South America | Dam legacy
Humberto Marengo Mogollón, President of the Mexican Committee of ICOLD, gives an historical insight into his sector of the dams industry, and offers a warm welcome to ICOLD 26 as Mexico plays host for the 94th Annual Meeting.
Above: The Malpaso Dam, officially known as the Nezahualcóyotl Dam, is located in the Centro region of Chiapas, Mexico
Below: The La Yesca Dam is located on the Santiago River between Nayarit and Jalisco, Mexico
THE HISTORY OF DAMS in Mexico dates back to pre- Hispanic times. One of the earliest known hydraulic works is the Purrón Dam, located in the Tehuacán Valley in the state of Puebla, built roughly between 750 and 500 BCE. This structure, made primarily of earth and stone, was designed to capture seasonal runoff and support early agricultural irrigation systems in an arid region. In the modern era, dam development accelerated in the early twentieth century with projects such as the Necaxa hydroelectric system in Puebla, completed around 1905, which became the first major hydropower scheme supplying electricity to Mexico City. Throughout the mid-twentieth century, Mexico experienced significant expansion
in dam construction, particularly large multipurpose reservoirs for irrigation, flood control, water supply, and hydroelectric generation, including major projects on rivers such as the Grijalva, Balsas and Santiago. Mexico has a large and diverse dam infrastructure.
The National Water Commission’s (Conagua) inventories indicate that the country has over 6687 dams and reservoirs distributed across its river basins, and according to ICOLD criteria there are 1026 large dams. The majority of these structures were built during the twentieth century to support irrigation and water supply programmes, particularly in semi-arid agricultural regions in the north of Mexico. In terms of structural typology, the most common dams are embankment dams, including earthfill and rockfill dams, which represent more than half of the national inventory. Concrete and masonry gravity dams form another important group, particularly in hydropower projects and water supply. Other types such as arch dams exist but are less common. Many reservoirs are multipurpose and support combinations of irrigation, flood control, municipal water supply, and hydroelectric generation.
Recent challenges In recent years, several challenges have become
increasingly important for Mexico’s dam sector. One major issue is hydroclimatic variability and prolonged drought, which has placed pressure on reservoir systems and water supply reliability in different regions of the country. Sedimentation is another widespread concern because it gradually reduces storage capacity,
18 | April 2026 |
www.waterpowermagazine.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45
