The Igaraçu River, also called the Igarassu River, is a

distributary A distributary, or a distributary channel is a stream channel that branches off and flows a main stream channel. It is the opposite of a ''tributary'', a stream that flows another stream or river. Distributaries are a result of river bifurc ...

of the

Parnaíba River The Parnaíba River ( ) is a river in Brazil, which forms the border between the states of Maranhão and Piauí. Its main course is long and the Parnaíba River Basin covers .Ramos, T.P.A.; Ramos, R.T.C.; and Ramos, S.A.Q.A. (2014). Ichthyofaun ...

in northern

Piauí Piauí ( ) is one of the states of Brazil, located in the country's Northeast Region, Brazil, Northeast Region. The state has 1.6% of the Brazilian population and produces 0.7% of the Brazilian GDP. Piauí has the shortest coastline of any coas ...

state in

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. It flows from its origin on the Parnaiba River southwest of the city of

Parnaíba Parnaíba () is a city in the Brazilian state of Piauí. Having a population of over 169,000 inhabitants according to IBGE's 2024 estimates, it is the second most populous city in the state, after the capital Teresina. It is one of the four coast ...

to the mouth on the

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

near the city of Luís Correia. The river has sections classified as Environmental protection area by

ICMBio The Chico Mendes Institute for Biodiversity Conservation ( Portuguese: ''Instituto Chico Mendes de Conservação da Biodiversidade'', ICMBio) is a government agency under the administration of the Brazilian Ministry of the Environment. It is nam ...

See also