ANALYSIS OF WATER QUALITY FROM BIO-PHYSICAL-CHEMICAL FACTORS OF THE ASAHAN RIVER NORTH SUMATRA

Asahan River is one of the rivers that pass in North Sumatra Regency with a length of 147 km which empties into the Malacca Strait. The Asahan River is classified as a class I (one) river. The conversion of land functions is quite large around the Asahan watershed, for the stone mining sector, the oil and gas sector, the industrial sector, plantations and agriculture. This number of activities causes the Asahan river to have a large potential to experience a decline in quality. Field observations indicate that several activities have the potential to introduce pollutants into the Asahan River which may dispose of production waste directly or run off production waste into the river. The purpose of this study was to analyze the quality of the Asahan River by determining the Water Quality Status of the Asahan River. The research area was carried out on the Asahan River as far as 45 Km. River water quality was measured and observed at 3 sampling points for physical, chemical and biological parameters. Quality analysis and determination of water quality status used the Storet method and the pollution index method. The results are (1) DO, BOD, COD, Fecal coliform and Total Coliform parameters have exceeded the Class I river water quality standard according to South Kalimantan Governor Regulation No. 5 of 2007 which states that the water quality of the Asahan river has decreased (2) There has been a shift in the status of the water quality of the Asahan river from upstream to downstream which is indicated by the Storet value and the pollution index value (IP) which tends to increase based on river criteria according to Government Regulation number 82 of 2001. However, these waters can still be inhabited by various animals including Gastropods, Fish, Paramecium, Plankton and other microorganisms.