The Ribeirão Taquaruçu Grande is a significant watercourse in the state of Tocantins, Brazil. It is a primary tributary feeding the reservoir that supplies the state capital, Palmas, and is responsible for approximately 66% of the city's water supply. This underscores its vital ecological and infrastructural role in the region. One notable natural feature along its course is the Cachoeira do Evilson, a waterfall with a reported drop of 25 meters. This waterfall is located near the community of Taquaruçu. The presence of this waterfall is a key geographical characteristic and a potential sight for paddlers, though it also represents a significant and dangerous hazard requiring advanced scouting and portage. The water body is the focus of local conservation efforts, including educational initiatives led by organizations like the Conselho Indigenista Missionário Goiás/Tocantins and the Associação Água Doce – Movimento de Proteção ao Taquaruçu Grande, highlighting community awareness of its importance.