Development of Water Management Efficiency for Huai Nam Ri Reservoir to Assess Water Supply and Water Consumption

Abstract

The Huai Nam Ri Reservoir according to the royal initiative is a project to provide water sources for consumption and agriculture in the resettlement area from the construction of Sirikit Dam in 1957. The reservoir is expected to reach its full operational capacity by 2026. This study aims to enhance the efficiency of water management in the reservoir by utilizing the water balance analysis principle through the MIKE HYDRO Basin model, considering both present and future conditions. Based on the current analysis, the irrigated area is 49,883 rai in the rainy season and 38,406 rai in the dry season. Annual reservoir inflow is 93.26 MCM/year, with water demand at 1.75 MCM/year for domestic use and 58.54 MCM/year for agriculture. The study results indicated that based on the MIKE HYDRO Basin model within 29 years, irrigation water shortages occurred in 8 years—5 years during the rainy season and 8 years during the dry season. These findings exceed the acceptable shortage threshold of 20 percent of the study period or 5 years). Therefore, two alternative approaches were proposed for the project. Option 1: Irrigated Area Reduction area to 41,600 rai to ensure that water delivery can be maintained without exceeding the acceptable threshold of water shortages. Option 2 promoting the cultivation of low-water-consuming crops and developing small to medium sized water storage facilities within the community. These measures aim to reduce direct reliance on the water's reservoir sources and enhance water security within the area.