Public Water Supplies
Part 2 of "Water Resources in Illinois"
Illinois Issues introduction: Today, most people take for granted that a continuous, cheap and safe supply of water will be there upon the turn of the tap. Yet, there is growing concern among hydrologists, chemists, and others in the field of water that both the quality and quantity of tomorrow's water supply may be in jeopardy. The following article examines the public water supply systems in Illinois and the various problems now confronting them as well as some of the possible solutions to those problems.
* * *
To most Illinoisans, water is what comes out of faucets. Like most of their countrymen, they have come to expect that the product delivered via those faucets—for most domestic water is a product, as manufactured as the instant coffee or laundry detergents with which it is used—will be available when needed, safe to use and cheap. Most of the time it is.
Most Illinoisans (88 percent) get their domestic water from public water supply systems, which officially are those which service at least ten customers from a common source and via a common distribution system. (The remaining households and businesses get their water from private wells or, in the case of larger companies, from their own surface reservoirs.)
There are roughly 2,000 public water systems in Illinois, the largest of which is Chicago's Department of Water which supplies about 4.5 million people. Combined, these systems withdrew 1.78 billion gallons per day from the state's rivers, lakes, and wells. These 1.78 billion gallons represent only a tiny fraction of the state's daily average withdrawals; industry (chiefly the electric power industry) withdraws more than 20 times that much. But because people drink it, and bathe in it, and cook with it, the quality and reliability of public water are significantly out of proportion to its quantity.
The most basic water issue of all is, "Is there enough of it?" Illinois is officially described as a "water excess" state. Yet parts of the state face impending supply shortages, in some cases as early as the early 1990s.
Nowhere is this thirsty future arriving faster than in northeastern Illinois. Metropolitan Chicago is watered from a variety of sources. Chicago itself and the towns which either buy water from it or run their own systems—100 in all—take water from Lake Michigan. Other towns more remote from the lake rely on wells sunk like plant roots into either the shallow sand and gravel aquifers which dot the area or into ancient sandstone aquifers which lie roughly 500 feet down. The wealth of water in these stony sponges is huge. The Illinois State Water Survey (ISWS) estimates that the potential daily sustainable yield—the rate at which water withdrawn from wells can be replenished naturally—of all the groundwater sources in the region to be as much as 560 million gallons. (Some state experts disagree, and say the real potential is much lower.)
The problem is that, huge as the resource is, the region's thirst is even more huge. In 1864, pumpage from wells in the Chicago area amounted to an estimated 200,000 gallons per day. By 1980, pumpage was 177 million gallons per day (mgd), an 825-fold increase. On average, withdrawals have exceeded recharge rates every year since 1958; during the boom development years from 1966 to 1979 alone, pumpage rose by 92 percent.
As pumpage rose, water levels in the aquifers have dropped, roughly 850 feet in the last century in some areas. In recent years the drawdown rate has exceeded even this historical average. In parts of DuPage County in the late 1970s the water table sank by more than nine feet per year; in parts of Lake County it sank as much as 14 feet.
Hydrologists call this kind of exploitation "mining" an aquifer. Yields from any wells have already been reduced to close to half their original capacity, and ISWS experts have warned that some of them will cease to be useful water supplies as early as the mid-1980s. A well need not go dry to cease being a viable water source. For instance, as wells are drilled deeper, the cost of pumping water to the surface increases; in some systems, the cost of energy to move water from where it is to where it's needed is the biggest single item in water department budgets.
Municipal water shortages
The prospect of water shortages in a region which is within spitting distance of the largest fresh water lake system in the world seems not merely ironic but insane. But the water problems of northeastern Illinois illustrate one of the axioms of the water business, which is that while droughts are caused by nature, water shortages are caused by people. There is no shortage of water in and around Chicago. Towns going dry could buy water from systems such as Chicago's or Evanston's, tap nearby rivers, or (as one state official has put it) "stick another straw into Lake Michigan."
