Evaluasi Daya Dukung Sungai Deli Melalui Kemampuan Proses Self Purification (Point Source: Anak Sungai Simeimei, Kecamatan Namorambe Kabupaten Deli Serdang Provinsi Sumatera Utara)

Abstract

Daerah Aliran Sungai (DAS) Deli merupakan daerah aliran sungai yang mencakup sebagian wilayah yang terletak di Kabupaten Karo, Deli Serdang dan Kota Medan dengan hulu sungainya di Kabupaten Karo (Sibolangit) dan Deli Serdang serta bermuara di Belawan. Penelitian ini dilakukan untuk menganalisis daya kualitas air parameter pH, Suhu, DO, BOD, dan COD di Sungai Deli di Desa Kuala Simeme, Kecamatan Namorambe, Kabupaten Deli Serdang berdasarkan baku mutu kualitas air menurut PP Nomor 82 Tahun 2001, serta untuk melihat daya dukung sungai melalui kemampuan proses self purification. Proses self purification yang terjadi dapat digambarkan dengan kurva pengurangan oksigen dengan persamaan streeter-phelps. Pemodelan streeter-phelps terbatas pada dua fenomena yaitu proses pengurangan oksigen terlarut (deoksigenasi) dan proses peningkatan oksigen terlarut (raerasi). Parameter yang digunakan untuk pemodelan streeter-phelps adalah DO dan BOD. Hasil penelitian menunjukkan bahwa kualitas air di Sungai Deli di Desa Kuala Simeme, Kecamatan Namorambe, Kabupaten Deli Serdang masuk dalam kriteria mutu air kelas II dan dari hasil pemodelan menunjukkan bahwa adanya kemampuan pemurnian diri yang dimiliki badan air dengan nilai purifikasi alami (f) sebesar 4,19 dimana laju deoksigenasi (K) = 1,04/ hari dan laju raerasi (R) = 4,3/hari. Laju rearasi yang tinggi menyebabkan kemampuan pemurnian diri yang dimiliki badan air juga tinggi.

Deli watersheds is a watershed that covers part of the area located on Karo Regency, Deli Serdang Regency and Medan City with upstream of the river in Karo Regency (Sibolangit) and Deli Serdang and empties into Belawan. This research was conducted to analyze the water quality parameters of pH, Temperature, DO, BOD, and COD in Deli River, Kwala Simeme Village, Namorambe sub-district based on water quality standards according to PP No. 82 of 2001, and to see the carrying capacity of the river through the ability of the self purification process. The process of self purification that occurs can be described by oxygen reduction curves with street-phelps equations. Streeter-phelps modeling is limited to two phenomena, namely the process of reducing dissolved oxygen (deoxygenation) and the process of increasing dissolved oxygen (raerasi). The parameters used for streeter-phelps modeling are DO and BOD. The results showed that the water quality in the Deli River in Kwala Simeme Village, Namorambe Subdistrict was included in the class II water quality criteria and from the modeling results showed that there was the ability of self-purification of water bodies with natural purification values (f) = 4.2 where the deoxygenation rate (K) = 1.04 / day and the rate of reration (R) = 4.37 / day. The high rate of rearation causes the body's self-purification ability to be high.