MEXICO CITY'S WATER SUPPLY

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the board responsible for the report were chosen for their special competencies and with regard for appropriate balance.

This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

Support for this project was provided by the Ford Foundation under Agreement No. 910-1413, the Tinker Foundation, the U.S. Environmental Protection Agency under Agreement No. CX-820728-01-0, the Mexico National Science and Technology Council (CONACYT), the Mexico Ministry of Health, the United Nations Development Program, the National Research Council Fund, the Rockefeller Foundation, and the MacArthur Foundation.

About the Cover: Paisaje by Emilio Rosenblueth, oil on canvas, 1938; collection of the Rosenblueth family. Use of this painting is in memory of Emilio Rosenblueth, Jr. (1926-1994), son of the artist, who did much for the advancement of science in Mexico and was so instrumental in building bridges to the scientific community in the United States. Dr. Rosenblueth, Jr. was director of the Institute of Engineering of the National University of Mexico (UNAM), the dean of science for the university, president of the Academy of Science (AIC), vice-minister of the Ministry of Education, and foreign associate member of NAS and NAE. Special thanks to Sra. Alicia Laguette de Rosenblueth, wife and companion of Emilio, and his family for permission to reprint.

Library of Congress Catalog Card No. 95-67404

International Standard Book Number 0-309-05245-9

Additional copies of this report are available from:

Copyright 1995 by the National Academy of Sciences. All rights reserved.

Printed in the United States of America

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The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce Alberts and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council.

The Mexico Academy of Science (Academia de la Investigación Científica, A.C.) was created in 1959 and is dedicated to organizing and promoting scientific investigations in all aspects of science. Dr. Mauricio Fortes is president of the Mexico Academy of Science.

The Mexico National Academy of Engineering (Academia Nacional de Ingeniería, A.C.) was created in 1974 to promote high quality engineering research, education, and technological development. Dr. Héctor Nava is the president of the Mexico National Academy of Engineering

COMMITTEE ON THE MEXICO CITY WATER SUPPLY

CHARLES T. DuMARS, co-Chair, University of New Mexico, Albuquerque

ISMAEL HERRERA-REVILLA, co-Chair, Academia Nacional de Ingeniería, A.C., and Instituto de Geofísica, UNAM, México. D.F.

IRINA CECH, University of Texas, Houston

RANDALL CRANE, University of California, Irvine

CRISTINA CORTINAS-DE NAVA, Instituto Nacional de Ecología de la Secretaría de Desarrollo Social, México, D.F.

JOSE RAMÓN COSSÍO-DÍAZ, Suprema Corte de Justicia de la Nación, México, D.F.

RICHARD S. ENGELBRECHT, University of Illinois at Urbana-Champaign

ROBERT N. FARVOLDEN, University of Waterloo, Canada, and National Ground Water Association, Dublin, Ohio

HELEN INGRAM, University of Arizona, Tucson

JESUS KUMATE-RODRÍGUEZ, Secretaría de Salud, México, D.F.

LUCRECIA LOZANO-GARCÍA, Instituto Tecnológico y de Estudios Superiores de Monterey, Nuevo León, México

JUAN MANUEL MARTINEZ-GARCÍA, Dirección General de Construcción y Operación Hidráulica del Departamento del Distrito Federal, México, D.F.

RUBÉN MARTÍNEZ-GUERRA, Comisión Nacional del Agua, México, D.F.

CARLOS VÉLEZ-OCÓN, Instituto Nacional de Investigaciones Nucleares, México, D.F.

DAVID WILK-GRABER, Consultor en desarrollo urbano y medio ambiente, México, D.F.

WSTB LIAISON

KENNETH D. FREDERICK, Resources for the Future, Washington, D.C.

STAFF FOR THE COMMITTEE

GARY D. KRAUSS, Study Director, Water Science and Technology Board, National Research Council

JULIA MELCHOR-SÁNCHEZ, Study Director, Fundación Ricardo Monges López, A.C.

ALEJANDRO LOZANO-GUZMÁN., Study Director, Academia Nacional de Ingeniería, A.C.

