KAJIAN BEBAN PENCEMARAN HARIAN DI SUNGAI CITARUM MENGGUNAKAN PEMODELAN QUAL2K STUDI KASUS: SUNGAI CITARUM SEGMEN KOTA KARAWANG

Abstract

Abstrak: Sungai Citarum merupakan sungai terpanjang dan terbesar di Jawa Barat.  Potensi pemanfaatan Sungai Citarum cukup besar meliputi antara lain: sumber air baku air PDAM, air baku industri, pertanian, perikanan, PLTA, dan sarana rekreasi. Hasil pemantauan kualitas air menunjukkan bahwa sampai saat ini kondisi kualitas air Sungai Citarum belum dapat memenuhi baku mutu air yang telah ditetapkan di sepanjang tahun, terutama pada musim kemarau (SK. Gubernur Jabar No. 39/2000). Berdasarkan hasil penelitian Pusat Litbang Sumber Daya Air (PUSAIR) dan Badan Pengendalian Lingkungan Hidup Daerah (BPLHD) Prov. Jawa Barat Th. 2011, terjadinya penurunan kualitas air tersebut disebabkan oleh peningkatan beban pencemaran dari berbagai sumber pencemar yang berasal dari populasi penduduk, perkembangan industri, ekstensifikasi dan intensifikasi lahan pertanian, pengembangan perikanan, dan populasi ternak. Studi ini dilakukan untuk mengetahui kualitas air serta menghitung beban pencemar di Sungai Citarum Segmen Kota Karawang. Sebanyak 6 sampel dikumpulkan dari 6 titik pengamatan, yang selanjutnya dianalisis di Laboratorium Perum Jasa Tirta II. Metode pendekatan yang digunakan adalah dengan simulasi pemodelan QUAL2K serta perhitungan beban pencemaran harian maksimum. Berdasar hasil studi, diketahui bahwa kandungan pencemar BOD melebihi Baku Mutu Air Kelas II PP No.82/2001. Dari hasil pemodelan QUAL2K dapat diketahui sebaran pencemar di setiap ruas. Hasil perhitungan beban pencemaran harian maksimum pencemar BOD pada kondisi eksisting adalah 4416,6 kg/hari, pada kondisi debit minimum adalah 545,3 kg/hari, dan pada kondisi debit maksimum adalah 3867,7 kg/hari.

Kata kunci: beban pencemaran, BOD,  kualitas air, model Qual2K, pengelolaan sungai.

Abstract : Citarum River is the longest and largest river in West Java. The potential use of Citarum river large enough, including the following: raw water source of PDAM, raw water industry, agriculture, fisheries, hydropower, and recreation facilities. The results of water quality monitoring to the current condition of Citarum River showed that the water quality can not meet the water quality standard that has been set in throughout the year, especially during the dry season (SK, West Java Governor No. 39/2000). Based on the research and Development Centre for Water Resources (Pusair) and the Environmental Management Agency (BPLHD) Province of West Java (2011), the decline in water quality caused by increasing of pollution load from various sources of pollution that comes from the population, industrial, agriculture, fisheries and livestock. This study was conducted to determine the water quality and load capacity pollutant in the Citarum River Segment Karawang. A total of 6 (six) samples were collected from 6 (six) observation point, which is then analyzed in the laboratory of PJT II. The method used in this study is QUAL2K modeling simulation and calculation of the maximum daily load. Based on the study results, it is known that the pollutant (BOD) exceeds the Quality Standard (PP No.82 / 2001, Class II). Based on QUAL2K modeling, it can be seen that the pollutant sources were not evenly distributed in every segment from the 1^st until the 5th segment. The maximum daily load of pollutants BOD on the existing condition was 4416.6 kg / day, on the minimum discharge conditions was 545.3 kg / day, and on the maximum discharge conditions was 3867.7 kg / day.

Key words:  BOD, load capacity of pollutant, model Qual2K, river management, water quality.