Small-scale hydroelectric dams with a capacity of under 30 MW are seen by the authorities in Mexico as an important alternative for generating energy. But local communities reject them on the argument that they would cause social, economic and environmental damages. On the front line of the struggle are communities in the southern states of Puebla, Tabasco, Veracruz, Oaxaca and Chiapas, where there is great potential to harness hydro energy with small dams. “They claim the so-called mini-hydroelectric plants don’t have a negative impact on communities, but people already have the necessary information to know that any kind of dam has an impact,” activist Angélica Castro, coordinator of public advocacy and citizen participation in Services for Alternative Education (EDUCA), told IPS. EDUCA, a non-governmental organisation in Oaxaca, has been working since 2006 with the people of 39 communities in six municipalities in that state that would be affected by a 510 MW dam that the state Federal Electricity Commission (CFE) plans to build on the Verde River.