Expanding municipal water supply systems in a region so crowded by municipals is not as easy as it used to be. Cost is a factor; four suburban cities signed a pact in 1981 to build a 23-mile pipeline connecting them to Evanston's lake-fed water system at a cost of $81 million. Water rates in some towns would have to rise dramatically; in one Cook County suburb the rate for well water has been about 92 cents per thousand gallons, compared to the $2.55 per thousand which it cost for lake water.
However, money isn't the only problem. To understand why requires a history lesson. Until the turn of the century, Chicago dumped its sewage into Lake Michigan, from which it also drew its drinking water. Predictably, outbreaks of waterborne diseases such as cholera and typhoid were common; one such outbreak in 1854 killed 1,454 people, the equivalent of 45,000 deaths in the modern city.
In 1889 a solution was proposed of typically Chicagoan audacity. The newly formed Chicago Sanitary District (forerunner of today's Metropolitan Sanitary District of Greater Chicago or MSDGC) undertook to reverse the flow of the Chicago River through construction of a series of sluice gates and a sanitary and ship canal connecting the river to the Des Plaines River and thus to the Illinois River system. The project required moving more earth than was moved during the construction of the Panama Canal. When it was finished, sewage and storm water runoff was carried via the canal away from the lake by flush water fed into the system from the lake. The city in effect was using Lake Michigan as a mammoth toilet tank, and the Illinois as its sewer.
Protests from neighboring states and Canada over this diversion of lake water began nearly as soon as the project was completed in 1900. (Downstate too; sewage from Chicago wasn't treated as much as it was merely diluted, and the resulting pollution of the Illinois River wreaked havoc on that ecosystem.) In 1930, for example, the U.S. Supreme Court ordered that diversion be reduced by 80 percent. Another suit in 1957 resulted eventually in a further high court ruling in 1967 (which itself was modified in 1980) setting the allowable diversion for domestic, navigation, and wastewater dilution purposes at roughly five mgd. The allocation was to be administered by the Division of Water Resources of the Illinois Department of Transportation (IDOT). Importantly, it allowed the possibility of larger allocations for domestic water use, but only if other reasonable water supply alternatives had been exhausted and if towns receiving lake water adopted certain water conservation practices.
The result is a water situation which Stanley Changnon, chief of the ISWS, has described as "nationally unique." Communities applying for allocations of lake water to replace their ailing wells must justify their requests to IDOT's reviewers, who take into consideration projected population growth, industrial expansion, and the effects of conservation. As a result, suburban Chicago is the only place in the state where water conservation measures have been adopted in times other than drought emergencies.
As is the case with energy, consumers and city halls alike have found that it is possible to "create" new water by saving some of what used to be wasted. The DuPage County city of Elmhurst, for example, was warned several years ago that withdrawals from the sandstone aquifer on which it relied for water would have to be curtailed as early as 1985 if then-current rates of pumpage were not reduced. Elmhurst was awarded an allocation of lake water in 1977. It changed its water rate structure, changed its plumbing code to require water-efficient fixtures, set controls on the summer use of water, and so on. As a result average daily consumption was cut by 15 percent within a year. The drop made it possible to postpone plans for an expensive supplemental well that would have cost $400,000; in addition, the flow of water through the city's sewage treatment plant was reduced so much that it was able to accommodate up to 4,800 new users without expanding.
And will the allocation system eventually bring water supply into line with demand in greater Chicago? "It's not gonna happen," asserts Neil Fulton of IDOT's water resources division. Fulton notes that of the approximately 190 communities which have been awarded allocations of Lake Michigan water, more than 80 have not yet (as he puts it) "turned on the tap." Even if every community which is authorized to do so eventually switches to lake water, Fulton expects pumpage to exceed the practical sustainable yield of the important deep sandstone aquifer by a ratio of two to one. There may be some modest local recovery. But the ISWS, for example, notes that the excess of demand over groundwater supply near Joliet and in the Fox River valley will remain at 40 mgd, with the result that water levels there may reach critical stages as soon as 1990. Unless communities make plans to tap into the now-little used Fox and Kankakee rivers, the state may someday have to resort to a permit system to regulate groundwater withdrawals.
