Presa Endhó

Presa Endhó fills part of the Tula plains in the Mezquital Valley, between the municipalities of Tepetitlán and Tula de Allende, at about 2,000 metres above sea level and some 100 kilometres north of Mexico City. It was built between 1947 and 1951 to hold the water entering the local irrigation district and to store it in dry spells. The dam wall is masonry and compacted earth with basalt rock, 60 metres high, and it holds a reservoir of 1,260 hectares.

This is not a leisure lake. Since 1975, when the Túnel Emisor Central was finished, the dam has received sewage from the Valle de México metropolitan drainage system, and the Endhó canal carries that water to the Tula and Alfajayucan irrigation districts. The Michimaloya river also flows into the reservoir. According to Wikipedia, wastewater irrigation grew from about 14,000 hectares in 1926 to some 85,000 today, and studies report heavy-metal contamination in the dam and in wells of neighbouring communities.

Local news in recent years centres on water hyacinth and the Culex mosquito. According to Conagua, the area covered by hyacinth fell from 900 hectares in October 2025 to 443 in June 2026 after 105 thousand cubic metres of weed were removed with machinery; spraying against the mosquito has run since 1 May 2026 across 27 riverside communities, and in August Conagua and Tepetitlán agreed to reinforce the Plan Maestro de Recuperación. Native vegetation along the shore is thorn scrub, mesquite, agave and cacti.