ON TO 2050 calls on the region to coordinate shared water supply resources for long-term sustainability and identifies strategies that are particularly relevant for specific sources. The drinking water source coordination local strategy map identifies the different sources of water supply for municipalities in the region in recognition of their unique challenges and management needs.

Lake Michigan

Will county open space.

Access to Lake Michigan water has been critical to regional development and, if well managed, will continue to provide a sustainable supply of water into the future for much of the region. Illinois withdraws, uses, and then diverts Lake Michigan water out of the Great Lakes Basin to the Mississippi River system. This modification resulted in a U.S. Supreme Court Consent Decree {{Wisconsin v. Illinois, 388 U.S. 426 (1967); 449 U.S. 48 (1980).}} that governs Illinois withdrawal of lake water, which is managed by the Illinois Department of Natural Resources (IDNR) {{17 ILAC Ch. I, Subch. H, Sec. 3730}}. As other parts of the region face water quality and quantity challenges, Lake Michigan communities can help make more of the state’s limited allocation available to others in the region by increasing conservation and efficiency and reducing water loss. In fact, advancing water conservation and efficiency are conditions of the Lake Michigan Allocation Program.

Reducing water loss is a key way to reduce water use and effectively increase the supply available for use. Twenty-one percent of Lake Michigan permittees face chronic water loss problems. {{CMAP, An Assessment of Water Loss among Lake Michigan Permittees in Illinois, 2014, https://cmap.illinois.gov/wp-content/uploads/FY14-0071-IDNR-WATER-LOSS-REPORT.pdf.}} Water loss is not only a waste of a valuable resource, but often results in a loss of revenue for the community water supplier, which can hinder their ability to maintain the water system. Communities can tackle water loss in a variety of ways, including use of the American Water Works Associations (AWWA) M36 water audit method. {{CMAP, An Assessment of Water Loss Among Lake Michigan Permittees in Illinois, 2014, https://cmap.illinois.gov/wp-content/uploads/FY14-0071-IDNR-WATER-LOSS-REPORT.pdf.}} Partners in the region, including IEPA, Illinois Section AWWA, and MPC, among others, are providing critical assistance by helping communities advance asset management processes. Demand management – an approach that aims to conserve water by influencing demand – is a critical strategy that community water suppliers throughout the region should use to meet long-term water supply needs.

ON TO 2050 calls for an integrated approach to water resource management, where the region recognizes, values, and manages water as a singular resource that could be almost infinitely reusable if managed properly. Reuse of rainwater and graywater are key strategies to reducing demands on drinking water supplies while also addressing water quality and other wastewater management objectives. Within the Lake Michigan basin, stormwater that once flowed into Lake Michigan is now sent out of the basin by stormwater infrastructure and the altered river system. This stormwater volume, part of Illinois’ allowed diversion of Lake Michigan water, reduces the amount of the Lake Michigan allocation that can be used for domestic purposes. Local governments should promote green infrastructure and other stormwater management best practices that focus on infiltration to help decrease the Illinois diversion volume attributed to stormwater runoff. {{It is important to note that stormwater infiltration and the Lake Michigan stormwater-runoff debit do not form a one-for-one relationship. Some of the stormwater infiltrated in the diverted-watershed could return to rivers and streams as baseflow and still be included in the diversion accounting.}}

Shallow groundwater aquifers

Many communities in the region rely on shallow groundwater aquifers—water held in soil or in the crevices of rock within 500 feet of the land surface. These aquifers naturally recharge through local stormwater infiltration, which gives them a greater ability to recover from short-term overuse, but also makes them susceptible to drought. Shallow groundwater aquifers can also be impacted by contamination, either through over pumping or land based practices that introduce pollutants into stormwater. For example, conventional road and parking lot salting practices are linked to rapidly rising chloride levels in some parts of the region. {{Walton R. Kelly, Daniel R. Hadley, Devin H. Mannix, “Shallow Groundwater Sampling in Kane County, 2015,” Illinois State Water Survey, March 2016, http://www.isws.illinois.edu/pubdoc/CR/ISWSCR2016-04.pdf.}} {{Walton R. Kelly, Samuel V. Panno, Keith Hackley, “The Sources, Distribution and Trends of Chloride in the Waters of Illinois,” Illinois State Water Survey, March 2012, http://www.isws.illinois.edu/pubdoc/B/ISWSB-74.pdf.}}

