The researchers studied changes in the quality of irrigation water in Nam River. They collected samples from seven sites and analyzed them for various chemicals from April to September. The average inorganic concentrations at the sites were pH 7.9, COD 7.3mg/l, EC 0.13dS/m, and more. The highest levels of COD, , and were found in July. The Weola pumping station had the highest levels of COD, , and . The ionic : ratio was higher at the Weola pumping station. The EC was positively correlated with , , , , and .