Water Management Improvement for Sustainable Agriculture in Terusan Tengah Lowland Irrigated Area, Central Kalimantan
U. Niatika, Istiarto Istiarto, Benazir Benazir, Yakubson Yakubson
Abstract
Abstract The water of the Terusan Tengah Lowland Irrigated Area (DIR Terusan Tengah) relies on uptake from the nearby anjir canal connecting Kahayan and Kapuas river. A tidal pond is placed at the other side of the main channel to generate a two-way, forward-backward, flow following tidal water in the river. The channel network experiencess sedimentation and the water turns acid. A one-way flow is proposed to increase flow velocity and to flush acid water from the channel network. A collector drain and a series of flap gates are introduced for such purpose. Evaluation of the one-way flow was carried out by flow simulation by using HEC-RAS hydrodynamic software. The simulation reveals that the proposed one-way flow increases the average velocity to 0.14 m/s compared to the two-way flow system with average velocity is 0.09 m/s. This increase will hinder sedimentation. The one-way flow, that is the water flows-in from the main channel and flows-out through the collector drain, guarantees the flushing ot the acid water out from the network.