Health & Human Services

Guide to Clean Water: Keeping it Fit to Sip

The new rules on safe drinking water are both better and worse for states and localities.
by | December 2000
 

Here's the good news: Under the recently revised federal Safe Drinking Water Act, state and local regulators have lots of flexibility. They can set their own priorities for improving the quality of the water they drink.

Here's the other piece of news: In coming to terms with the new rules and regulations, local governments--and their customers--will spend billions of dollars to change how they collect, treat and distribute drinking water.

When the U.S. Congress revised federal law four years ago, it aimed at creating a more orderly process for cleaning up the country's drinking water. The new law prods the U.S. Environmental Protection Agency to take a more careful and scientific approach to setting and enforcing federal standards. But states and communities are finding that those changes still don't spare them from potentially colossal costs to keep water fit for consumption.

Despite increased flexibility for localities, the law requires EPA to keep moving ahead with elaborate new rules that will force municipal agencies to safeguard their supplies--now including groundwater as well as surface sources from rivers and lakes--and treat water more rigorously before piping it to homes and businesses. Over the next decade, drinking water systems will "end up confronting all the more difficult contaminants we haven't had the willpower to deal with before," says Vanessa Leiby, director of the Association of State Drinking Water Administrators. "All these issues coming along are going to make them invest heavily."

As a first line of defense, the law orders states and communities to start monitoring source water supplies and protect them from being polluted. Depending on what impurities they find, local agencies could be compelled to overhaul the technological processes they use to cleanse the water they supply communities.

Threats to water supplies are real. Seven years ago, 40 people died after Milwaukee's water supply was contaminated by the hard-to-control Cryptosporidium parasite. Santa Monica had to shut down seven wells that provide half of its water when they turned out to be contaminated by methyl tertiary butyl ether, or MTBE, a gasoline additive for curtailing auto tailpipe emissions. Regulators agree that the groundwater that other communities drink already contains threatening levels of naturally occurring but potentially dangerous elements such as arsenic. If these problems aren't vexing enough, the chlorine that systems have been using for decades to disinfect tap water is itself creating new, equally serious hazards.

EPA, state environmental agencies and municipal water suppliers are now negotiating intensely over how aggressively the country should deal with these multiple perils. Not all water systems will be equally burdened, but setting standards contaminant by contaminant could still saddle cities and counties with uncoordinated drinking water directives that don't take cumulative costs into account. And governments still haven't resolved an all-too-familiar quandary: How can states and communities afford to comply with an ever-expanding sequence of federal drinking water edicts?

According to some estimates, over the past 14 years EPA has imposed or at least proposed 13 complicated regulations that commit the country's 55,000 water-supply systems to installing nearly $30 billion worth of filtration and chemical treatment systems. Furthermore, it could cost communities more than $7 billion a year to keep that sophisticated equipment operating.

When Congress revised the safe drinking water law in 1996, it hoped to get away from the steady stream of expensive rules, many based on uncertain science, that had enraged public officials in the early 1990s. So, the new law directs EPA to improve the scientific evidence it employs and focus first on the highest risks from contamination. The law also shifts the focus toward preventing pollution by requiring state agencies to map out community water-supply sources and protect them if that's necessary. EPA and state officials who administer water standards got more flexibility to let small systems use cheaper alternative control techniques, and Congress approved $1 billion a year for state revolving loan funds specifically for drinking water improvements.

State water officials say drinking water regulation has begun working more smoothly as EPA implements the 1996 amendments. Federal officials have backed away from a proposal requiring that all groundwater supplies be disinfected, for instance, and they've rewritten other rules to authorize states to waive monitoring requirements for communities where the contaminants being controlled have never been shown to exist. The total command-and-control approach is evaporating. THE

TREATMENT ANGLE

Shifting attitudes help, but they don't get communities off the hook for dealing with drinking water problems. Over the years, EPA has directed public water systems to meet maximum contaminant levels for 80 common microbes, elements and man-made chemicals and has now identified 61 additional contaminants that may need to be regulated. The law requires officials to pick five for review by next August to determine whether federal standards are necessary.

Meanwhile, for the past eight years, EPA has been negotiating intensively with state pollution-control agencies and local water utilities on a cluster of new rules that could transform how communities treat drinking water. For nearly a century, U.S. water systems have relied primarily on chlorine disinfection to eliminate waterborne diseases--controlling dysentery and virtually eradicating typhoid and cholera. With new threats posed by Cryptosporidium and other contaminants emerging, traditional treatment is no longer adequate to keep some water safe for consumption.

Cryptosporidium spores, for instance, are proving impervious to chlorine, and they're so small that scientists have trouble detecting their presence. "That's a tough one; we can't really even measure it yet," says Janice M. Skadsden, water-quality manager for the Ann Arbor, Michigan, water utility.

