Pengaruh perubahan tataguna lahan terhadap erosi daerah tangkapan hujan dan pendangkalan Waduk Way Rarem

SUDARTO, Dr.Ir. Bambang AGus Kironoto

2005 | Tesis | S2 Teknik Sipil

Daerah Tangkapan Hujan (DTH) Waduk Way Rarem telah mengalami banyak perubahan tataguna lahan, dari kawasan hutan (1976) menjadi lahan pertanian dan perkebunan (1999-2000). Perubahan tersebut berdampak pada peningkatan erosi lahan, limpasan permukaan dan angkutan sedimen. Pada penelitian ini dilakukan hitungan erosi permukaan dengan Modified Universal Soil Loss Equation (MUSLE). Sedimen hasil erosi permukaan yang masuk waduk dihitung berdasarkan nilai Sediment Delivery Ratio (SDR) menurut metode Kirkby & Morgan (1980). Hasil perhitungan erosi DTH Waduk Way Rarem (1999-2000) sebesar 100,39 ton/ha/tahun atau 5,58 mm/tahun. Dengan pengendalian erosi, laju erosi berkurang menjadi 45,85 ton/ha/tahun atau sama dengan 2,55 mm/tahun.

The catchment area of Way Rarem Reservoir has suffered changes of land use, namely landuse from forest area (1976) becoming agriculture farmland and plantation (1999-2000). Those have resulted in the increasing of run off, sheet erosion and sediment transport. This work deals with estimate of sheet erosion by using the so-called Modified Universal Soil Loss Equation (MUSLE). The subsequently resulting reservoir sedimentation is predicted through the Sediment Delivery Ratio (SDR) determined by using the method developed by Kirkby & Morgan (1980) . Result of computation shows that The catchment area of Way Rarem Reservoir erosion (1999-2000) equal to 100,39 ton/ha/year or 5,58 mm/year. By providing certain erosion countermeasures, the erosion rate reduces to 45,85 ton/ha/year, which is equivalent to 2,55 mm/year

Kata Kunci : Waduk,Pendangkalan,Pengendalian Erosi,Tataguna Lahan,Landuse, Erosion, Sedimentation, Erosion Countermeasure