What Our Water s Worth

Transcription

1 Lake Michigan is the water source of 77 percent of the population of northeastern Illinois almost 7 million residents as of This massive freshwater resource was formed when glaciers began to retreat 14,000 years ago, and settled in its present formation about 4,000 years ago. It s also the only Great Lake entirely within U.S. borders. Illinois shares the shoreline with Indiana, Michigan and Wisconsin. Lake Michigan is 307 miles long and 118 miles wide. With depths up to 923 feet and a volume of 1,180 cubic miles of water, Lake Michigan is the second largest of the Great Lakes and the fifth largest lake in the world by volume. Although water levels in Lake Michigan have fluctuated over thousands of years, a decline in the lake s water level in the last 30 years has been a cause of concern, especially for communities that rely on it for their drinking water. How is Lake Michigan Replenished? Lake Michigan is fed by rivers and streams that drain from more than 45,000 square miles of the four states. Rainfall over the lake counts for more than half water that replenishes it. Additionally, many communities such as Gary, Ind., Milwaukee, Wisc., and Grand Rapids, Mich., withdraw water from Lake Michigan for drinking. When they re finished with it, they treat the effluent and return it to the lake, another important source of replenishment. Illinois is unique in that it withdraws water from Lake Michigan without replenishing it. Due to the reversal of the Calumet and Chicago River systems away from Lake Michigan starting in 1900, most of Illinois water is diverted to the Des Plaines River, and ultimately to Mississippi River and Gulf of Mexico, instead of back into Lake Michigan. Due to the loss of water, in 1967 the U.S. Supreme Court limited the amount of water that Illinois can remove from Lake Michigan to 3,200 cubic feet per second (cfs). After being sued by Michigan for surpassing this limit by as much as 20 percent, Illinois agreed to a Memorandum of Understanding in 1996 that amended the decree to make 3,200 cfs an annual limit and further compensate for this water debt dating back to Currently, Illinois uses about 88 percent of this legal limit. As of 2005, pumpage for drinking water and other treated uses like toilets, fire hydrants, commercial, industrial and landscaping use accounts for 59.8 percent of the diverted water. Stormwater runoff counts for 27.7 percent, with the rest being diverted for discretionary uses, the lock system, leakage into the locks and rivers, and navigation. page 1

2 Stormwater runoff is counted in the diversion calculation, despite the fact it is never put to good use. Much of the precipitation in Illinois that would have drained into Lake Michigan now goes down the drain, through the sewer, and ultimately down the river. Only a very small portion of Illinois land area (100 sq. miles) still drains into Lake Michigan, about one-seventh of the drainage area before the reversal. How do we extract the water? The Chicago Dept. of Water Management (CDWM)Chicago Dept. of Water Management (CDWM) is the major supplier of Lake Michigan water, delivering close to 1 billion gallons of clean drinking water every day to more than 170 municipalities in the area, including Chicago itself. Water is taken in from crib structures that can be seen from shore about 2.5 miles away. The water is then sent to either of two water purification plants, the James W. Jardine or South Water Purification Plant and treated for drinking. CDWM sells water directly to 48 neighboring communities, which then use a portion of the water, but also sell it to western neighbors. Lake Michigan water is used as far west as Plainfield, Ill., which straddles the borders of Will and Kendall counties, approximately 40 miles from the lake itself. Within Chicago itself, there are more than 4,200 miles of pipe for moving potable drinking water. All told, CDWM s distribution system ultimately serves approximately 5.5 million people, all connected to Lake Michigan by thousands and thousands of miles of pipe. An additional 1.5 million people receive Lake Michigan water from either one of Chicago s northern suburbs - some, like Evanston, then sell water to western neighbors, while others, like Kenilworth, do not or in the case of ten southern suburbs of Chicago, including Calumet City and Chicago Heights, actually receive their Lake Michigan water from Hammond, Ind. Regardless of who pumps it, Lake Michigan water is treated by a series of filtration devices, including debris catching screens, chemical treatment application channels, mixing basins to flocculate (collect) solids, and settling basins to let these flocculated solids settle out and be removed. Next, the water is filtered through sand a gravel for further natural polishing, and then treated with chlorine for final disinfection. Other chemicals, including fluoride, are added to the resulting water to exceed U.S. Environmental Protection Agency and Ill. Pollution Control Board standards. Where does the water go when we re done with it? The water from our faucets, toilets, showers, and drains enters a complex pipe system, thousands of miles long. In municipalities with combined sewer systems, such as the city of Chicago, sewer water flows into pipes with rainwater that drains from roofs, streets and parking lots. This combined system increases the load on treatment plants during storms, and heavy storms can cause the sewers to overflow with polluted water in combined sewer overflow (CSO) events. To protect homes and businesses during smaller storms, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) often has to allow untreated wastewater to overflow in the Chicago River System. During larger storm events, the sewage is actually allowed to overflow directly into Lake Michigan. To combat CSO events, MWRD has implemented the TARP deep tunnel project, and many stormwater management agencies are encouraging green practices like downspout disconnection, rain barrel installation, and pervious surface conservation. In separated sewer systems, stormwater drains into a separate pipe system and flows back into the rivers untreated. Although this eliminates CSO events, the stormwater may contain harmful pollutants such as oil, salt, pesticides, sediment, and litter that can pose challenges to healthy waterways. page 2