Two years ago, EPA approved new regulations requiring systems that use surface water to supply 10,000 or more people to strengthen controls over waterborne pathogens. The tools include covering new reservoirs, reducing water-clouding turbidity that can mean Cryptosporidium is present and upgrading filtration processes to physically remove as many of the parasites as feasible. The agency is now following up with rules extending those enhanced microbial controls to smaller communities. A separate regulation will set procedures that treatment plants must follow when backwashing filters to remove contaminants that have built up. For the first time, another proposed rule would compel communities to start monitoring--and if necessary, start disinfecting--water they draw from belowground aquifers.

Over the past two decades, however, evidence has mounted that chlorine itself reacts with vegetation and other minute organic material in water to form by-products that can cause cancer or reproductive disorders. While concentrations are low, EPA is working with water-supply officials on a set of regulations that attempt to hold down those long-term risks while keeping water free of the immediate threats posed by disease-causing organisms. "You have to use a disinfectant, but you don't want to go too high; and you also have to control the by-products," Skadsden notes.

Even as it tightens treatment requirements, EPA has begun setting limits on the amount of disinfectant water systems use and how much of their chemical by-products can remain in treated water. But the way water systems go about improving treatment to control disease-causing organisms will obviously influence how much disinfectant they use and what dangerous by-products they'll be creating. Recognizing the connection, EPA coupled development of tighter microbial contaminant goals with new controls on the use of disinfectants. That process, begun in 1992, has given local agencies advance notice to balance those risks as efficiently as possible in upgrading treatment systems.

"We knew that this was coming," Skadsden notes, so Ann Arbor four years ago considered a number of options for improving its Huron River water supply. The city debated switching to groundwater but concluded that the cheapest step was replacing chlorine treatment with a more effective ozone disinfection process as part of an $18 million upgrade of its treatment plant. A relatively new technology in this country, ozonation controls organisms, including Giardia and Cryptosporidium, more effectively than standard chlorine treatment and creates fewer by-products.

The process adds ozone to water and then sends an electric charge through it to inactivate disease-causing organisms. The process alleviates taste and odor problems but is four times more costly than conventional chlorine treatment and vastly more complicated to operate, Skadsden says. And it is not a perfect solution. Ozone can react with bromide in water to form bromate, another known carcinogen, and it causes more corrosion in distribution pipes. Other cities that have also turned to ozone treatment for at least part of their water supplies are Los Angeles, San Francisco, Seattle, Dallas, Oklahoma City and Milwaukee.

More expensive innovations are in the works, including advanced membranes for filtering out health-threatening cysts and viruses. In 1997, Marquette, Michigan, installed a $7.6 million microfiltration membrane system that uses polypropylene mesh to disinfect up to 7 million gallons a day of water from Lake Superior. The treatment plant still relies on chlorine to remove viruses that get through the membrane, but "it's worked out pretty good so far," says Roger Olson, the city's water superintendent.

EYES ON THE FUTURE

The recently imposed improvements probably won't be enough to entirely eliminate threats to drinking water safety. In September, EPA- sanctioned negotiations produced agreement on follow-up regulations that will eventually force even more dramatic improvements in treating water supplies.

Those tentative proposals will require operators to monitor their systems even more intensively for disinfection by-products and for microbial threats, notably Cryptosporidium. One objective is to make sure that by-products stay below maximum levels throughout distribution systems, so consumers get equivalent protection no matter how close or far they live from treatment plants. In addition, utilities will need to move more aggressively to determine whether Cryptosporidium exists in the watersheds that provide their supplies. If it's there, they'll have to figure out ways to get rid of it.

Where the parasite is found, the advisory panel recommends that water systems select steps from a toolbox of possible treatment measures, including ozonation, membranes and advanced filtration systems. Eventually, however, many observers think water systems will need to count on ultraviolet light systems that researchers have shown will kill or disable Crypto spores.

Ultraviolet systems already are used to decontaminate sewage wastewater, and European communities are now applying the technology to drinking water disinfection. When the current rulemaking process began, water utilities feared that EPA would require them to turn to UV technology that's never been demonstrated to be practical on a scale large enough for treating major drinking water supplies. Because of those concerns, the negotiated agreement stresses watershed protection, orders accelerated Crypto monitoring and sets forth a menu of treatment options that include improving conventional chlorine disinfection.

Ultraviolet disinfection will be most practical for small communities that draw on groundwater, but UV could be the most effective way for bigger cities to combat the Crypto threat. Seattle is considering the addition of an ultraviolet system to an advanced ozonation plant the city is planning for its Cedar River watershed, and EPA is encouraging experiments with the technology. "This is definitely cutting-edge stuff they're doing," Ann Arbor's Skadsden says. "EPA is hoping that UV will be viable as an option for treatment."

