enhanced interest in concepts with names such as “smart growth” and “sustainable resource management”—basically, an approach to developing urban and urbanizing areas in ways that minimize their effects on the environment in general and on receiving waters in particular.

Agricultural practices, meanwhile, have increasingly become a focus of attention at the U.S. Environmental Protection Agency (EPA) and other agencies. To some extent, we have brought certain agricultural operations—in particular, combined animal feeding operations (CAFOs)—under the umbrella of our point source regulatory management program. However, many other agricultural practices that constitute nonpoint sources remain relatively unregulated from the federal perspective. EPA is working with the U.S. Department of Agriculture, which has considerable resources in this area, to improve agricultural practices so as to minimize the nutrient loadings and the sediment and pesticide runoff that can result from agricultural operations.

  • Emerging contaminants. Recent studies by the U.S. Geological Survey have found that new contaminants and contaminant mixtures, such as pharmaceuticals, detergent metabolites, and natural and synthetic hormones, are appearing in our surface waters. To some degree, as our technology for detection and monitoring improves, we are finding things that perhaps have always been there, or have been there for a while, but are just now coming to our attention. In other cases, contaminants are emerging because of changes in land-use patterns, for example, or drug technology. We are only now beginning to focus attention on the significance of these findings, their implications for research, and the management issues they may ultimately pose for drinking water quality.

  • Aging infrastructure. There is growing concern about an imminent crisis regarding the physical infrastructure of our water supply and wastewater management systems. Various estimates identify enormous gaps between current levels of expenditure to replace and upgrade that infrastructure and the amount needed simply to address issues of growth, deterioration because of age and wear, and heightened environmental standards. Depending on the study, the necessary investments could total hundreds of billions, if not trillions, of dollars.

  • Pathogens. High concentrations of humans and of farm animals, nonpoint source runoff, greater numbers of onsite septic systems resulting from suburban growth patterns, and preexisting combined sewer systems in older urban areas all continue to inject pathogens into our source waters and pose challenges to the safety of our drinking water. Multiple



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