Determination of pH-BOD-COD and degradation in batang arau watersheds at Padang city

This research aims to determine the pH, BOD and COD in river basin region and its relation to the occurrence of damage to the environment. The study was conducted by sampling at six locations representing the upstream region, the central region and the region downstream/estuary for four years, from 2011 until 2014. The sampling locations in the watershed Batang Arau at Padang city, include Lubuk Paraku (section 1), Banyan Lubuk Kilangan (section 2), the center, Bridges Lubeg by pass (section 3), Bridge Aur Duri / Pulau Aia (section 4), downstream, Bridges Aru Padang (section 5) and Muaro Bridge Siti Nurbaya (section 6 ). In the Upstream, for the parameters pH, BOD and COD in 2011 to 2014 received a range of changes in pH of 6-9, unless the parameters BOD in 2012 of about 4.35 mg/L. In the central region (middlestream), namely BOD content of 4.35 mg/L (2011), 4.54 mg/L (2012), 3.36 mg/L (2013) and 2.56 mg/L (2014), approaching the quality standards was set at 3 mg/L. While the pH and COD are below the quality standards every year. In the downstream, the results of BOD of 17.21 mg/L (2011), 21.25 mg/L (2012), 5.04 mg/L (2013) and 3.42 mg/L (2014). Meanwhile, COD 47.5 mg/L (2011), 57.76 mg/L (2012), 11.17 mg/L (2013) and 20, 5 mg/L (2014), while the quality standards for COD by 25 mg/L, and pH parameters within normal limits. From this research, we reported that watersheds degradation has been in downstream area (section 5 and 6), but in upstream and middlestream was still normally and not degraded.