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Geography

Mexico forms part of the northern American Continent, including Canada and the United States of America. Mexico is a country bordering the Caribbean Sea and the Gulf of Mexico, between Belize and the United States and bordering the North Pacific Ocean. The total area of the country is 1,964,375 Sq.Km., of which 1,959,248 is continental surface and 5,127 Sq.Km. on the islands. It is the fourteenth largest country in the world. With coast lines of 9,330 Km, the land border is 4,389 Km with three different countries: Belize 193 Km, Guatemala 956 Km and USA 3,152 Km. The terrain comprise high, rugged mountains; low coastal Plains; high plateaus; and desert.

Population and land use

Mexico’s population is approximately 130 Million as per Population reference Bureau (2019). Most of the population is found in the middle of the country between the states of Jalisco and Veracruz; approximately a quarter of the population lives in and around Mexico City, the national capital. The rural population involved in agricultural activities has been estimated at 9.7 Million of which 33% owned land, the 9% were landless producers and the 58% workers. Out of the nearly 196 Mha of the country’s total area, around 27 Mha are covered mainly by pastures, 88 Mha sustain low bushes, 53 Mha are covered by forests or tropical woods, and 7 Mha correspond to deserts, urban areas and water bodies. The country has a very wide range of vegetation zones; from places where there is almost no vegetation, as is the case in the most arid deserts and in permanently snow covered areas, to regions such as the Lacandon rain forest in the state of Chiapas.

Climate and rainfall

Mexico has an annual average rainfall of around 800 mm, concentrated mainly in three months, from July to September. The spatial distribution of rainfall and temperatures produce a great variety of climates, that range from arid (31%) and semi-arid (36%) conditions in the northern region where the largest irrigation systems are located, to the humid tropic (33%) in the southeast. Nearly 27% of the rainfall, that is 410 BCM, converts into superficial runoff that feeds 13 main rivers of the nation. Rainfall is highly variable and droughts are frequent. The states most affected by drought, as measured by the agricultural area affected, are Chihuahua, Mexico and Zacatecas. The uneven rainfall distributions, in space and time, compelled government and private enterprises to develop water infrastructure, in order to regulate water availability.

Food and agriculture

Mexico, a classified arid and semi-arid country, has some 21 Mha area as arable land. The agricultural sector plays an important role in the economic development of the country accounting for 8.4% of gross domestic product (GDP) and employing 23% of the economically active population. By far the six most important crops grown in Mexico are corn, bean, wheat, sugarcane, coffee and sorghum. The first two are staples of the traditional diet, with the result that approximately half of the land in cultivation is dedicated to corn and bean. Coffee is the main export product and sorghum is used for feed in the rapidly growing poultry and pork industries. Main factors that have influenced the limited performance of the agriculture sector include land degradation, policy-deficit issues, unfavorable urban-rural pricing, limited application of technology and scientific advances, and limited or declining financing in the sector among others

Irrigation and drainage

Of the 7.3 Mha with irrigation facilities in Mexico, about 3.3 Mha correspond to 86 bigger systems, namely irrigation districts (ID). The remaining 4.0 Mha are distributed among more than 50 thousand small size irrigation units. Approximately 4.3 Mha are irrigated with surface waters, and the remaining, some 3 Mha are served by groundwater pumping. The most important irrigation districts in Mexico are: Culiacán-Humaya, San Lorenzo, Yaqui River, Fuerte River, Colorado River, Bravo River, Higher Lerma River, Lagunera Region, Guasave, Mayo River, Lazaro Cardenas, and Delicias. Only 20 IDs are greater than 50,000 ha but represent almost the 2/3 of national command area in Irrigation districts. Irrigated agriculture contributes about 55% of the total value of agricultural production and accounts for about 70% of agriculture exports. Mexico’s government initiated a number of structural reforms in the water sector aimed to introduce modern water management in irrigation. The average irrigated plot size is from 3 to 9 ha in irrigation districts and about 2.6 ha in irrigation units.

Water resources management

Water is abundant in the relatively sparsely populated South and scarce in the more densely populated Center and North of the country. The Center and the North of the country where 77% of Mexico’s population lives and 85% of its GDP is generated dispose of only 32% of the country’ s renewable water resources. Total internal renewable water resources are estimated at 457 BCM per year, plus 49 BCM/year inflows from neighboring countries (average 1977-2001). The largest river on the Pacific coast is the Balsas River (24 BCM/year) and the largest river on the Atlantic Coast is the Grijalva–Usumacinta flowing from Guatemala to Mexico (115 BCM/year). The Rio Bravo is the longest river (2,018 Km), called Rio Grande in the United States, and also the river with the largest basin (226,000 Km²), half in the United States and half in Mexico. The renewable volume of groundwater is estimated at 31 BCM and non-renewable supplies, stored in aquifers, amount to 100 BCM.

Water policy

The economic crisis of the 1980’s led to drastic changes in Mexico’s irrigation policy. Under the National Program (1989–1994) for Decentralization of Irrigation Districts, derived from the National Development Plan, Mexican government initiated the management transfer of irrigation districts to Water User Civil Associations (WUCA’s). The National Program, implemented by the National Water Commission (Comisión Nacional del Agua, CONAGUA), originally planned the transfer of operation and maintenance of 21 irrigation districts, comprising 1.98 Mha. To date, actual targets far exceed the  1990-1994 area goal. Mexican irrigation zones have been institutionally divided in two broad types: irrigation units (IUs) and irrigation districts (IDs). The irrigation districts, covering 3.3 Mha (or 45% of the irrigated area) are large-scale irrigation schemes supplied mainly with surface water and some with groundwater. The responsibility for their operation and maintenance has been transferred to WUCA’s in the 1990’s, except for 1% of the area that is still operated by CONAGUA as well as some main hydraulics works such as dams and large canals. The irrigation units, covering about 4.0 Mha (or 55% of the irrigated area), are smaller irrigation schemes, supplied from both surface and groundwater and operated and maintained from their inception by agricultural producers. The transfer of the biggest irrigation systems or irrigation districts (45% of total irrigated area) from federal government to water users’ associations (WUCA’s) is a key component of the current water policy.

ICID and National Committee

Mexico joined ICID in the year 1951 and established the Mexican National Committee of ICID (MXCID) and has been actively participating in the events of ICID. MXCID has successfully organized: the 7^th ICID Congress and 20^th IEC meeting at Mexico City, in 1969; 3^rd Pan American Conference (PAC-3) at Mazatlán, in 1992; and PAC-4, Yucatan, in 2000; 5^th Pan American Regional Conference in 2006 and the 23^rd ICID Congress and 68^th IEC during 8-14 October 2017at Mexico City. Three of the members of MXCID have been the Vice Presidents of ICID in the past: Mr. Abelardo Amaya Brondo (19711974), Mr. Alberto Barnetche González (1964-1967), and Ing. Manuel Contijoch Escontria (2001-2004).  Dr. (Ms) Blanca E. Jimenez-Cisneros is General Director of the National Water Commision and can be contacted at