3 For the majority of the region, this combined wastewater and stormwater is then funneled to one of seven MWRD wastewater treatment plants. MWRD is an independent governmental agency whose service area includes square miles in Cook County. Stickney, the largest wastewater reclamation plant in the world, along with the 6 other facilities, treats waste and stormwater from 126 municipalities, which are home to 5.25 million residents as well as industrial and commercial users. Nearly 1.3 billion gallons of wastewater per day enter MWRD s treatment plants this way. There are other wastewater management authorities such as the North Shore Sanitary District and Lake County Sanitary District, which are comparable to, but much smaller than, MWRD. Some municipalities have their own wastewater treatment facilities. After treatment, most of these plants discharge the water into either the Chicago Area Waterway System or the Plaines River system. These water bodies flow southward, diverting our effluent to the Illinois River, and ultimately to the Mississippi River and Gulf of Mexico. What are the advantages and challenges to using Lake Michigan water? Advantages Lake Michigan is a vast resource that holds approximately 4 percent of unfrozen surface freshwater in the world. If used responsibly, it is a sustainable and renewable resource for the Chicago area. Like other cities in Michigan, Indiana, Wisconsin, and Canada that use Lake Michigan water and return it to help sustain the resource, Illinois communities could too. Water from Lake Michigan is very high quality due to geographic characteristics and tight pollution regulations. This relatively high quality water requires less treatment than many other surface water sources, resulting in fewer residual additives and lower treatment costs. Lake water is easily accessible and reliable through the built infrastructure in the Chicago area, which translates to a consistent supply for consumers. Challenges Demand for Lake Michigan drinking water is increasing as suburban population growth expands and more communities look to move to Lake Michigan Water. Population in suburbs using Lake Michigan water is expected to increase from 2.58 million in 2005 to 3.41 million in Although overall water consumption in Chicago itself has decreased since 1990, the city s population also is expected to grow from 2.48 million in 2005 to 3.36 million in Additionally, an increase in suburban demand requires Lake Michigan water to be pumped further and further from the shoreline, incurring increased costs for pipe and pump infrastructure and higher energy costs to pump over long distances. With a 33 percent population demand increase between city and suburban users, water conservation and reduction of the legally capped diversion will be instrumental in managing increased demand. You can t manage what you can t measure. The majority of single and double family residences in Chicago are not metered, so residents do not know exactly how much they use. When meters are installed, users become more aware of their water usage and tend to conserve, fix leaks, and eliminate waste. Based on programs in other cities, a meter will typically save a resident percent on their water bill. Metering Chicago residences could save 30 million gallons per day, which is enough water to supply another 300,000 people. For more information on getting a meter installed and receiving water rate and conservation page 3