Downstate water woes
Water supply problems may be most dramatic in northeast Illinois, but they exist to some degree across the state. In fact, water shortages are a recurrent crisis in many downstate areas. One can chart the progress of many cities from prairie outposts to industrial centers by charting the changes in their water systems, as first one source then another becomes overtaxed by population growth or is polluted and abandoned. Springfield, for example, drank from a stream, then private wells, then from the Sangamon River; when the river ran dry in the summers the city sank wells into the sandy river banks, only to abandon them in turn for a new man-made reservoir. For the last ten years citizens have argued about whether to replace that supply either by building a new lake, running a pipeline to the massive Havana aquifer some 50 miles away, or damming the Sangamon River.
The problem downstate is not so much a shortage of water as a shortage of storage capacity. Roughly 700 of Illinois's water systems take their water from man-made reservoirs, many of them quite small. Most of them are getting smaller every day. They are filling up with silt washed into them, usually from farm fields in their watersheds. The resulting reductions in storage capacity, coupled with increasing demand by customers, has left many small water systems unable to cope with even modest dry spells.
In the past, the solution to such shortages was simply to rebuild. Rarely did towns take steps to rehabilitate their water systems. New lakes were cheaper, as was raising the dams (and thus the depth) of old ones. Good reservoir sites are scarcer and have made these alternatives less attractive.
That leaves rehabilitation. One can extend the useful life of a lake in several ways. One solution which held promise in the 1950s was evaporation control, by which a monomolecular chemical film is placed atop the lake surface to retard the theft of water by wind and sun; however, evaporation control works well only on small reservoirs and is seldom used today.
Dredging is another alternative, but it too has problems. It is expensive; at Carlinville 20 years ago lake mud was removed at the cost of 27 cents per cubic yard, while costs today range as high as five dollars a yard. The dredged material from some lakes is contaminated by agricultural pesticides and other poisons, and thus poses tricky disposal problems. There may be no land conveniently nearby on which to place the dredged material. Most troubling of all to those who like their solutions permanent is the fact that, unless steps are taken to control sediment inflow at its source, a dredged lake will simply fill up again.
As a remedy to chronic storage problems, in fact, dredging is less cost-effective than applying upstream conservation tillage methods by farmers that control soil erosion. An ounce of chisel plow, in other words, is worth a pound of dredger. But the political and administrative problems facing agencies trying to get sometimes hundreds of landowners spread over as many square miles to undertake expensive conservation techniques for the benefit of an unseen and usually urban population downstream are enormous. Except for scattered experimental programs, few such programs have been attempted.
Siltation is not the only threat to surface water supplies. Lake Eureka in Woodford County had been abandoned in favor of wells because of what treatment engineers refer to as "taste-and-odor-problems" that resulted from depletion of the lake's dissolved oxygen—more commonly known as stagnation. The ISWS installed an experimental aeration device—more commonly known as a bubble-maker—which helped restore the lake's ecological balance, and saved the town of Eureka an estimated $35,000 to $40,000 a year in pumping and treatment costs.
Drinking water standards
As Coleridge once observed in "The Ancient Mariner," the richest supply of water is useless if it is not fit to drink. David Farrell lectures on water matters as part of his job as head of the resource conservation office of the state's Department of Commerce and Community Affairs. He says, "I ask people, 'Consider the trust you show when your child cuts a finger and you instinctively put it under the tap. You're assuming that the substance that comes out of that tap, if not actually salubrious, at least does no harm.”
Insuring that water out of one's tap does one no harm is neither easy nor cheap. In the old days, water treatment was crude, and consisted mainly of chlorine applied in doses strong enough to kill not only bacteria but users' appetite for water. (Even today. a typical consumer will ingest about one milligram of what amounts to bleach in every liter of tap water he drinks.)
Modern treatment technology is vastly more sophisticated. Some federal drinking water standards were on the books as early as 1914. It wasn't until 1974 and the passage of the federal Safe Drinking Water Act that minimum national standards were imposed by the U.S. Environmental Protection Agency (USEPA). These standards (which like most such standards were eventually incorporated into regulations enforceable by the states) set limits on the concentrations of ten common inorganic chemicals, six organic pesticides, bacteria, radioactivity, and turbidity (cloudiness) allowable in public water.
