a source of water for the people of Gunungsewu, which is a karst area.
Moreover, the area is known as the area lacking water as the stream lies some 100 meter in the underground. Micro-hydro system in drilling and underground dam at the Bribin cave is expected to double water distribution. This project is expected to sustain water resource for a long time.
Up to this moment, karst mining by the surrounding communities have affected water supply. As a matter of fact, karst area is an area with abundant water content due to the cracks in the rocks that cause water to be absorbed deep in the rocks. Â
A research by UGM lecturer in Faculty of Geography, Tjahyo Nugroho Adji, S.Si., M.Sc.Tech., said that there is karst underground aggresivity difference to dissolve limestone between the upstream and downstream areas of Bribin River. â€œIn the dry season, the upstream showed that water can no longer dissolve limestone. On the contrary, underground water in the downstream can dissolve it,â€ said Nugroho Adji in open examination of doctoral promotion in the Faculty of Geography on Saturday (20/3).
In his dissertation, Nugroho explained the different aggresivity nature that is caused by the different cavity nature between upstream and downstream. The conduit enables polluters to enter Bribin at anytime. In terms of water resource supply, the Bribin cave hasÂ slow diffuse with small fluctuation. Meanwhile, other caves at Bribin underground generally have quicker diffuse so that in the summit of the dry season the debit is very low, particularly in the Gilap and Ngereng caves.
To journalists, Nugroho said that the use of karst for limestone needs to beÂ reevaluated for water sustainability. â€œTherefore, conservation is required for the rainwater catchment surface area of Bribin underground,â€ said the man born in Magelang, 28 January 1972, who earned cumlaude distinction in the examination.