Communities should work to protect natural areas that contribute to groundwater recharge, either through land acquisition or land use planning techniques that prevent development from impacting these areas. Sensitive aquifer recharge areas (SARAs) are locations that, if developed, could result in water quality declines. McHenry and Kane Counties have mapped the location of SARAs; additional counties should follow suit and local governments can incorporate protection of SARAs in development regulations. Similarly, local governments should revise their own salting practices and promote better salting techniques among private landowners. {{For more information, see resources on winter snow and ice removal developed by McHenry County, https://www.mchenrycountyil.gov/county-government/departments-j-z/planning-development/divisions/water-resources/snow-and-ice-removal. }}

Land use and transportation decisions can generate demand for water that outpaces the natural recharge rate. Shallow aquifer withdrawals in northeastern Kane County and southeastern McHenry County are exceeding the recharge rate, which may result in neighboring wells competing for less water and impacts to nearby streams and rivers dependent on groundwater flows. Working together, land use planners and water utility managers can align local planning efforts with current and future water supply constraints. Assessing forecasted demand scenarios in the context of available water supply and infrastructure capacity can inform local planners about the sufficiency of water supply and encourage actions that conserve water, protect supply, and/or pursue alternative drinking water sources.

Through groups like the Northwest Water Planning Alliance (NWPA), communities are already organizing to protect water resources. NWPA provides a forum for communities to share information and best practices, including landscaping and irrigation practices that reduce water use. Demand management— an approach that aims to conserve water by influencing demand—is a critical strategy that community water suppliers throughout the region should use to meet long-term water supply needs.

Sandstone groundwater aquifers

Many groundwater dependent communities rely on deep sandstone groundwater aquifers— water held in soil or in the crevices of rock more than 500 feet below land surface. Overuse of one of the aquifers—the St. Peter—has been a concern for decades, but is now presenting short-term water availability challenges as withdrawals have grown to twice the estimated sustainable rate. Due to unique geological conditions, this is posing significant risks in western Will County and northern Kendall County, as portions of the aquifer run dry. Municipal water systems, as well as private industrial and commercial wells, could face decreasing yields, increasing pumping demands, and increasing salinity in these locations in the next five to ten years.

Understanding water supply and demand considerations for communities dependent on this resource will be critical in the coming years. Communities should continue to contribute water use reports and well monitoring data to the Illinois State Water Survey to help the region better understand water supply availability. In specific locations where the risk of groundwater desaturation is particularly acute, communities should work with the ISWS to help coordinate withdrawals and review new public or private well proposals.

Working together, land use planners and water utility managers can align planning efforts with current and future water supply constraints. Assessing forecasted demand scenarios in the context of available water supply and infrastructure capacity can inform local planners about the sufficiency of water supply and encourage actions that conserve water, protect supply, and/or pursue alternative drinking water sources. Demand management— an approach that aims to conserve water by influencing demand— is critical for ensuring a long term water supply. Communities and industries in western Will County and northern Kendall County will need to switch to alternative water sources and should explore working together. In fact, communities are already organizing to protect water resources; groups like the Northwest Water Planning Alliance provide a forum for coordination and information sharing.

