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Water Supply


Adequate and reliable supplies of clean water are critical to all Illinois residents, Illinois Business and Industry, and to Illinois’ aquatic ecosystems. The Illinois Department of Natural Resources, Office of Water Resources is charged “to study and investigate ways and means by which the various water uses may be coordinated to the end that the water resources of the State be put to their maximum beneficial use and, in connection therewith, to request any department or agency of the State to make surveys, studies, investigations, prepare plans, reports and furnish such data and information as may be necessary.” (20 ILCS 801/5-10(a))

Permits for water withdrawal

Permits are not required for the sole activity of withdrawing water from a ground or surface water source. If the withdrawal involves construction of a permanent intake structure in a public body of water or in the floodway of a stream regulated under IDNR/OWR’s floodway construction rules, a permit will be required per the Rivers, Lakes, & Streams Act (615 ILCS 5). Permits authorizing construction of intake structures in public bodies of water will generally be subject to special conditions restricting the withdrawal of water during periods of low flow to prevent adverse effects on navigation, natural resources or other public interests in the public body of water.

Annual reporting of withdrawals is mandatory in Illinois that pump at a rate of 70 gallons per minute or greater (100,000 gallons per day) per the Water Use Act of 1983 (525 ILCS 45). For more information, please see the Illinois Water Inventory Program webpage.


The state water supply planning program, established by Executive Order 2006-1 and adopted by 2022 Illinois State Water Plan, is dedicated to preserve water sustainability for Illinois residence, business, industries, agriculture producers and the state’s aquatic ecosystems.  In cooperation with Illinois State Water Survey (ISWS), the available quantity of surface water and groundwater is scientifically assessed.  Future water demands of various sectors are estimated with input from Regional Water Supply Planning Committees (RWSPCs), which are comprised of representative of public water supply, power generation, industrial, commercial, irrigation, livestock, and environmental interests.  Water conservation strategies and drought response actions, as well as recommendations to address critical water supply concerns are incorporated into a region-specific and comprehensive plan, which serves as an evolving guidance to the region’s water supply management and practice.

Current Status:

Five RWSPCs, Northeastern, Rock River, Middle Illinois, East-Central and Kaskaskia, have completed their regional water supply plan, which cover approximately 93% Illinois population. The Illinois State Water Survey has developed Tier 1 water supply and demand analysis reports for each RWSPC. These documents are available for public review and comments on the ISWS water supply planning website.  The most recent water supply action plan can be found here. (link to action plan)


Other Water Supply Issues

Wei Han, P.E.
Water Supply Engineer
One Natural Resources Way, Springfield, IL 62702-1271
(217) 782-4819 FAX (217) 785-5014

Water Supply Resources