Illinois Water Supply Planning



Water Supply Management Options

Scientists cannot predict future Illinois climatic conditions with confidence. The historical climate and hydrological records since the nineteenth century show that climate has changed significantly in the past and, even without human interference, could change significantly in the future. More than 20 global climate models produce a wide range of future climatic conditions depending on the modelsí structure, assumptions about future greenhouse gas emissions and land-cover changes, and initial conditions when the model runs are started. Possible future natural and human-modified climate conditions range widely.

A consequence of large uncertainties in future climatic conditions at the regional scale is that there are large uncertainties in future hydrological conditions and water availability. It is difficult for water supply planners and managers to accommodate such a large range of uncertainties. Realistically, it would be expensive to provide water-supply infrastructure that could provide adequate water supplies under scenarios of mean annual precipitation increasing or decreasing by 10 inches by 2100. This is not the same as a drought with one-year precipitation 10 inches below average.

We are faced with a situation in which mean annual precipitation in Illinois could decrease from 38 inches to 28 inches and droughts could diminish precipitation in any particular year to perhaps 15 inches by the end of the century. We do not know the probability of such occurrences.

Facing such uncertainties, a number of strategies could be considered. The first strategy is for scientists to improve climate models and reduce the magnitude of climate uncertainty. The second strategy is for water supply managers to evaluate the capabilities of existing facilities to provide adequate water supplies during severe droughts that have occurred in the past and could recur in the future. Even in the absence of human-induced climate change, more severe droughts are likely to occur in the future than have occurred in the past 30 years, and it would be wise to be prepared. Currently, the ability of many water-supply facilities to cope with worst-case historical droughts is unknown.

The third strategy is to evaluate the capabilities of existing facilities to provide adequate water supplies during even more severe droughts that could occur in the future in association with global warming. Difficult decisions will have to be made when constructing new water-supply facilities. Such decisions will have to consider the risks and unknown probabilities of possible climate changes and the high costs of mitigation strategies, as well as the possible high costs of doing nothing.

It would not be wise for water supply managers to base their decisions on the output of one climate model and one set of assumptions of future greenhouse gas emissions. A large number of global climate models running a range of emissions scenarios provides better expression of the uncertain science behind regional climate change. The large range of natural variations and changes in regional climatic conditions also need to be considered.

Some relevant data sources are provided here.

Challenges in Meeting Increased Demands


Alliance For Water Efficiency

Greenest Region Compact of Metropolitan Chicago: A voluntary initiative of the Metropolitan Mayors Caucus to improve the regionís water, air and land resources. The first priority strategy is residential water conservation.
The Regional Compact (pdf 32kb);
Resolution of Endorsement (pdf 88kb);
Environmental Actions Workbook (pdf 871kb)
Illinois Lake Michigan Allocation Conservation Program (pdf 25kb)
A Drought Resistant Florida (pdf ~1.0mb)
This document evaluates short and mid-term techniques for improved water use efficiency and long-term development of drought-resistant alternative water supplies.
Arizona Water Conservation Office
California Urban Water Conservation Council
The Council was created to increase efficient water use statewide through partnerships among urban water agencies, public interest organizations, and private entities. The Council's goal is to integrate urban water conservation Best Management Practices into the planning and management of California's water resources. For a desrciption of the CUWCC's 14 Best Management Practices, click on Memorandum on their Home Page.
Saving Water Partnership
A website to help conserve water at home and work. Includes case studies, tools, resources, and links. Sponsored by local utilities in Seattle and King County, Washington.
An Analysis of Canadian and Other Water Conservation Practices and Initiatives, Council of Canadian Ministers of the Environment (pdf ~4.0mb)
Analysis of Economic Instruments for Water Conservation, Council of Canadian Ministers of the Environment (pdf ~500kb)
Ideas@work (Vol.4, No. 1): Sensible Water Strategies (pdf ~440kb)
Outlines a range of conservation actions for a range of persons from individuals to industry to municipalities.