4 incentives through Chicago s MeterSave Program, visit the MeterSave web site. Providing clean drinking water requires a great deal of infrastructure, from treatment plants to pumps and reservoirs to pipes. As pipes age, they form cracks and leaks, leading to inefficiency, lost water, higher stress on pumping facilities, and greater energy costs. Out of Chicago s approximately 4,230 miles of water pipes, 2,700 miles, or 64 percent, are 60 years or older; and some are well over 100 years old. Aging pipe infrastructure in Chicago alone results in 24 million gallons of drinking water lost to leaks per day. That s enough to fill 36 Olympic-size swimming pools every day. Many suburbs have similar aging pipe infrastructure that adds to even greater losses. Energy that is provided mostly by coal-fired power plants is used to pump water to the filtration plants, treat the water, and pump it to the user. Leaking pipes means all the energy used for water was wasted, contributing significantly to costs and unnecessary carbon emissions. Chicago plans to increase its replacement rate of water mains to 75 miles per year, which will catch up to the rate that the oldest pipes were installed between 1890 and the 1930s. By 2016, the Chicago Dept. of Water Management hopes to save 40 million gallons per day with these infrastructure upgrades, enough water for 400,000 additional people. State-of-the-art leak detection devices will also provide surveys of 2,000 miles of pipe in Chicago per year. Because of the combined sewer system, which mixes wastewater and stormwater in the pipes, large storm events sometimes overload the pipes and cause sewer overflows. In, over 6.5 billion gallons of sewage has been released directly into Lake Michigan. In 2008, it was almost 11.5 billion gallons. Find more information here on sewer overflow reversals to Lake Michigan from 1985 to present. Additionally, any stormwater runoff that gets sent into the sewer system deducts from Illinois allowable diversion of water from Lake Michigan. This amount changes every year with precipitation levels, but is generally around 500 million gallons per day a staggering amount of wasted water that could be used for drinking, help groundwater communities ease strain on their dwindling supplies, or simply be returned to and left in the lake. What can you do to be a good steward of Lake Michigan water? Conserve Collect o Calculate your water usage to find out where you can reduce your consumption. o Fix leaks and drips in pipes, toilets and faucets at home, and implement other measures to conserve water at home. o Use WaterSense labeled products that ensure water conservation. o Invest in drought-resistant and native plants, and then adjust your lawn-watering accordingly. Many automatic irrigation systems are programmed for climates with less rain than the Chicago region receives. You can probably dial down both the frequency and volume of your watering. o Sign up for Chicago s MeterSense Program. o Install rain barrels to help catch rain water. It then can be used for landscaping and to help prevent sewer overflows in large storm events. Check out the Chicago Rain Barrel Rebate Program for more information. o Plant green roofs and install more pervious surfaces. Green roofs and pervious surfaces like soil, grass, gravel, or pervious pavement allows rainwater to infiltrate into the ground unlike concrete and asphalt, which direct stormwater to the sewer system. page 4

5 Protect o Properly dispose of oil, chemicals and other contaminants rather than sending them down the drain, which can end up polluting the region s waterways and Lake Michigan. o Properly dispose of unwanted pharmaceuticals through medicine take-back programs. o Road salt can contaminate rivers and shallow aquifers. Investigate green salts and encourage your local government to do the same. Inquire o Does your community have a plan to modernize the water system? Do you have a stormwater management policy? What about programs to assist homeowners with water-efficient retrofits or installing green infrastructure? Most Illinois communities have very good web sites, including information on public works. Check it out, talk to your elected officials and neighbors, and, more importantly, take action. For more information: General Educational Information Water 2050: The Northeastern Illinois Regional Water Supply/Demand Plan MPC s Before the Wells Run Dry: Ensuring Sustainable Water Supplies for Illinois (2009) Water Conservation Tips Field Museum Water Use Calculator More tips on water conservation and use City of Chicago Departments and Initiatives Chicago Department of Water Management (CDWM) CDWM s Water Treatment Education Chicago Water Metering Program Chicago Rain Barrel Program page 5