Federal regulators are scheduled to adopt final regulations in 2002, and the negotiated agreement allows eight more years for monitoring and experimenting with new treatment methods. As the combined new rules go into effect, "most surface water systems will go to some alternative disinfection type," says Rene Pelletier, the New Hampshire Environmental Services Department's resource program manager. "It will be a big issue."

ARSENIC AND OLD ROCKS

Although most major cities rely heavily on rivers and lakes, 53 percent of all U.S. localities, including most small-town and rural areas, tap groundwater resources for drinking water. Up to now, regulators have assumed that water protected by rock and filtered by soil doesn't need as much attention. But 31 states have reported that some groundwater has been contaminated by MTBE, and EPA's new standards will require municipal systems to start testing for bacteria, microbes and other health threats if state officials think they might be present.

A congressional deadline is, in fact, forcing EPA to rush to tighten a 58-year-old standard for arsenic, the poisonous and cancer-causing element that seeps from rocks into water supplies. Federal regulators have proposed slashing the limit by 90 percent, a level that municipal water officials say would force Los Angeles, Phoenix, Albuquerque, Kalamazoo, Michigan, and more than 6,000 smaller systems to spend as much as $1.5 billion a year to remove arsenic that seeps into their water from surrounding soil and bedrock. As drafted by EPA, the arsenic standard could force some Southwestern and New England cities and towns to raise water bills by $100 to $200 annually, the American Water Works Association (AWWA) has calculated, even though the agency's scientific evidence is inconclusive. Congress moved this fall to grant a six-month extension to the deadline.

Meanwhile, state and local officials aren't convinced that federal regulators can justify what it would cost communities to comply. In El Paso, Texas, for instance, city officials estimate it would cost $146 million to install sophisticated filtering systems to meet EPA's proposal. Albuquerque, as well as Scottsdale and Sun City in Arizona, also has unusually high levels, as do a number of Southern California cities. The Southwest's hard, high-sulfur groundwater makes removing the arsenic more expensive.

Arsenic contamination may be a threat in the upper Midwest and New England, depending on the geologic formations that water is pumped from. In Wisconsin, water from hundreds of private wells in Outagamie, Winnebago and Brown counties has tested high in arsenic, and scientists think concentrations are rising as groundwater pumping intensifies and arsenic is drawn from bedrock. With some of the highest arsenic concentrations in the world, Wisconsin has tried drilling wells into deeper rock formations, but that hasn't solved the problem for individual homeowners. Special filtration systems on home water taps cost $800.

Forty community water systems in Massachusetts have arsenic problems, notes David Terry, director of the state's drinking water program, and neighboring New Hampshire has more than 100 water utilities where concentrations exceed EPA's proposed standard. "We do have hot spots where it's in the bedrock," notes Pelletier. "A lot of the public water systems affected are in very poor communities."

PAYING THE BILL

By AWWA's account, water systems have already taken on more than $1 billion in capital costs and nearly $2.7 billion in annual expenses to comply with rules that EPA issued under the 1986 version of the law. The 1996 amendments may be more flexible, but the association predicts suppliers could have to finance more than $25 billion in new investments and an additional $6 billion in yearly costs, depending on how arsenic and other treatment questions are settled.

The need to comply will force municipal governments to think creatively about how to come up with the money. In addition to tightening contaminant limits, the 1996 law mandates better training for treatment operations staff. It also requires that water utilities demonstrate the financial capacity to upgrade and maintain treatment plants and distribution systems.

As things stand, EPA reports that nearly a third of the nation's smallest water systems barely cover daily operating expenses, much less invest in better water quality. That's one reason why the number of separate drinking water systems has fallen steadily: Communities are combining operations and selling to private water companies better equipped to deal with complicated EPA standards. "Frankly, with all the new requirements coming along with the '96 law, it makes sense for people to sit down and evaluate the cost of trying to comply on their own," Leiby says.

Others are turning to the private sector to meet the burden of upgrading water-delivery systems. Several large cities contract out some water treatment operations, and large private water service companies, including big multinational firms, are now bidding to help municipal governments meet long-term water-service obligations. Moreover, a 1998 survey of 220 communities conducted by the consulting firm R.W. Beck Inc. found that 35 percent were considering some form of public-private partnership for water treatment.

There are some creative partnerships. When Seattle figured out what it would take to filter the amount of water it needs from its Tolt River watershed, the city took advantage of a new state law authorizing alternative contracting procedures. By using a design- build-operate approach rather than the conventional bidding process, Seattle's Public Utility saved an estimated $70 million through a contract under which a joint-venture company will build and operate the city-owned plant.

When he looks at the unavoidably high costs of upgrading treatment systems, Dave Hilmoe, the Seattle Public Utility's water quality and supply director, points out that if his utility "hadn't been taking advantage of an alternative process like design-build-operate, I don't think we'd be doing our ratepayers any favors."

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