The Lagunienu is 7.27 kilometres (4.52 mi) long.
It flows through the commune of Porto-Vecchio.
There are no named tributaries.[1]
The stream rises to the northwest of the hamlet of Renajolo and flows in a generally southeast direction past the village of Palavesa to enter the Golfe de Porto-Vecchio between Poretta and Marina di Fiori.[2]
There are east-facing beaches on either side of the mouth of the Lagunienu.[3]