Background Information
The diversion of water from the Lake Michigan watershed is of major importance to the Great Lakes states and to the Canadian province of Ontario. The states and province that border the Great Lakes have concerns with both diversions during periods of low lake levels, as well as the long-term effects of diversion. To ensure that the concerns of these interested parties are considered, the U. S. Army Corps of Engineers (USACE) has been given the responsibility for the accounting of flow that is diverted from the Lake Michigan watershed.
Reporting
An annual report is traditionally published once a year. The annual report will usually contain a diversion accounting report for one or more of the previous years, depending on when the diversion accounting data was ready to be reported. In addition to the annual report, a technical committee report is also published every 5 years.
Agency Responsibility
USACE, Chicago District, is currently responsible for monitoring the measurements and the computation of the diversion of Lake Michigan water by the State of Illinois. In the past, other agencies have been responsible for this task; as a result, some reports by USACE. For example:
- The diversion accounting calculations for water years (WY) 1981 and 1982 were made for the Illinois Department of Natural Resources - Office of Water Resources (IDNR-OWR), formerly known as the Illinois Department of Transportation - Division of Water Resources (IDOT-DWR), by the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC), formerly known as the Metropolitan Sanitary District of Greater Chicago (MSDGC).
- The computations for WY 1983, 1984, and 1985 were performed by the Northeastern Illinois Planning Commission (NIPC) for IDNR-OWR. The Corps reviewed, modified, and updated the WY 1984 and 1985 diversion accounting performed by NIPC.
- The computations for WY 1986 were performed jointly by NIPC and the Corps of Engineers. Computations since then have been performed solely by the Corps of Engineers, with the exception of those for WY 1991 and 1992 which were performed jointly with Christopher B. Burke Engineering, and those for WY 1998 and 1999 which were performed jointly with Mead & Hunt.
- The diversion accounting reports for WY 2000 and WY 2001 were jointly produced by CTE (now AECON) and the Corps of Engineers.
Please contact the Chicago District public affairs office at ChicagoDistrict.PAO@usace.army.mil for additional reports not found in our digital report library.
Technical Review Committee Reports
Annual & Diversion Accounting Reports
Water Year 2025
- No report available at this time.
Water Year 2024
Water Year 2023
Water Year 2022
Water Year 2021
Water Year 2020
Water Year 2019
Water Year 2018
Water Year 2017
Water Year 2016
Water Year 2015
Water Year 2014
Water Year 2013
Water Year 2012
Water Year 2011
Water Year 2010
Water Year 2009
Water Year 2008
Water Year 2007
Water Year 2006
Water Year 2005
Water Year 2004
Water Year 2003
Water Year 2002
Water Year 2001
Water Year 2000
Water Year 1999
Water Year 1998
Water Year 1997
Water Year 1996
Water Year 1995
Water Year 1994
Water Year 1993
Water Years 1990-1992
Water Year 1989
Water Year 1988
Water Year 1987
Water Year 1986
Water Year 1985
Water Year 1983