Abstract: By analyzing the foundation sand and water quality of relief wells at Lijia garden  segment of Yangtze Rive main dike in the south of Jingzhou, it’s found that large content of iron and iron compounds in  water is the main cause of chemical clogging of relief well. According to international and domestic drinking water quality standards, the iron content in drinking water should not exceed 0.3 mg/l. It's crucial to reduce iron content in the water to solve rural drinking water problem along the dike and to reduce chemical clogging and protect dike safety. Based on previous studies, physical and biological methods including microfiltration, aeration, and enzyme purification are proposed to purify the water in relief well. This research is of great value for dike safety and rural drinking water along the dike.

Key words: relief well, drinking water, water quality standard, chemical clogging