[3] It is a confined river, locally meandering in its narrow alluvial plain, with a slope gradient of 15 metres per kilometre.

[4] Main tributary is Kalamino River which drains a large part of Mekelle; it joins May Gabat downstream from the Gereb Segen reservoir.

Peak discharges up to 190 m³ per second occur in the second part of the rainy season (month of August) when there are strong rains and the soils are saturated with water in many places.

The highest sediment concentrations occur at the beginning of the rainy season, when loose soil and dust is washed away by overland flow and ends up in the river.

[5] As such water contains many nutrients (locally it is called "aygi"), farmers estimate that it strengthens their cattle, which they will bring to the river.

[5] It is anticipated that the mentioned values have strongly decreased after construction of the Gereb Segen reservoir, because it intercepts water and sediment.

On steep slopes, exclosures have been established; the dense vegetation largely contributes to enhanced infiltration, less flooding and better baseflow.

[18] Trek 18, through the southwestern mountains of Dogu'a Tembien, allows panoramic views on lower May Gabat (including Gereb Segen reservoir) and the river mouth.