Hydro-Meterological Study of Budhigandaki Storage Hydroelectric Project

Abstract

Budhigandaki storage hydroelectric project was first detected in 1974 A.D. by SMEC, following the study of the Gandaki River basin; Budhigandaki is one of the most favored due to its high potential and its location in Central Nepal near the main load center. Budhigandaki is a tributary of the Narayani originated from Lark Himal and Ladak Himal in Tibet. The total river length is about 188 km and the total basin area is about 5007 km 2 . Annual rainfall in the Arughat is 2614 mm. Statistical Analysis showed that the 24 hour maximum rainfall for 50 year and 100 year return periods are 160 mm and 173 mm respectively. There are three major flood disaster occurred in Budhigandaki River on 05 Mar 1968, 17 Jun 1968 and 02 Aug 1968. This was caused by LLOF at Lapubensi upstream of hydrological station no 445. The highest flood was 5210 m 3 /s recorded at hydrological station 445. A one-dimensional hydraulic model in HEC-RAS was developed and executed which enabled the analysis of flooding under different scenarios. Hydraulic models coupled with Geographic Information System are powerful tools for quantitative and qualitative monitoring of spatial and temporal variation of flows in the river. For purpose of Elevation-Area-Volume curve it shows the area of 32.87 km 2 .