70 ILCS 605/4-45
If a flood prevention district has been formed under the Flood Prevention District Act, the flood prevention district shall have the exclusive authority within such areas as designated by the county board to restore, improve, upgrade, construct, or reconstruct levees. If any part of the territory of a drainage district, levee district, or sanitary district overlaps with the territory of a flood prevention district, the drainage district, levee district, or sanitary district shall, at the direction of the county board, operate under the direction of the board of commissioners of the flood prevention district with respect to the restoration, improvement, upgrade, construction, or reconstruction of levees and other flood control systems. At the direction of the county board, the flood prevention district and its assignees shall be permitted to utilize any property, easements, or rights-of-way owned or controlled by the drainage district, levee district, or sanitary district. In addition, at the direction of the county board, the board of commissioners of any such drainage, levee, or sanitary district must comply with any requests for information by the board of commissioners of the flood prevention district, including, but not limited to, requests for information concerning past, present, and future contracts; employees of the drainage, levee, or sanitary district; finances of the drainage, levee, or sanitary district; and other activities of the drainage, levee, or sanitary district. This information must be submitted to the board of commissioners of the flood prevention district within 30 days after the request is received. Nothing in this Section 4-45 or in the Flood Prevention District Act shall preclude or prohibit a drainage district, levee district, or sanitary district that overlaps the territory of a flood prevention district from conducting or performing its normal operation and maintenance of levees under their control, provided such normal operation and maintenance does not interfere with or inhibit the restoration, improvement, upgrade, construction, or reconstruction of levees and other flood control systems by the flood prevention district.
70 ILCS 605/4-45