Xi huyi district rainwater source waterproof engineering department. Huyi district airport cross drainage project Xi Huyi district rainwater source waterproof engineering department won the bid. Huyi District belongs to xi, Shaanxi Province, formerly known as Huyi and Huxian County. It is located in the southwest of Xi City, adjacent to Gaoguan River and Fenghe River in the east and ningshan county in Ankang City in the south.