THE REVIEW OF PLANNING DIMENSION CROSS-SECTION IN MARANSI AND LURUIH RIVERS PADANG CITY

Abstract

Flood is a condition of river where the current of water isn’t receive by riverbed, this is because discharge of water happened is bigger than capacity of river. One of region in padang city where often get flood are about Maransi and Aia Pacah, part of Koto Tangah. Flood in these region is largely caused by overflow of Maransi and Luruih river. floods inundated residential areas, rice fields, public facilities and infrastructure are located around the river. Based on rainfall data obtained from the station Gunung Sarik and BMG Tabing Padang in
1988th until 2009th, get average rainfall plan of three method, are Gumbel method, Hasper, Wedwen for repeat period 2, 5, 10, 25, 50, and 100 years are 174,9 mm, 238,9 mm, 287,4 mm, 351,7 mm, 400,1 mm, 449,1 mm. With the inability of the river to accommodate the flood discharge, so that will be plan dimension of cross-section by discharge of water is plan repeat period 10 years use Rasional method as big as 43,71 m3/sec at Maransi river and discharge of water plan repeat period 25 years as big as 90,12 m3/sec Luruih river. There get dimension of trapezoid cross-section Maransi by wide 14 meters, high 2,95 meters and Luruih river by wide 18 meters, high 3,1 meters.
Keywords : Flood, River, Dimension, Cross-section