Lerma River - Importance in Mexico

Importance in Mexico

During the 17th and 18th centuries, large haciendas were established along this river, including the Atenco ranch, which was founded with bulls that belonged to Hernán Cortés. The bulls from this area are considered some of the finest stock for bullfighting. The river is dotted with cities such as Lerma, México and San Mateo Atenco to small picturesque villages with cultural significance such as Malinalco.

The Lerma River–Lake Chapala basin is considered to be the most important watershed in the country by the federal government. With its major tributaries, the Laja, Apaseo, and Turbio the Lerma constitutes Mexico's largest river system. The Lerma River is not navigable by water craft, but it is critical to regional agricultural irrigation. In the Lerma River/Lake Chapala watershed, 52,125 of the total 78,000 (roughly 67%) farmers are classified as small farmers. Currently 820,000 hectares are irrigated and an estimated three million hectares are in agricultural production.

The population in the watershed as of 1997 was 9.35 million with an annual growth rate slightly less than the national average. The population is distributed among 6,224 localities; 18 of these have a population greater than 50,000 inhabitants. The rural population is currently 32 per cent. The Lerma's water is also a source for the municipal water supply in the Guadalajara and Toluca metropolitan areas. While water extraction and use has been adequate for the region's larger population centers, rural areas have had chronic problems with access to potable water from the river and the aquifers that feed it. Wells drilled into these aquifers have very low yields.