Gereb Segen is a reservoir located in the Inderta woreda of the Tigray Region in Ethiopia.

The earthen dam that holds the reservoir was built in 2016 by the Tigray Water Bureau, with the main aim of providing Mekelle with water.

In 2018-2019 the reservoir was unable to sustain the water needs of Mekelle

[2] Part of the water is lost through seepage;[3] the positive side-effect is that this contributes to groundwater recharge,[4] and it allows irrigation by the downstream communities.There is a (much smaller) reservoir with the same name, some 20 km to the southeast: Gereb Segen (Hintalo).

On August 19, 2024 the spillway of the dam collapsed, also damaging the downstream irrigation canal.