Great Lakes Commission Conservation Tool Kit for the Great Lakes Region:

Public Sector Water Conservation: Technology and Practices Outside the Great Lakes-St. Lawrence Region (pdf ~2.8mb)
Assesses the best available technologies and options for water conservation in the public sector outside of the Great Lakes.
Briefing Paper: Summary of Current Water Conservation Practices in the Public Water Supply Sector of the Great Lakes-St. Lawrence Region (pdf ~1.6mb)
Assesses the state of water conservation in the Great Lakes region.
Regional Case Studies: Best Practices For Water Conservation in the Great Lakes-St. Lawrence Region (pdf ~1mb)
Water Conservation Resource Directory.
Water conservation-related links by topical categories including technology, educational resources, organizations, international resources, municipal water conservation programs.
Water House
A web site oriented toward the residential water user.
Water Use It Wisely
An Arizona based web site oriented toward the residential water user.
Water Wiser
An AWWA web site with various water conservation information. Includes a downloadable Water Loss Control program for water utilities.
Water Efficiency
A U.S. EPA web site oriented toward products that are useful in implementing conservation.

East Central Illinois

Northeastern Illinois

Lake Michigan Allocation Conservation Program (pdf 25kb)

Chicago's Water Agenda 2003 (pdf ~1.2mb)


Michigan: Report to the Michigan Legislature (pdf ~0.8mb)
This report describes a water withdrawal assessment process and tool using science as the basis for decision making and designed to respond to new laws to manage large water withdrawals.
Energy, Climate & Sustainable Water Management (pdf ~0.2mb)
A "big picture" look at relationships between these issues, and outlines of some tools for getting to water sustainability.
Ground Water Sustainability: A White Paper (pdf ~75kb)
National Ground Water Association paper outlining strategies for sustainable use of groundwater resources.
A Strategy For Federal Science And Technology To Support Water Availability and Quality (pdf ~3.3mb)
A new (9/07) report from the National Science & Technology Council providing an overview of challenges in the pursuit of adequate fresh water supplies; laying out associated research priorities; and providing recommendations for a Federal science strategy to address this important issue.
Integrated Water Resource Planning (Palmer) (pdf ~0.3mb)
A holistic approach to water system management, combining supply, demand, quality, environmental protection, financial planning and public participation.
The Water Cycle and Water Budgets in Illinois: A Framework for Drought and Water-Supply Planning (pdf ~6.7mb)
The Water Cycle and Water Budgets in Illinois: A Framework for Drought and Water-Supply Planning (pdf ~600kb)
Presentation made on March 14, 2007, at the Illinois Section AWWA Annual Conference in Springfield by Derek Winstanley, Chief, Illinois State Water Survey.
Water Resources Planning: Manual of Water Supply Planning Practices (M50), Second Edition (1/07), AWWA.
Available for purchase through AWWA for $120.00 (non-members) at by typing M50 in the Search Box (upper left hand corner) and clicking GO.


Groundwater (pdf ~0.2mb)
A letter describing the groundwater sustainability policy adopted by the Southeastern Wisconsin Regional Planning Commission

Water Reuse

Water Reuse Association
The WateReuse Association advances the beneficial and efficient use of water resources through the use of reclamation, recycling, reuse and desalination.
Water Reuse: An Integral Part of Sustainable Water Resource Planning (pdf ~2.5mb)
Presented by Paul R. Anderson, Department of Civil, Architectural and Environmental Engineering, Illinois Institute of Technology, Chicago, to the Northeastern Illinois Regional Water Supply Planning Group, July 26, 2007.
Using Recycled Water For Drinking
Evaluates management of health risks, cost effectiveness, the "yuck" factor, and an overview of Australian and international experiences with the indirect potable reuse (IPR) of wastewater.

Watershed Planning

Ideas@work (Vol. 4, No. 2): Watershed Planning for Sustainable Communities (pdf ~1mb)
An overview of watershed planning and how it can be a tool to guide land use decisions and safeguard water supplies.

Water Treatment

An article from The Economist, June 5, 2008.

Illinois State Water Survey

2204 Griffith Dr
Champaign, IL 61820-7463

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