PENELITIAN KUALITAS AIR BENGAWAN SOLO PADA SAAT MUSIM KEMARAU

Abstract

The Bengawan Solo which flows through Central and East Java is the largest river in Java Island, and its
water is used for various activities such as agriculture, fishery, domestic use, irrigation, and water
resources for drinking water. Based on a research carried out in upstream Bengawan Solo, water quality
shows a decline indicated by the decrease of dissolved oxygen and increase of BOD and COD. At location
Grogol, dissolved oxygen ranges between 4.4 7.9 mg/L and decreases at Kemiri to 0 6.4 mg/L. BOD at
Grogol shows a range between 1.3 4.5 mg/L increasing to 4.8 8.1 mg/L at Kemiri. COD range between
3.7-13 mg/L at Grogol increases to 12 30 mg/L at Kemiri. In downstream Bengawan Solo, at location
Napel and Babat, water quality indicates an increase indicated by increase of dissolved oxygen, and
decrease ofBODand COD. The increasing dissolved oxygen and decreasingBODandCODin downstream
area shows that the self purification process is happening in the river. The Fecal coli form bacteria at each
location is found very high and beyond criteria.