The Rio Santa Maria da Vitória is a 122-kilometer river in the central region of Espírito Santo state, originating at Serra do Garrafão in the municipality of Santa Maria de Jetibá and flowing eastward through Santa Leopoldina, Cariacica, and Serra before emptying into the Baía de Vitória. Its watershed covers approximately 1,876 km² and is bounded to the north and west by the basins of the Rio Reis Magos and Rio Doce, and to the south by the basins of the Rio Jucu, Rio Bubu, and Rio Formate.

The river descends from the mountainous interior toward the coast, passing through a landscape that has been heavily altered by human activity. The basin supports agriculture — predominantly horticulture — along with industrial production, hydroelectric generation, and public water supply. Three reservoirs exist within the basin: Duas Bocas, which serves as a public water supply reservoir, and two hydroelectric reservoirs, Rio Bonito and Suíça. Paddlers should be aware that these impoundments interrupt the natural river corridor and will affect route planning along the main stem.

Water quality is a notable concern. The river and its basin have been affected by deforestation in riparian protection zones, bank sedimentation, widespread use of agrochemicals, and inadequate disposal of solid and liquid waste, including domestic sewage from the communities along its course. The river is classified as Class 2 under Brazil's CONAMA Resolution 357/2005, indicating it is intended to support primary contact recreation, but actual conditions vary given the documented pressures on the watershed.

The river's principal tributaries include the rios Possmoser, Claro, São Luiz, Bonito, da Prata, Mangaraí, Caramuru, Duas Bocas, Triunfo, Farinhas, Fumaça, and São Miguel. Fish species in the river include redbreast tilapia, mutton snapper, and fat snook. The river has historical significance as a travel corridor into the Espírito Santo interior; in the late 19th century, Therese of Bavaria traveled by canoe along the Santa Maria da Vitória from Vitória toward the mountain region.