Consistent with the goals of the new laws, the IEPA offers inspections of and training to local water systems and their personnel. IEPA also provides the required testing of water samples at no cost. (Testing for bacterial contamination was required by state law back in 1954; in 1981 IEPA labs ran tests on nearly a quarter-million samples.)
If a water system fails to meet the standards set forth by IEPA, the agency may put the system on "restricted" status. In such cases a system is denied permits for extensions, and is required to make public notice of its failures. Restricted status is reserved for systems which allow water pressure in its water mains to drop, which risks allowing contaminants to enter the distribution system. (Most bacterial contamination of water occurs not at the source but in the distribution system to customers.) Failure to submit water samples for testing is another sin, as is failure to adequately chlorinate water. In 1981 more than 100 systems were placed on restricted status.
Setting "safe" limits on pollutants in drinking water has proven a vastly complex enterprise, not the least because regulators often have had to put the regulatory cart before the scientific horse. It has been the policy of both the U.S. and Illinois EPAs to limit the concentration in water not only of substances which are threats to the public health but those which might be. Often this means setting limits before the precise health risks are clear. This is especially true in the case of suspected carcinogens, since the cancers which would confirm the danger usually will not appear for 20 years or more. Prudence, not proof, has been the standard.
One example is radium. Orland Park in Cook County asked for and got permission in 1981 from the state to continue to use water from two municipal wells in which levels of radioactivity exceeded state maximums. Orland Park officials asserted that the radioactivity posed no immediate health risk, and the IEPA agreed. (Said an IEPA spokesman at the time, people "won't glow in the dark" after drinking the town water.)
However, the argument that the health effects of low-level radiation, if not proven harmful, may be assumed to be benign was turned on its head by some Orland Park residents who wanted the wells closed. They countered that the lack of good evidence about health effects meant that such radiation has not been proven harmless, either.
The Orland Park episode was hardly unusual in Illinois, which makes it all the more revealing. Not just public health but public finance is at issue in such cases. Orland Park could have solved its radiation problem by either softening the water or by mixing it with water from other wells. But the cost of such steps was estimated to be close to a quarter of a million dollars, which the Illinois Pollution Control Board (which sets actual standards for the state and thus alone has the authority to grant variances from them) agreed would work an unnecessary financial hardship on the town.
More troublesome than even these natural contaminants, however, is the catalog of unnatural contaminants associated with farming and industry. Toxic chemicals—heavy metals such as cadmium and lead, pesticides, nitrates, industrial solvents, and the like. There are an estimated 30,000 different chemicals in production in the U.S., 22 of which are known cancer-causers. Some of them inevitably find their way into Illinois water supplies.
The contamination of groundwater supplies is especially worrisome, and not just because seven out of ten public water systems draw their water from wells. Cleaning out a lake is expensive but cleaning out an aquifer is virtually impossible. Contaminants enter aquifers by any of several possible routes, most notably by leaching from leaky landfills. It used to be thought that even contaminated water was purified naturally as it percolated through successive subsoil layers which acted as filters. That is now known not always to be the case.
That is about all that is known about the newer forms of groundwater pollution. Scientists are just now beginning to understand how contaminants travel underground; staff of the ISWS took advantage of a fertilizer spill in 1978 in Morgan County to track the "plume" as it spread through the aquifer. (Their prediction, based on a computer model, that the aquifer would be cleansed of the contaminant within 14 months proved to be an accurate one.)
Because of the lag between pollution cause and effect, it is sometimes difficult to tell when or where pollutants enter underground systems. A novel attempt to reconstruct potential pollution is also underway at the Water Survey, where aquatic chemists have joined with an industrial geographer to locate sites of now-defunct factories, tanneries and similar sources of toxic chemicals. By noting the location of such facilities and the chemical by-products common to each, researchers will be able to assemble a pollution map of the state which may point to potential future trouble spots. (Or as one of the principal researchers puts it, "Prioritize vulnerable aquifers.")
