Factors affecting the water level in Tha Wang Canal Mueang District, Nakhon Si Thammarat Province

Abstract

This research aims to study the factors affecting the water level in Tha Wang Canal, Muang District, Nakhon Si Thammarat Province. The variables examined included daily rainfall, relative humidity, maximum temperature, and atmospheric pressure at moderate sea level. The researchers used secondary data obtained from several sources, including an automated remote water situation monitoring system, the Water Analysis and Assessment Division, the Department of Water Resources, the Ministry of Natural Resources and Environment, and the Southern-East Coast Meteorological Center. For 263 days beginning on January 1, 2023, and ending on October 31, 2023, data was collected every day. A multiple linear regression analysis was performed using stepwise addition of independent variables. The results indicated that both the daily rainfall (X₁) and the atmospheric pressure at moderate sea level (X₄) had a positive impact on the water level in the canal. Conversely, the maximum temperature (X₃) had a statistically significant negative effect on the water level in the canal, with a significance level of 0.05 and the forecast equation is Y=-19.2764+0.0002X₁-0.0578X₃+0.0215X₄

            Daily rainfall, maximum temperature and air atmospheric pressure at moderate sea level  can explain 40.5% variation in water level in Tha Wang Canal and 59.5% of other unstudied factors. Therefore, this forecasting equation is appropriate for estimating water levels in Tha Wang Canal, Nakhon Si Thammarat Province. In order to effectively monitor and address the risks of floods and droughts, it is necessary to maintain the water level in Tha Wang Canal at a minimum of 3.15 meters above the moderate sea level (flood alarm level) and ensure that it does not fall below 0.45 meters above the moderate sea level (drought alert level). This proactive approach is crucial in minimizing the economic impact on the community of Mueang Nakhon Si Thammarat.