— by Tim Loftus, Northeast Illinois Regional Water Supply Planning, Chicago Metropolitan Agency for Planning
How Many Straws Can Drink From Lake Michigan?
Nearly 6.5 million people throughout Chicago and 200 surrounding suburbs depend on Lake Michigan for their drinking water. However, despite Lake Michigan’s appearance as being an endless supply of fresh water, Illinois is limited by the federal courts to withdraw only 2.1 billion gallons each day from the lake.
As our towns and cities make plans to accommodate the region’s growth projected for the coming decades, an alarming fact emerges: we are already pushing the upper limit of our lake water restriction, and our groundwater resources are being depleted faster than they’re being replenished. It’s quickly becoming clear that in order to meet the demand of a growing population and to maintain a vibrant economy, we need to become much more efficient and thoughtful with our water usage.
We need to conserve now to ensure sufficient water in the future.
The Situation: Lakes, Rivers, and Groundwater Oh My
The geography of northeastern Illinois has made abundant fresh water supplies available to the region’s ever-growing population and, for about three-quarters of them, Lake Michigan is their source of drinking water. Groundwater, from both deep and shallow wells, serves another 20% of our residents and it’s currently the primary source of water for newly-developing suburbs that are located the furthest from Lake Michigan. The remaining 5% of our region’s residents live in communities that draw their water from the Fox and Kankakee rivers.
The Problem: Our Water Supply Is NOT Infinite
Illinois’ withdrawal of Lake Michigan water is strictly limited by a federal court decree. This supply of Lake Michigan water has been able to keep up with new demands, currently serving nearly 200 communities in five counties plus the city of Chicago. The Illinois Department of Natural Resources has committed to continue serving communities currently supplied by Lake Michigan water until the year 2030. Looking past 2030, however, there is uncertainty about how well Illinois’ allotment of Lake Michigan water will be able to meet the needs of a larger population. Additional regional demands for water will also come from communities that may begin to experience shortages of, or quality concerns with, their groundwater supplies. Based on projections for the region’s population growth, the Chicago Metropolitan Agency for Planning (CMAP) projects that Illinois’ demand for Lake Michigan water could exceed the available supply by the year 2050. Further complicating the picture is that our groundwater resources are also at risk. Half of the region’s groundwater-dependent residents draw from deep aquifers, from which water is being withdrawn faster than it is being replenished. These deep aquifers will likely continue to be “de-watered”. The regional water demand scenarios indicate that demand for groundwater from both deep and shallow wells could increase by 43% – 135% within the next few decades.
Communities and Homeowners Need to Work Together to Reduce Water Waste
In an effort to reduce the risk of future water supply shortages, a comprehensive regional water supply planning process was initiated in 2006. Three years of work by CMAP and the Northeastern Illinois Regional Water Supply Planning Group has produced a regional water demand and supply plan that will be released in February 2010. Scientific support was provided by the Illinois State Water Survey and funding support was provided by the Illinois Department of Natural Resources.
The regional water plan aims to ensure adequate and affordable water for all users. Implementing the plan will maintain, if not enhance, the region’s economic prosperity while providing environmental protection and social equity. By March 2010, the public will be able to download this report by clicking on this link: CMAP Water Supply Planning Report.
While water is not currently considered scarce here in northeastern Illinois, research shows that a lot of water is being wasted. The new regional plan projects potential savings based on both conserving water and using it more efficiently. Drinking water providers (primarily municipal governments) can choose from a broad range of conservation practices that save both water and energy.
These practices include community-level infrastructure improvements such as detecting and repairing leaks in water distribution systems, as well as assisting individual homeowners with water-use audits of their homes. Other ways homeowners and municipalities can become part of the solution include replacing older water-wasting toilets, retrofitting showerheads, and evaluating municipal water-rate structures to better reflect the true cost of water delivery. In short, a new way of thinking about what is arguably our most precious natural resource – water – simply must take root.
Green Things You Can Do
- Replace old, water-guzzling toilets with newer high-efficiency toilets that are WaterSense labeled. High-efficiency toilets can reduce your home’s water usage by 18,000 gallons and save over $100 each year on your water bill! But if replacement isn’t an option for you right away, a “free” way to reduce water use in older toilets is to fill an empty milk jug with water and place it in your toilet tank (it displaces much of the water in the tank and thereby reduces the amount of water the toilet uses with each flush).
- Replace your older clothes washer with a WaterSense labeled high-efficiency washer that saves water, energy, and detergent over the life of the machine.
- Reduce outdoor lawn watering – or eliminate the need altogether by landscaping with native trees, grasses, and perennials.
- Install low-flow showerheads and faucets. Find out how much water (and money!) you might save at http://www.epa.gov/watersense/calculate_your_water_savings.html
- Tell your elected officials that you expect them to implement a water-use conservation and efficiency program in your community.
- Install rain barrels beneath downspouts and use the stored rainwater to keep your gardens healthy during summertime dry periods.
- Become better informed about your community’s aging water supply infrastructure, the costs and benefits of water conservation programs, and how these both might relate to your monthly water bill.
To view a WTTW Chicago Tonight video on water supply planning, click on the link below, scroll down to the article “VIDEO: CMAP water supply planning,” and then click on the “more” button to activate the embedded video. Click Here for Video on Water Supply.