If one talks to experts in groundwater in Illinois, one often is told what they don't know. Michael Barcelona, an aquatic chemist with the ISWS, points out, "If what we know about dissolved organic compounds in most systems were dynamite, we couldn't blow our nose. Ten to 15 percent of all the organochlorine pesticides ever used in the U.S. were used in Illinois. Where are they? Probably in sediments. But what chemical reactions occur in sediments and groundwater? The soluble ones tend to be associated with groundwater. Once they are buried, they are cut off from the oxygen which is needed to return them to their mineral state. They were invented to destroy organisms, after all, so micro-organisms have trouble digesting them."
The risks of toxics to public water supply is considered real enough by water experts, if still unproven. According to a newspaper's investigative report, for instance, since 1970 the death rate from cancer in the Indiana town of Lake Dalecaria, ten miles southwest of Chicago, has been twice the expected rate. Disease experts pointed to formaldehyde in household cleaners which may have been chemically transformed inside septic tanks into bis(chloromethyl) ether, one of the most potent carcinogens yet identified, which then entered wells.
For all the potential dangers inherent in toxic pollution of drinking water supplies, they have yet to be proven a substantial risk in Illinois. Ira Markwood of the IEPA notes that in the several years since his agency began the routine testing of Illinois drinking waters for pesticide contamination, not one sample has shown higher-than-allowable pesticide levels. While he does not dispute the need for vigilance against toxics, bacterial contamination remains a present danger. Toxics might kill you, he notes. Cholera definitely will.
Government budgets are designed only to deal with present dangers in any event, not potential ones. Markwood notes that state budget cuts may force the IEPA to trim its testing program for trihalomethanes and organics in order to maintain its bacterial testing service.
Illinois towns 50 years ago thought they had made their water safe by chlorinating it. Water officials no longer operate on the principle that what you can't taste can't hurt you. In his 1976 book, Chicago: Metropolis of the Mid-Continent, geographer Irving Cutler admired that city's modern new water treatment plants and concluded, "The problem of safe drinking water has been solved." Most Illinoisans would probably agree with that happy assessment, and they would probably be wrong.
"Safe" drinking water is as much a political and economic definition as a scientific one. As the IEPA's Markwood explains, drinking water is a little like riding in an automobile. There is a risk of harm every time you do it. But no one is suggesting banning automobiles because of the risks. It would cost too much. Likewise, there is a point at which making water safer and safer simply costs too much. ●
Sidebar: Chlorination: Is there a choice?
In the U.S., putting chlorine in water is as commonplace as putting salt on steak. Chlorine in one form or another remains the cheapest and longest-lasting means for ridding water of a wide range of pathogens.
Routine chlorination of public water supplies began during the World War I era. The practice was made mandatory in Illinois by the General Assembly in 1975. Commonplace it may be, but chlorination is a subject of some controversy. Ira Markwood heads the public water supply section of the Ilinois Environmental Protection Agency (IEPA). Markwood notes that resistance to the state's mandatory chlorination requirement is substantial among certain smaller communities. Reasons given for opposition to chlorination vary. Some people say it makes their water taste bad; others worry that it causes pathogens present in water mains to "break loose" (Markwood's words)—a suggestion he dismisses as meaningless. Still others insist that waterborne diseases are a thing of the past. Markwood, noting that current samples of Mississippi River water have shown both typhoid and cholera germs present, adds, "Such diseases are a thing of the past—and the present and the future." It's like having a lot of traffic accidents at a certain intersection in a small town. Because of the accidents the city fathers put up a traffic light. After several years without another accident, people start saying, 'See. We don't need that light.'"
Chlorination has become the center of another more disturbing dispute. In the early 1970s a study revealed the presence in Iowa for the first time of mutagens in public water supplies. Mutagens are chemical compounds capable of altering the genetic messages in a cell's DNA. Further studies revealed that chlorination apparently increases the mutagenicity of water, presumably by reacting with certain organic compounds commonly present in so-called "raw" water.
