Korowya

Korowya
The Korowya River at Addi Kawa
Korowya River in Kola Tembien
Etymology	Named after the homonymous village
Location
Country	Ethiopia
Region	Tigray Region
District (woreda)	Kola Tembien
Physical characteristics
Source	Slopes of Tsili
• location	Haddinnet municipality
• elevation	1,908 m (6,260 ft)
Mouth	Tsaliet River
• location	3.5 km north of Addeha
• coordinates	13.4657°N 39.1011°E / 13.4657; 39.1011
• elevation	1,643 m (5,390 ft)
Length	12 km (7.5 mi)
Width
• average	50 m (160 ft)
Basin features
Progression	Tsaliet→ Wari→ Tekezé→ Atbarah→ Nile→ Mediterranean Sea
River system	Permanent river (low baseflow)
Landmarks	Mt. Itay Sarah, Mika’el Samba and Maryam Hibeto rock churches
Bridges	N of Addeha, on the road to Hawzien
Topography	Pediment surrounded by steep sandstone mountains

The Korowya is a river of the Nile basin. Rising in the mountains of Dogu’a Tembien in northern Ethiopia, it flows westward to empty finally in the Weri’i and Tekezé River.

The river in the radial drainage network of Dogu’a Tembien

Characteristics

It is a meandering stream in a semi-confined alluvial plain, with an average slope gradient of 31 metres per kilometre.^[1]

Flash floods and flood buffering

View from Tsili upper catchment towards Korowya

Runoff mostly happens in the form of high runoff discharge events that occur in a very short period (called flash floods). These are related to the steep topography, often little vegetation cover and intense convective rainfall. The peaks of such flash floods have often a 50 to 100 times larger discharge than the preceding baseflow.^[1] The magnitude of floods in this river has not been decreased due to interventions in the catchment. Physical conservation structures such as stone bunds^[2][3] and check dams are few and insufficient.^[4][5] On many steep slopes, there are remnant forests; the dense vegetation contributes to enhanced infiltration, but cannot buffer the floods.^[6]

Irrigated agriculture

Irrigation is strongly dependent on the river's baseflow. Such irrigated agriculture is important in meeting the demands for food security and poverty reduction.^[1] Irrigated lands are established in the lower alluvial plains of Korowya River, and near springs at the headwaters.

Boulders and pebbles in the river bed

From upstream to downstream, the following lithological units occur in the catchment.^[7]

• Lower basalt
• Amba Aradam Formation
• Antalo Limestone
• Adigrat Sandstone

Mostly the river bed is composed of sand, but one may find some pebbles, representing a mix of all lithologies crossed by the river.

From upper to lower Tembien

During its course, this river passes through two woredas.^[8] On the various parts:

• The headwaters are in Dogu’a Tembien
• Most of the lower plain is in Kola Tembien

Trekking along the river

A trekking route has been established along this river.^[9] The tracks are not marked on the ground but can be followed using downloaded .GPX files.^[10]

• Trek 21, along and parallel to Korowya River

In the rainy season, flash floods may occur and it is advised not to follow the river bed. At times it may be impossible to cross the river in the rainy season.^[11]

See also

• List of Ethiopian rivers

References

1. Amanuel Zenebe, and colleagues (2019). The Giba, Tanqwa and Tsaliet rivers in the headwaters of the Tekezze basin. In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District. SpringerNature. doi:10.1007/978-3-030-04955-3_14. ISBN 978-3-030-04954-6.
2. Nyssen, Jan; Poesen, Jean; Gebremichael, Desta; Vancampenhout, Karen; d'Aes, Margo; Yihdego, Gebremedhin; Govers, Gerard; Leirs, Herwig; Moeyersons, Jan; Naudts, Jozef; Haregeweyn, Nigussie; Haile, Mitiku; Deckers, Jozef (2007). "Interdisciplinary on-site evaluation of stone bunds to control soil erosion on cropland in Northern Ethiopia". Soil and Tillage Research. 94 (1): 151–163. doi:10.1016/j.still.2006.07.011. hdl:1854/LU-378900. Archived from the original on 28 April 2023. Retrieved 9 September 2020.
3. Gebeyehu Taye and colleagues (2015). "Evolution of the effectiveness of stone bunds and trenches in reducing runoff and soil loss in the semi-arid Ethiopian highlands". Zeitschrift für Geomorphologie. 59 (4): 477–493. Bibcode:2015ZGm....59..477T. doi:10.1127/zfg/2015/0166.
4. Nyssen, J.; Veyret-Picot, M.; Poesen, J.; Moeyersons, J.; Haile, Mitiku; Deckers, J.; Govers, G. (2004). "The effectiveness of loose rock check dams for gully control in Tigray, Northern Ethiopia". Soil Use and Management. 20: 55–64. doi:10.1111/j.1475-2743.2004.tb00337.x.
5. Etefa Guyassa and colleagues (2017). "Effects of check dams on runoff characteristics along gully reaches, the case of Northern Ethiopia". Journal of Hydrology. 545 (1): 299–309. Bibcode:2017JHyd..545..299G. doi:10.1016/j.jhydrol.2016.12.019. hdl:1854/LU-8518957. Archived from the original on 30 April 2023. Retrieved 9 September 2020.
6. Descheemaeker, K. and colleagues (2006). "Runoff on slopes with restoring vegetation: A case study from the Tigray highlands, Ethiopia". Journal of Hydrology. 331 (1–2): 219–241. doi:10.1016/j.still.2006.07.011. hdl:1854/LU-378900. Archived from the original on 28 April 2023. Retrieved 9 September 2020.
7. Sembroni, A.; Molin, P.; Dramis, F. (2019). Regional geology of the Dogu'a Tembien massif. In: Geo-trekking in Ethiopia's Tropical Mountains — The Dogu'a Tembien District. SpringerNature. ISBN 978-3-030-04954-6. Archived from the original on 8 March 2021. Retrieved 26 February 2020.
8. Jacob, M. and colleagues (2019). Geo-trekking map of Dogu'a Tembien (1:50,000). In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District. SpringerNature. ISBN 978-3-030-04954-6. Archived from the original on 8 March 2021. Retrieved 26 February 2020.
9. Description of trekking routes in Dogu'a Tembien. In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District. GeoGuide. SpringerNature. 2019. doi:10.1007/978-3-030-04955-3. ISBN 978-3-030-04954-6. S2CID 199294303. Archived from the original on 8 March 2021. Retrieved 26 February 2020.
10. "Public GPS Traces tagged with nyssen-jacob-frankl". Archived from the original on 4 June 2021. Retrieved 26 February 2020.
11. Nyssen, Jan (2019). "Logistics for the Trekker in a Rural Mountain District of Northern Ethiopia". Geo-trekking in Ethiopia's Tropical Mountains. GeoGuide. Springer-Nature. pp. 537–556. doi:10.1007/978-3-030-04955-3_37. ISBN 978-3-030-04954-6.