San Patricio River (Spanish: Río San Patricio) is a river in the municipality of Ponce, Puerto Rico.San Patricio River has its origin in the sector called Corcho, in the municipality of Utuado.[5] The river's course is southward from Utuado and into barrio San Patricio of the municipality of Ponce.After progressing south through barrio San Patricio, the river enters barrio Maragüez also in the municipality of Ponce.From there it continues its southerly progression until it feeds into Río Cerrillos.