GREGORY NYCE, Project Assistant, Water Science and Technology Board, National Research Council

WATER SCIENCE AND TECHNOLOGY BOARD

DAVID L. FREYBERG, Chair, Stanford University, California

BRUCE E. RITTMANN, Vice Chair, Northwestern University, Evanston, Illinois

LINDA M. ABRIOLA, University of Michigan, Ann Arbor

J. DAN ALLEN, Chevron USA, Inc., New Orleans, Louisiana

PATRICK L. BREZONIK, University of Minnesota, St. Paul

WILLIAM M. EICHBAUM, The World Wildlife Fund, Washington, D.C.

WILFORD R. GARDNER, University of California, Berkeley

WILLIAM L. GRAF, Arizona State University, Tempe

THOMAS M. HELLMAN, Bristol-Myers Squibb Company, New York, New York

CHARLES C. JOHNSON, U.S. Public Health Service (Retired), Washington, D.C.

CAROL A. JOHNSTON, University of Minnesota, Duluth

WILLIAM M. LEWIS, JR., University of Colorado, Boulder

CAROLYN H. OLSEN, Brown and Caldwell, Pleasant Hill, California

CHARLES R. O'MELIA, John Hopkins University, Baltimore, Maryland

IGNACIO RODRIGUEZ-ITURBE, Texas A&M University, College Station

HENRY VAUX, JR., University of California, Riverside

Staff

STEPHEN D. PARKER, Director

SHEILA D. DAVID, Senior Staff Officer

CHRIS ELFRING, Senior Staff Officer

JACQUELINE MACDONALD, Senior Staff Officer

GARY D. KRAUSS, Staff Officer

ETAN GUMERMAN, Research Associate

JEANNE AQUILINO, Administrative Associate

ANITA A. HALL, Administrative Assistant

ANGELA BRUBAKER, Senior Project Assistant

MARY BETH MORRIS, Senior Project Assistant

GREGORY NYCE, Senior Project Assistant

COMMISSION ON GEOSCIENCES, ENVIRONMENT, AND RESOURCES

M. GORDON WOLMAN (Chairman), The Johns Hopkins University, Baltimore, Maryland

PATRICK R. ATKINS, Aluminum Company of America, Pittsburgh, Pennsylvania

EDITH BROWN WEISS, Georgetown University Law Center, Washington, D.C.

JAMES P. BRUCE, Canadian Climate Program Board, Ottawa, Ontario, Canada

WILLIAM L. FISHER, University of Texas, Austin

EDWARD A. FRIEMAN, Scripps Institution of Oceanography, La Jolla, California

GEORGE M. HORNBERGER, University of Virginia, Charlottesville

W. BARCLAY KAMB, California Institute of Technology, Pasadena

PERRY L. MCCARTY, Stanford University, California

S. GEORGE PHILANDER, Princeton University, New Jersey

RAYMOND A. PRICE, Queen's University at Kingston, Ontario, Canada

THOMAS A. SCHELLING, University of Maryland, College Park

ELLEN SILBERGELD, Environmental Defense Fund, Washington, D.C.

STEVEN M. STANLEY, The Johns Hopkins University, Baltimore, Maryland

VICTORIA J. TSCHINKEL, Landers and Parsons, Tallahassee, Florida

Staff

STEPHEN RATTIEN, Executive Director

STEPHEN D. PARKER, Associate Executive Director

MORGAN GOPNIK, Assistant Executive Director

JEANETTE SPOON, Administrative Officer

SANDI FITZPATRICK, Administrative Associate

ACADEMIA DE LA INVESTIGACION CIENTIFICA, A.C.

MAURICIO FORTES-BESPROSVANI, President

JUAN RAMON DE LA FUENTE-RAMIREZ, Vice President

LINDA MANZANILLA-NAIM, Secretary-Elect

RUBEN BARRERA-PEREZ, Secretary

SAUL VILLA-TREVIÑO, Treasurer

ACADEMIA NACIONAL DE INGENIERIA, A.C.

HECTOR NAVA-JAIMES, President

LUIS ESTEVA-MARABOTO, Vice President

CRISTINA VERDE-RODARTE, Secretary

OCTAVIO MANERO-BRITO, Treasurer