In This Issue
Winter Issue of The Bridge on Sustainable Water Resources
December 15, 2011 Volume 41 Issue 4

Protecting Our Most Precious Natural Resource

Thursday, December 15, 2011

Author: Stephen D. Parker

Editor’s Note

Global challenges related to water, a precious and limited resource, will become increasingly difficult over the coming decades. These challenges encompass: providing adequate amounts of clean water; controlling polluted runoff and groundwater; maintaining healthy hydro-ecosystems; managing the risks of floods and droughts; addressing competition for water among users; and maintaining aging water infrastructure, to name just a few.

The articles in this issue of The Bridge are based on presentations at a convocation of professional engineering societies hosted by the National Academy of Engineering (NAE) in Washington, D.C., on May 16, 2011. Approximately 100 leading engineers from industry, academia, and government, representing about 25 engineering societies, participated in a special session on water, a topic they had identified as critical to the nation and to engineering.

In opening remarks, NAE President Charles Vest reminded us that NAE had twice before identified water issues as a “grand challenge” for the future, not only for the United States but for the world. Indeed, The Bridge has previously featured a variety of water science and technology topics in “special issues” (most recently in fall 2008).

The availability and quality of water are greatly impacted by changes in land use and climate. Water is essential to life, as well as to economic productivity, and how its quantity and quality are managed affects the world population in many ways. Indeed, water resources and human activities are inextricably linked.

In organizing the convocation and preparing this issue of The Bridge, I turned to friends in the National Research Council (NRC) Water Science and Technology Board ( network to address topics of current and societal relevance. We did not attempt to be all-inclusive, nor did we focus on narrow technical topics. Instead, we selected topics that are interesting, complex, current, and require or reflect collaboration among engineers and physical, life, and social scientists.

The first article is by my colleague at the NRC, Jeffrey Jacobs, a geographer and water policy expert, who writes about water management in the Colorado River basin. Water from the Colorado, which is distributed throughout the southwestern United States, is critical to supporting life, the economy, and aquatic ecosystems throughout the region. Jeff’s article covers a broad range of topics, from the significance of the latest developments in paleo-hydrologic science to water conservation. As he observes, even though the long-term availability of Colorado River water is limited and likely to decrease in the future, the region is concurrently experiencing rapid population growth and increased water demand.

Jeff’s paper is followed by a contribution from NAE member David Dzombak, an environmental engineer whose research at Carnegie Mellon University is focused on water quality. Dave describes the challenges of understanding and controlling chemical nutrients, principally nitrogen and phosphorus, in our aquatic systems. He also discusses diffuse, “nonpoint” pollution, perhaps the nation’s principal water quality challenge. His focus is on the impacts of, and efforts to control, nutrient inputs to the Chesapeake Bay and northern Gulf of Mexico.

Next, Professor Rutherford Platt, Emeritus Professor of Geography at the University of Massachusetts, Amherst, summarizes pathbreaking efforts, from 1840 to the present, by New York City and Metropolitan Boston to (1) develop large-scale hinterland, gravity-flow water sources; (2) reduce per capita demand since the 1980s to stay within the safe yields of existing water sources; and (3) implement a variety of nonstructural watershed-management measures to qualify for “filtration avoidance determinations” issued by the U.S. Environmental Protection Administration under the Safe Drinking Water Act.

Mohammad Habibian, an environmental engineer at the Washington Suburban Sanitary Commission (WSSC), focuses on the challenges facing large urban water and wastewater utilities. WSSC is a progressive, not-for-profit utility that serves 1.8 million customers in the two Maryland counties adjacent to the District of Columbia. Habibian describes critical challenges at every step of the water-wastewater cycle from the perspectives of industry and sustainability. He covers source water quantity and quality, regulatory and treatment issues, contaminants of emerging concern, infrastructure maintenance, funding, communication in this era of social networking, and the need for collective wisdom and cooperation in addressing water issues.

To wrap up, NAE member Gerald Galloway, an engineer, geographer, and water policy expert at the University of Maryland, addresses a potpourri of water policy challenges facing the nation. He points out that climate change, on top of population growth and the growing need for infrastructure renewal and new development, will increase the stress on our water resources. He argues for national approaches to water governance and decries the absence of comprehensive national water policies that could enable integrated management of water resources. Gerry calls on the water community to embark on a campaign to improve communication with decision makers on all levels.

Taken together, the articles in this issue reinforce ideas that have been evident to water resource professionals for at least a decade. First, water resource challenges are directly proportional to population growth, changes in land use, and climate change. The challenges are most apparent in areas where competition for water resources is greatest.

Second, even though the most pressing water issues vary widely with local conditions, an increasing number of regions in the United States are confronted with critical issues that must be addressed to ensure the future well-being of our people and our environment.

Finally, no area in the United States is likely to face a sudden water crisis. Instead, crises will result from the accumulation of water resource problems that have been insufficiently dealt with over time. Lessons learned in one region about managing these problems will be increasingly useful to other regions as they strive to anticipate and respond to water problems before they become catastrophes.

About the Author:Stephen D. Parker is senior director of the Water Science and Technology Board of the National Research Council.