Water: a paradigm for protection.

Protecting the nation's water supply is an ever-changing challenge--and one that requires new paradigms, according to participants at the October 2003 workshop From Source Water to Drinking Water: Emerging Challenges for Public Health, sponsored by the Institute of Medicine's Roundtable on Environmental Health Sciences, Research, and Medicine. "The need for creative thinking and innovation in drinking water science, policy, regulation, and legislation has never been greater," said Frederick Pontius, president of Pontius Water Consultants, which advises water utilities, industry, businesses, and regulatory agencies.

The workshop, the fourth in a series on a variety of environmental health topics, focused on identifying issues critical for protecting the water supply at all stages, from the water in our aquifers to the cool drink coming from the kitchen tap. Speakers and participants identified environmental areas--including the natural, built, and social environments--that impact the nation's ability to ensure safe water. Urban sprawl, rapid population growth, non-point source pollution, and unregulated contaminants were noted as key emerging challenges. Other difficult issues include protecting sensitive sub-populations, achieving sustainable water systems, providing affordable drinking water for systems that supply a single house or development (as opposed to a whole community), and controlling emerging waterborne pathogens.

Critical Gaps

The Safe Drinking Water Act and Clean Water Act have made significant progress toward safeguarding the nation's source and drinking water, but as these pieces of legislation have evolved through reauthorizations and amendments since their enactment in the 1970s, gaps have arisen in the infrastructure. The lack of coordination between the acts' targets, approaches, and regulatory framework have resulted in public health being neglected, said Joan Rose, Homer Nowlin Chair in Water Research at Michigan State University.

For example, planning of integrated watershed protection efforts is supported under the Safe Drinking Water Act, which is aimed at controlling key pathogenic waterborne microorganisms using a risk assessment approach including concerns for sensitive populations. However, enacting the tools for implementing such controls--such as permitted discharge limits and total maximum daily loads (how much of a particular pollutant a water body can assimilate without violating state water quality standards)--fall sunder the Clean Water Act.

Gaping holes exist in monitoring of contaminants, especially pathogens. "Fundamentally, we're in crisis," asserted Jeffrey Griffiths, an associate professor of family medicine/community health and of medicine at Tufts University. The United States has no ongoing, national-scale epidemiologic surveillance, he says, only scattered individual projects. "In terms of drinking water, the monitoring that is going on is extremely limited," he said. "We're just looking at basic quality indicators. We essentially ... don't know what is going on."

There is a real need to seek out integrating themes to revamp disjointed policies and management practices. "We need to develop an integrated view of water management issues and water quality resources," said Paul Schwartz, national policy coordinator for the citizen advocacy group Clean Water Action.

Outdated Paradigms

Participants agreed that the research and regulatory communities are operating with old ways of thinking about water supply, management, and policy. Societal changes such as the migration of people out of urban centers are driving development patterns that create new public health risks in areas where planning or authority may be insufficient, said Douglas Hall, manager of watershed initiatives at Ohio's Miami Conservancy District, a political subdivision formed to address water concerns. For example, the proliferation of individual septic systems in expanding outer suburbs presents unchecked new risks, such as overflowing into wells or contaminating groundwater. Comprehensive land use planning must address sustainability of water resources, Hall said, and public health risks associated with the development patterns of the last three decades must be better understood.

New scientific methods for studying health risks in the population, advanced monitoring, and analysis are also needed to protect the water supply. Currently, 80% of U.S. waterborne disease outbreaks go uncharacterized, Griffiths said. "We don't know the sources of them."

Water treatment approaches also need updating to keep in step with emerging microbial threats such as hepatitis E virus. "Conventional treatment did the trick in 1910, but it doesn't do the trick right now," Griffiths said. Not only does conventional water treatment not remove all risk of pathogen transmission, but 99% removal or inactivation is not good enough for some threats, for which the remaining 1% can still cause health problems. Although there are technologies that can remove or inactivate 100% of contaminants in water, such technologies are costly or impractical for now, Griffiths said. He believes developing inclusive technologies--for example, methods to kill everything in the water that contains nucleic acids--are the way to go.

Moreover, existing models are not good at water quality forecasting, said Ken Reckhow, director of the Water Resources Research Institute of the University of North Carolina. Scientists currently don't have the data or tools necessary to test with any reasonable level of reliability how land use control or restrictions or watershed activities affect concentrations of water contaminants.

Policy and the People

Setting clear research priorities is another thorny problem. Many critical research questions remain to be answered, such as at what level concentrations of different compounds present an unreasonable health risk. "I'm not sure we actually know which stressors are more important. And trying to decide where to put our research dollars is one of the more difficult issues that we have," said Cynthia Dougherty, director the Environmental Protection Agency Office of Ground Water and Drinking Water.

But in the end, successfully communicating research results may be the most important factor in changing water use behaviors and conservation practices. "The science has to be understood and put into action by average people as well as the experts. We need to see the public as a vital resource and force for positive change," said Susan Seacrest, president of The Groundwater Foundation, an education and advocacy group. Even if the public is reluctant to accept such radical notions as drinking recycled wastewater, they need to start appreciating that, over time, water really is not an unlimited resource. Said James Crook, a Boston water reuse consultant, "Water is greatly undervalued and subsequently underpriced as to what it's worth overall."