The Lining of the All American Canal: Effects on Mexico Construction of the All-American Canal, 1935 (top), 1939 (bottom), José Luis Castro-Ruiz and Vicente Sánchez- and 1936 (background). Courtesy of Munguía – El Colegio de la Frontera Norte U.S. Bureau of Reclamation.

n 1988, the U.S. Congress approved 7.3 million acre-feet (maf) annually in Law 100-675, authorizing the equal parts, creating high expectations for Secretary of the Interior to line the the economic transformation of the region. All-American Canal (AAC) along a I The Alamo Canal experienced a number 23-mile section in the southern of . Lining the canal was of difficulties in the years that followed. expected to save an estimated 70,000 acre- An inability to control canal volumes from feet of water per year lost to seepage the resulted in a series where the canal traverses sand dunes. The of floods from 1905 to 1907, affecting Mexican government quickly filed an the cities of and Calexico and informal complaint through the Mexican agricultural areas on both sides of the section of the International Boundary and border, and creating the . These Water Commission (IBWC), claiming conditions, together with the dependence potential harm to water users in the of the canal operation on Mexican Most evident is a potential decrease in Mexicali Valley, and noting that the United policy changes, moved Imperial Valley static levels of the Mexicali Aquifer, States was legally obligated by Minute 242 users to lobby for their own access to which depends mostly on AAC seepage to notify Mexico of any changes affecting the Colorado. Once created in 1911, the for recharge in areas near the canal groundwater along the border. The canal IID began to advocate building an “All- (Herrera et al., 2004). It is estimated that was never lined, but the international American Canal” north of the international the aquifer would be short 67,000 acre-feet controversy was recently revived, sparked border. These efforts paid off with passage of water per year if the AAC were lined. by a 2002 agreement between California’s of the Boulder Canyon Project Act in The impacts of this would be significant, Department of Water Resources and 1928, which included construction of given the importance of groundwater to the Imperial Irrigation District (IID) to the . The AAC was built in agricultural production in the Mexicali guarantee $126 million to build and line the 1930s, becoming the main source of Valley. Additionally, groundwater salinity a 23-mile canal parallel to the AAC. water for the Imperial Valley by 1942. is expected to increase if the canal is lined, as seepage from the AAC contributes The AAC now delivers approximately Origins of the All-American Canal significantly to lower the concentration of 3.1 maf of Colorado River water annually The history of the AAC is rooted in suspended solids in the aquifer (Herrera to nine cities and 500,000 acres of the quest for water spurred by the et al., 2004; García-Saillé et al., 2004). agricultural fields in Imperial Valley (see agricultural development of the Imperial The higher salinity is likely to affect the cover image). It extends southwest 82 and Mexicali valleys in the early 20th productivity of less salt-tolerant crops. miles from the Imperial Dam to a point century. The California Development just 10 miles west of Calexico. Most of Company, founded in 1896, undertook Other economic and social effects of its path runs close to the international the first project to supply the area with potential water quality deterioration border with Mexico, particularly through water from the Colorado River. Technical must be considered. For instance, the sand dunes near Pilot Knob, where problems associated with transporting 1,010 families that reside in areas water through U.S. territory resulted in the the border is only 500 feet away. identified as most directly dependent on use of a binational channel in the Mexicali AAC seepage rely on the water from Valley—the Alamo Canal—operated Groundwater, Social, and the aquifer for domestic uses. In the by a Mexican subsidiary, Sociedad de Environmental Impacts absence of any mitigation measures, Terrenos e Irrigación de . Studies by Mexican researchers have these groups will eventually seek Beginning in 1901, the operation of the identified a number of impacts that lining relocation in Mexicali’s urban area. This Alamo Canal provided both valleys with the canal would have on Mexican areas. migration could cause water providers 26 • September/October 2005 • Southwest Hydrology in Mexicali to accelerate their reliance Several examples of shared interest and resumed talks on the issue, reconsidering on water reserves, which incidentally successful binational cooperation already potential negative impacts on the Mexican are based on groundwater allotments. exist which could serve as models. side and discussing ways to either mitigate The Lining of the Governments and communities on both those effects or compensate for the losses. Environmental effects of the lining sides of the border are working jointly This is surely a more promising approach project on Mexican sections close to to save the Lower Colorado Delta and for the future, with sustainable management All American Canal: the AAC are also often overlooked. preserve its biodiversity. Additional of resources as our mutual goal. While the environmental impact study cooperation has occurred with the Rio conducted by the Sonoran Institute (2005) Contact José Luis Castro-Ruíz at [email protected] Effects on Mexico Nuevo restoration in the Mexicali area, the and Vicente Sánchez-Munguía at [email protected]. emphasizes the loss of wetlands formed construction of a binational aqueduct on by AAC seepage on the U.S. side—about Mexican territory to transport Colorado 1,570 acres—an important wetlands River water to San Diego and Tijuana, References...... system more than three times that size García-Saillé, G., A. López, and J.A. Navarro, and a new international agreement to 2004. El impacto del revestimiento del canal has evolved in the Mexican zone known build a secondary wastewater treatment “Todo Americano” sobre la calidad del agua as the Mesa de Andrade. In all, at least facility in Tijuana to solve water del acuífero y el rendimiento de los cultivos del Valle de Mexicali, in El Revestimiento 100 bird species reside there, including contamination problems in the area. del Canal Todo Americano: ¿Competencia several under federal protection in the o Cooperación por el Agua en la Frontera United States and Mexico. These wetlands México-E.U.?, V. Sánchez-Munguía (coord.). A Final Word Mexico City: Plaza y Valdéz, pp.77-106. serve also as a migratory rest area for The decision to build a parallel lined Herrera, J., M. Norzagaray, G. García-Saillé, A. more than 10,000 birds each year. channel originated from concerns over Cortéz, and D. Jorquera, 2004. Fluctuaciones en la calidad del nivel freático del agua urban water needs in Southern California. subterránea en las proximidades al Canal Mexico’s Two Alternatives A binational conflict arose in the process, Todo Americano, porción mexicana, in El Revestimiento del Canal, pp.57-76. Although the issue is complex, Mexico due to negative impacts on the Mexican Sonoran Institute/Pronatura, 2005. Diagnóstico and the United States could still reach side and the one-sided nature of the action, general del proyecto de revestimiento del Canal an agreement on lining the AAC. One which violated the precepts established by Todo Americano. Environmental Impact Study option calls for Mexico to appeal to of the All-American Canal undertaken for Minute 242. This polarization has been Dirección General de Ecología del Gobierno the international courts to consider aggravated by the complexity of the issue de Baja California (report on CD-ROM). the issue an international rather than a and lack of negotiation. However, recent domestic matter. However, binational examples of environmental cooperation cooperation seems to offer the best hope, between Mexico and the United States provided both parties are motivated to demonstrate that mutually satisfying share information and work together solutions are possible when competition to manage the water resources rather and unilateral action give way to than compete for their appropriation. cooperation. Both countries have recently

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