Water quality control refers to the processes and measures taken to ensure that water is safe for human consumption and environmental health. This involves monitoring various parameters such as pH, dissolved oxygen, and the presence of contaminants like heavy metals or bacteria. Regulatory agencies set standards to maintain water quality in sources like rivers, lakes, and groundwater. Effective water quality control includes regular testing and treatment methods, such as filtration and chlorination, to remove harmful substances. It also involves protecting water sources from pollution through land use management and public education. These efforts help safeguard both public health and ecosystems.