Mixed groundwater sources

Many groundwater dependent communities rely on a mixture of shallow and sandstone groundwater aquifers. Shallow and sandstone groundwater sources each face unique challenges. Shallow groundwater aquifers can be impacted by contamination, either through over pumping or land based practices that introduce pollutants into stormwater. For example, conventional road and parking lot salting practices are linked to rapidly rising chloride levels in some parts of the region{{Walton R. Kelly, Daniel R. Hadley, Devin H. Mannix, “Shallow Groundwater Sampling in Kane County, 2015,” Illinois State Water Survey, March 2016, http://www.isws.illinois.edu/pubdoc/CR/ISWSCR2016-04.pdf.}}. {{Walton R. Kelly, Samuel V. Panno, Keith Hackley, “The Sources, Distribution and Trends of Chloride in the Waters of Illinois,” Illinois State Water Survey, March 2012, http://www.isws.illinois.edu/pubdoc/B/ISWSB-74.pdf.}} At the same time, overuse of the sandstone aquifers is now presenting short-term water availability challenges as withdrawals have grown to twice the estimated sustainable rate. Due to unique geological conditions, this is posing significant risks in western Will County and northern Kendall County, as portions of the aquifer run dry. Municipal water systems, as well as private industrial and commercial wells, could face decreasing yields, increasing pumping demands, and increasing salinity in these locations in the next five to ten years.

Understanding water supply and demand considerations for groundwater dependent communities will be critical in the coming years. Communities should continue to contribute water use reports and well monitoring data to the Illinois State Water Survey to help the region better understand water supply availability. In specific locations where the risk of groundwater desaturation is particularly acute, communities should work with the ISWS to help coordinate withdrawals and review new public or private well proposals. Working together, land use planners and water utility managers can align planning efforts with current and future water supply constraints. Assessing forecasted demand scenarios in the context of available water supply and infrastructure capacity can inform local planners about the sufficiency of water supply and encourage actions that conserve water, protect supply, and/or pursue alternative drinking water sources. Demand management— an approach that aims to conserve water by influencing demand— is critical for ensuring a long term water supply.

Communities are already organizing to protect water resources; groups like the Northwest Water Planning Alliance provide a forum for coordination and information sharing. Communities should work to protect natural areas that contribute to shallow groundwater recharge, either through land acquisition or land use planning techniques that prevent development from impacting these areas. Sensitive aquifer recharge areas (SARAs) are locations that, if developed, could result in water quality declines. McHenry and Kane Counties have mapped the location of SARAs; additional counties should follow suit and local governments can incorporate protection of SARAs in development regulations. Similarly, local governments should revise their own salting practices and promote better salting practices among private landowners. {{For more information, see resources on winter snow and ice removal developed by McHenry County, https://www.mchenrycountyil.gov/county-government/departments-j-z/planning-development/divisions/water-resources/snow-and-ice-removal}}

Fox and Kankakee rivers

Will county open space.

A small number of communities – Elgin, Aurora, and Wilmington — use the Fox and Kankakee Rivers for their drinking water supply; yet there is potential for these and other rivers to provide a critical source of water to additional communities in the future, especially as groundwater dependent users face quantity and quality challenges. River water use is regulated by IDNR to protect aquatic habitats and can be restricted in times of drought. Additionally, surface waters are subject to pollution and algae blooms that can increase treatment costs and potentially restrict water access. Aurora also relies on sandstone groundwater aquifers to supply a portion of its drinking water.

Enhancing water quality of the region’s river basins will help sustain river water as a viable drinking water source and has the potential to lower water treatment costs. Existing and potential Fox and Kankakee River water users should work together to manage these resources into the future. A number of coalitions have organized along the Fox River, including the Fox River Study Group and the Northwest Water Planning Alliance. Working together, land use planners and water utility managers can align planning efforts with current and future water supply constraints. Assessing forecasted demand scenarios in the context of available water supply and infrastructure capacity can inform local planners about the sufficiency of water supply and encourage actions that conserve water, protect supply, and/or pursue alternative drinking water sources.

Climate change will likely make river conditions more variable in the coming decades. In response to this change, communities will need to implement water demand management strategies, and maintain groundwater supplies for emergencies. Water demand management—an approach that aims to conserve water by influencing demand— is dependent on a variety of factors and should be tailored for each community based on housing type, land use mix and pattern, median home value and income, utility capacity, and local ordinances. Community water suppliers should focus on four foundational strategies: universal metering, water accounting and loss control, water costing and pricing, and information and education. To identify cost-effective demand management strategies, local governments and water providers can compare the cost per unit of water saved through reduced demand with the cost per unit of newly developed water supply.