Water quality analysis of bribin underground river as the source of raw water for a government-owned water company (pdam) in the bribin management unit, Gunungkidul regency-Indonesia

Bribin Underground River supplies raw water for a government-owned water company, PDAM, and has more potential than the other three of its sources, namely Baron, Seropan, and Ngobaran. In addition to sufficient quantity, raw water has to meet a set of water quality standards. This research was intended to describe the quality of raw water from the source to the service areas spatially. The water quality was measured directly in the field and then in the laboratory using the water samples collected by the purposive sampling technique. The test analyzed physical, biological, and chemical parameters. According to Governor Regulation No. 20 of 2008, some water quality parameters of Bribin Underground River exceed the standards for Class I raw water i.e. TSS, pH and NO3. Besides, according to the Decree of Health Minister No 492/MENKES/PER/IV/2010, pH and total coliform number exceed the standard. A spatial variation in water quality was detected from Bribin Underground River to customer taps, especially in parameters that have significant changes, such as pH, EC, TDS, TSS, nitrate, and total coliform. Spatially, the content of TDS and EC that correlates each other show a fluctuating result according to water flow treatment in water treatment plant (WTP) and the reservoir. pH and total coliform show increasing trends of number from the source to customer taps, whereas TSS and nitrate show decline trends. © Published under licence by IOP Publishing Ltd.