SEASONAL POTENTIAL SEEPAGE ANALYSIS OF RAJSHAHI CITY PROTECTION EMBANKMENT, RAJSHAHI, BANGLADESH

摘要

Seepage analysis using flow net construction of 5 locations along the Rajshahi City Protection Embankment (RCPE) reveals that significant amount of seepage was developed during rainy seasons in several specified years. The study was conducted using the water level data of Ganges River from years 1972 to 2002. The average minimum seepage quantity was 28.48 cm~3·s~(-1)·m~(-1) width at Dargapara and the maximum was 64.53 cm~3·s~(-1)·m~(-1) width at Talaimari during this period. During 1987-1988 and 1998-1999, water level at Ganges was above me danger level and the seepage amount was very high (ranging 48.21 cm~3·s~(-1)·m~(-1) to 64.53 cm~3·s~(-1)·m~(-1) width) which caused severe damage to the embankment at Talaimari and Khojapur locations. In some other locations, soil erosion and cracking in bottom of the embankment was also occurred. Talaimari and Khojapur part of the embankment was found to be most vulnerable in terms of safety due to the seepage problems. This study suggests immediate repair works have to be done in the seepage prone areas.