Zona Protectora Forestal Vedada Cuenca Hidrográfica del Río Necaxa: Mapped Protected Geography

The history of the Zona Protectora Forestal Vedada Cuenca Hidrográfica del Río Necaxa is closely tied to the development of hydroelectric power in central Mexico. The river's potential was recognized in the late nineteenth century, with major dam construction projects beginning around 1890. Over the following decades, a system of reservoirs was built across the Necaxa basin and its tributaries, including the Necaxa, El Tejocotal, Los Reyes, Nexapa, and Tenango dams, collectively storing large volumes of water for power generation.

On 20 October 1938, President Lázaro Cárdenas signed a decree establishing the Necaxa river basin in Hidalgo and Puebla as a protected forest zone. The decree aimed to preserve the basin's forests and microclimate, prevent soil erosion, regulate the rivers' flow, and ensure the long-term security of hydroelectric production. This made the Necaxa basin one of the earliest modern forest protection initiatives in Mexico, predating the country's broader environmental legislation.

In 2002, the Mexican government updated the area's designation, reclassifying it as a natural resources protection area with a more comprehensive conservation mandate. Then, on 2 February 2008, the five reservoirs within the basin were formally designated a Ramsar Wetland of International Importance, recognizing the basin's ecological and hydrological significance at a global scale.

The protected area occupies a dramatic section of the Sierra Madre Oriental, where the Necaxa River and its tributaries descend through high, forested mountains. The watershed is characterized by steep ridges, narrow canyons, and abrupt elevations that have shaped both the river's course and human use of the area. The river, which begins south of Huauchinango under the name Totolapa, drops into the deep ravines of the Sierra Norte de Puebla, producing waterfalls known as Salto Chico and Salto Grande.

Within these mountains, the landscape includes a network of artificial reservoirs created by the Necaxa hydroelectric system. These reservoirs interrupt the flow of the river, creating broad stretches of standing water surrounded by forested slopes. The combination of natural canyons, forested mountains, and engineered reservoirs gives the protected area a varied and visually striking profile, dominated by forested slopes rather than open peaks or plains.

The vegetation of the basin reflects the altitudinal and climatic gradients of the Sierra Madre Oriental. Lower montane forests, mid-elevation pine-oak stands, and humid cloud forest communities all contribute to the area's plant diversity. The watersheds are heavily forested, which is the very reason the area was originally protected: dense tree cover stabilizes the steep slopes, regulates runoff, filters water, and sustains the rivers that feed the reservoir system.

The Mexican tree fern Cyathea mexicana, an endangered species, occurs here, indicating the presence of humid and shaded microhabitats characteristic of cloud forest transitions. Aquatic and wetland habitats add a parallel ecological layer, with reservoir margins, inflowing streams, and riparian corridors supporting distinctive plant communities adapted to fluctuating water levels.

The Necaxa basin is of particular importance for waterbirds, especially around the reservoirs and along the river corridors. The reservoir system is home to great egrets, snowy egrets, little blue herons, neotropic cormorants, ringed kingfishers, and green kingfishers, making the area a notable inland waterbird habitat in central Mexico. The combination of forested shore margins and open water provides feeding, resting, and nesting conditions for these species.

Among amphibians, the Puebla frog (Lithobates pueblae), an endangered species, inhabits the river and its basin. The continued presence of such range-restricted species underscores the role of protected forests and clean flowing water in supporting freshwater biodiversity. While the area is not primarily known for large mammals, the forested terrain provides habitat for typical Sierra Madre Oriental fauna, supporting regional ecological connectivity.

The conservation significance of this protected area lies in its role as a forested headwater landscape that secures water quantity and quality for a substantial part of central Mexico. Originally established to protect watershed function for hydroelectric generation, it has evolved into a broader conservation zone that recognizes forests, rivers, and reservoirs as a single integrated ecosystem. Maintaining forest cover on the steep slopes directly controls erosion and sedimentation in the reservoirs, which is essential to the long-term viability of the hydroelectric system.

The 2008 Ramsar designation of the reservoirs as a wetland of international importance gave the basin additional international visibility, acknowledging its importance for migratory and resident waterbirds and for wetland-dependent biodiversity. Today, the protected area is administered under the National Commission of Natural Protected Areas, and its conservation strategy links forest protection, sustainable resource use, biodiversity preservation, and energy infrastructure in one management framework.

The Necaxa basin lies within the cultural landscape of the Sierra Norte de Puebla, a region historically inhabited by Nahua communities and characterized by deep connections to mountain watercourses. The rivers and waterfalls of the basin, including the famed Salto Chico and Salto Grande, are part of local identity and traditional knowledge, even though the modern reserve is primarily defined by its environmental and energy-related functions.

The hydroelectric development of the late nineteenth and twentieth centuries transformed the region economically and demographically, linking a remote mountain zone to the broader industrial and urban development of central Mexico. Today, the basins, dams, and forests form a shared regional heritage that blends indigenous landscape traditions with modern infrastructure and conservation policy.

A protected mountain watershed at the headwaters of the Necaxa River, surrounded by steep canyons of the Sierra Madre Oriental.

Home to a chain of five hydroelectric reservoirs that are both engineering landmarks and internationally recognized wetlands.

One of Mexico's oldest forest protection initiatives, originally decreed in 1938 and refreshed in 2002.

Important habitat for waterbirds such as egrets, herons, kingfishers, and neotropic cormorants, as well as the endangered Puebla frog.

The ecological character of the protected area changes with the seasons in ways that affect both scenery and wildlife observation. The rainy season, generally from late spring through early autumn, brings higher water levels in the reservoirs and rivers, fuller waterfalls, and lush green forest cover. Cooler, drier months from late autumn into early spring offer clearer views of the canyon landscapes, more comfortable hiking conditions in the forested terrain, and excellent waterbird observation along the reservoir margins. Visiting during drier months can also make the network of dams and reservoirs easier to view as integrated landscape features.