To date, scientists can tell whether a given sample of water is mutagenic, and they can identify the individual compounds present in that sample (a study in Cincinnati counted 460 different chemicals in one sample), but except for a few instances they cannot identify which compounds are the mutagens themselves. Because mutagenicity has been shown to vary with the concentration in water of a class of compounds known as volatile halogenated hydrocarbons, it was thought for a while that these compounds—especially a group known as trihalomethanes, or THM—were the mutagens. It was largely on the strength of this hypothesis that the USEPA in 1980 set a limit of 100 parts per billion of THM in drinking water. Subsequent research suggests that THMs, while quite possibly a part of the process of the mutagen formation, are not themselves mutagenic.
The outcome of this scientific jigsaw puzzle is important because mutagenicity—the ability to change the genetic codes by which cells grow—is considered a clue to the identity of potential cancer-causers. A few studies have suggested a correlation between the drinking of chlorinated water and increased incidence of colon and bladder cancers. Even the possibility that public water supplies harbor cancer-causing chemicals is frightening; that fear is sometimes cited to explain the fact that in many cities bottled water is the fastest-growing drink in supermarkets.
Is it true that, even in the U.S., it is no longer safe to drink the water? The answer is, "Nobody knows." James Johnston is a biochemist at the University of Illinois and one of the nation's experts in the study of mutagens in water supplies. As Johnston notes in a recent paper, "The study of water-borne mutagens is still in its infancy." Mutagens are not new. The raw material from which mutagens are thought to derive is common in most water supplies, occurring naturally as the so-called "humic substances"— complex compounds created by the decay of plant matter. (Certain other "promutagens" which require conversion by mammalian metabolism in direct-acting mutagens, have also been found in city water mains.) It is only new, more refined measuring techniques which have enabled researchers to find what has been in water all along.
Johnston cautions that the procedures by which mutagenic compounds are concentrated for testing are not yet standardized; indeed, the process of testing may bias the result. Some known carcinogens are not mutagenic in the standard tests, while some substances which are strongly mutagenic are known to be only weak carcinogens. In the face of such uncertainties, Johnston warns, a prudent scientific caution is advised.
Furthermore, the links between mutagenicity and cancer are statistical, not clinical. The studies done to date suggesting that link have all been flawed in some important way or another, and the National Academy of Sciences, after reviewing them, state that no conclusions could be drawn on the strength of the studies' evidence alone. (The National Cancer Institute is working on what promises to be the first definitive study of the relationship between chlorinated water and cancer rates.) In short, writes Johnston, "Whether these compounds actually pose a significant threat to the public health has not yet been established."
Even assuming the early epidemiological studies are confirmed, the risks from drinking chlorinated water appear to be small. The excess risk factor associated with drinking such water is about two; for comparison, the excess risk factor among smokers of developing lung cancer is about 20.
Even if an absolute risk to public health is confirmed, there remains the issue of what relative risk to public health is posed by chlorinated water. Chlorination may be hazardous, but not chlorinating may be a lot more so. As Mike Barcelona, a chemist with the Illinois State Water Survey, notes, "Chloroform [a THM known to be a carcinogen in animals] is nasty stuff, but it's a lot less dangerous than typhoid."
That argument has not impressed everyone in Illinois. In 1981, the mayor of the Clinton County community of Germantown shut off the chlorinator of his town's water system, claiming residents had a right to what he called "chemical-free, cancer-free water." (He was fined by the Illinois Pollution Control Board.) In northwestern Illinois, officials of the villages of Orangeville and Oregon circulated petitions asking for exemptions from the state's chlorination requirement rules. Responding to such pressures, the General Assembly in 1981 exempted the state's estimated 300–400 small water systems from that requirement if they can demonstrate a history of uncontaminated water.
The new law was passed with the reluctant approval of the IEPA, which backed it as a compromise to avoid passage of even more generous exemptions. "It's true that you can stop THM by not chlorinating," explains the IEPA's Ira Markwood. "The question becomes, 'Which disease do you prefer? One like cholera that will kill you immediately? Or the one that might kill you 20 years from now?'" ●