Kajian Hubungan Intensitas Hujan – Limpasan pada Plot Uji Berlereng dengan Permukaan Kedap Air

Abstract

The rapid development of infrastructure development causes the reduction of land catchment areas. As a direct impact, the greater the runoff that occurs along the flow. Observations to determine the relationship between rainfall intensity, slope and runoff were carried out through field experiments. The experiment was carried out on a test plot scale with a rain simulator that could adjust the rainwater pressure and the slope of the test plot so that it was close to the actual conditions in the field. Observations were made by varying the intensity of rain and 3 variations of the slope of the test plot, namely: 0%, 2% and 5%. The results of the observations show the coefficientof determination of the relationship between rain intensity and runoff using the exponential function in the strongest excel software at the slope of the test plot of 0% (flat) with the coefficientof determination R2 = 0.8455. The greater the slope of the test plot, the smaller the value of the coefficientof determination.Perkembangan infrastruktur pembangunan yang pesat menyebabkan semakin berkurangnya lahan tanah resapan. Sebagai dampak langsung maka akan semakin besar limpasan yang terjadi di sepanjang aliran. Pengamatan untuk mengetahui hubungan antara intensitas hujan, kemiringan dan limpasan dilakukan melalui percobaan lapangan. Percobaan dilakukan pada skala plot uji dengan alat simulator hujan yang dapat diatur tekanan air hujan dan kemiringan plot uji sehingga mendekati kondisi sebenarnya di lapangan. Pengamatan di lakukan dengan memvariasikan intensitas hujan dan 3 variasi kemiringan plot uji, yaitu : 0%, 2% dan 5%. Hasil pengamatan menunjukkan nilai koefisien determinasi hubungan intensitas hujan dengan limpasan menggunakan fungsi eksponensial pada software excel terkuat pada kemirigan plot uji 0% (datar) dengan harga koefisen determinasi R2= 0,8455. Semakin besar kemiringan plot uji, semakin kecil nilai koefisien determinasi.