The leader of the El Escobal Women's Association (ASMUES) was found dead with signs of violence in a pasture on Wednesday.
Her neighbors last saw her on Tuesday at 18h00 local time, when she left her residence to a nearby road to wait for a package from downtown. Valderrama did not show up to meet the vehicle nor did she return home.
"A couple of hours after her disappearance, the entire neighborhood began to search for her. We were worried because she was very dear to everyone," community leader Norberto Fernandez said.
Thousands in Colombia continued their protests against police violence and inequality.
The Colombian police have used excessive force, killing at least 40 people, says rights group @TembloresOng.