STUDI SISTEM HIDROGEOLOGI DAN POTENSI AIRTANAH DI DATARAN ALUVIAL PADANG SUMATERA BARAT

• Main Author: Edial, Helfia
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/1443
• Institution: Institut Teknologi Bandung

Padang municipality is situated on the aluvial plain on the edge of Sumatera\'s West Coast. The plain consist of aluvial sediment accumulated by Batang Kuranji and Batang Arau Rivers. The need of fresh water is fulfilled by springs and ground water whichoperated by PDAM. There are eight production wells, namely wells are 3a, 3b, 5c, 7c, A.3P, A.4P, A.5P and A.6P in the of Padang. The industrial growth along with the economic development and the population growth cause the increasing need of fresh water Padang plain has 3 geological unit, first \"aluvial fan\" which situated in the southerm and east part of Padang that forms extensive multi-cycle aluvial, consist of consolidated flufiovulcanic that are mudflow volcanic/lava vulcanic, tuff and andesit that generally covered by layer of pleistosencoarse sand by the thickness between 5-10 m, second coastal sandbarsconsist of 15 low sand dunes isolated with the wider of 3 km situated in the northern part and forms coastal forming in pleistosen period, third \"backswamps\" between pile region, lagoonal deposit dominantly filled with silt to clay sand. There are two kinds of aquifer of Padang Basin, that are unconfined aquifer and confined aquifer, two of the eight wells are positive aquifer (over flow) with the height of ground water level is more than 3 m above ground level. Ground water flows from east to west and north-west, the average thickness of aquifer is 39,35 m found in the depth of 32 m to 243,5 m, permeability (K) value begins from 4, 17 x 10\"5 m/sec to 1,17 x 10-4 m/sec, transmissivitas O.) value begins from 119,62 m²/day to 454,9 m²/day. This region uses the aquifer system with the stream pass through the space intergrain. Recharge area for confined aquifer is situated on aluvial fan (Qf) that is the product of andesit modification from un analyze stream (lava, angglomerat and kolovium sediment) with of 77,1 km2 and infiltration ( recharge) 1.703 mm/year, the potensial of Padang Basin ground water is 117.105,91 m³/day. The amount of water storage (AS) That fills ground level on aluvial fan of Batang Kuranji river is 559,4 mm/year and Batang Arau river -2.108,5 mm/year.