Monday, September 4, 2006

water 3

A mirage called Lake Michigan
BY PATRICK GARMOE
Daily Herald Staff Writer

How can this be?

How can experts warn of impending water shortages, yet the Great Lakes, the world's largest single source of fresh water, flourish nearby? Forget aquifers and wells - why can't everyone just tap into Lake Michigan? Because history, geology, law and, of course, money all stand in the way.

Lake Michigan supplies water to Indiana, Wisconsin and Michigan as well as Illinois. We, however, live alone under legal limits on how much water we can draw from the lake because we're the only state that takes much more water than we return. Illinois once reciprocated more evenly, but a 1900 cholera epidemic changed things. Sewage flowing down the Chicago River into Lake Michigan was contaminating the water supply, fueling the epidemic. Engineers reversed the flow of the river and built the Sanitary and Ship Canal - removing 673 square miles from the Great Lakes Basin.

The rain and wastewater that seep into that land no longer returned to the lake, flowing westward instead. This redirection of what is called recharge away from Lake Michigan drastically cut into Illinois' contribution to restocking lake water levels.

Decades later, after years of interstate legal wrangling over the inequity of use and return, the U.S. Supreme Court in 1967 set the limits that stand today. While many in Lake County and almost all Cook and DuPage residents rely exclusively on the lake, for those living in the rest of Lake County and all of Kane and McHenry counties, lake water remains little more than a mirage. They're not forbidden from tapping into Lake Michigan, but the hurdles are high.

Gaining access

Lake Michigan feeds 200 water systems in Illinois, filling fish tanks in Chicago's Shedd Aquarium to hot tubs in Hoffman Estates. A complex system of pipes and pumping stations delivers lake water to 7æmillion Illinoisans - more than half the state's population.

That's why the Illinois Department of Natural Resources, the lake's state-appointed guardian, is picky about allowing access. To be eligible, a town has to prove that tapping into the lake would be more cost-effective and practical than tapping into the ground.

"Obviously, as you get farther and farther away from the lake itself and from regional water systems, that test gets more difficult," said Dan Injerd, director of Lake Michigan programs for the natural resources office of water resources.

Among the agency's top priorities is making sure towns already getting lake water have enough to sustain them as their populations grow in the future. Illinois today isn't using all the lake water it's entitled to, in part because we're paying back a water debt racked up in the 1980s, when we exceeded the court-imposed limit.

The state is making good progress paying down the debt, Injerd said, in part because infrastructure upgrades in Chicago are preventing the waste of water through leaky pipes and hydrants. Once the debt is repaid, the state will have more flexibility to meet the water demands of the northeastern Illinois communities.

Counting the costs

Still, outlying towns can convince state officials that lake water is the ideal option. High radium levels in the groundwater made deep wells an undesirable water source for Plainfield, 30 miles away from the lake on the outer edge of Will County.

The fast-growing village has spent almost $8 million to run two miles of a 20-inch pipeline to Bolingbrook and build water storage and pumping stations, said Derek Wold of the engineering firm Baxter and Woodman, which consulted on the project.

Luckily for Plainfield, the Illinois American Water Co. had built a $40 million, 42-inch pipe to run from Bedford Park to Bolingbrook for the specific purpose of selling water to interested communities. Plainfield got its permit in 2001. The new infrastructure remains under construction.

The group approach

Six communities in suburban Cook County took a different route. Twenty years ago, Hoffman Estates, Mount Prospect, Elk Grove Village, Streamwood, Hanover Park, Rolling Meadows and Schaumburg banded together to create the Northwest Suburban Municipal Joint Action Water Agency.

Together the towns built a $120 million system to connect to Chicago's water supply and distribute the water to the participating communities, said Joe Fennell, the agency's executive director.

The project included 54 miles of transmission mains, a large pumping station near O'Hare International Airport and several smaller pumping stations along the route to maintain the pressure to move the water along.

With the luxury of lake water, however, came a responsibility not to waste it. Each community had to adopt strict conservation practices to ensure they weren't wasting water through leaky pipes and hydrants or through evaporation by watering lawns in the middle of the day.

"In return, there's no worry about wells drying up or the water table dropping," said Kenneth Hari, Hoffman Estates' director of public works. "Plus, there's low hardness, and it's a more high-quality product."

Watching the limit

Even if a town has the wherewithal to access the lake, the state must ensure new allocations won't one day harm compliance with federal law.

That means figuring out if bringing one town online will prompt several more to follow suit and factoring in how weather patterns affect the state's removal of lake water, so its level doesn't dip excessively.

Lake experts also carefully watch the water level underground, as the two sources are interdependent. Lake Michigan is partly fed by groundwater that seeps into the lake, so when communities in the outlying suburbs overuse the aquifers, they leave less to replenish the lake.

The relationship also can be beneficial, however, as towns that switch to lake water are required to stop using their deep wells. This relieves the stress on groundwater, said Jeff Wickenkamp, a member of the Southern Lake Michigan Water Supply Consortium.

A finite source

Such was the case in 1980, when an amendment to the Supreme Court decree allowed Illinois to grant Lake Michigan water to 86 more municipalities in DuPage and Cook counties. The deep well levels in the areas had been declining as a result of rapid growth and the water quality was suffering. The mass switch from groundwater to lake water allowed water levels in the deep aquifer to rise.

Unfortunately, Wickenkamp said, recent growth in places like Kane County are causing the aquifers to again approach the low levels of the late 1970s. Geologists until now have had trouble seeing anything but a fuzzy picture of how much water is truly hidden in the rocks. Therefore, ultimatums demanding change can't be issued. "The science is not there to definitively go to a town and say, 'You're not doing what you need to be doing,'æ" said Wickencamp. And in the end, Injerd says, Lake Michigan itself is a finite resource and can't be the only answer. "Obviously, we don't have an endless supply," Injerd said. "And at some point it's possible we'll have to say, we're really tapped out."

No comments:

Disqus Shortname

Comments system