Iron deposits in drinking water systems can increase chlorine consumption and the formation of harmful compounds called trihalomethanes (THMs). A study developed a model to show how iron deposits affect chlorine reactions, considering factors like the type of deposits and the amount of chlorine present. The presence of iron deposits accelerates the reaction between chlorine and organic matter, leading to higher THM formation. The more iron deposits there are, the more chlorine is needed, especially with certain types of organic matter. After 168 hours, deposits contribute to around 20% of chlorine consumption and 37% of THM formation. This research highlights the importance of managing iron deposits in drinking water systems to maintain water quality.