Performance Evaluation of Karfe Small-Scale Irrigation Scheme: (A case Study of Karfe Small Scale Irrigation Scheme East Shoa Bishoftu,
| dc.contributor.advisor | Daneal Fekeresslasie | |
| dc.contributor.author | Enanye Tadege | |
| dc.date.accessioned | 2026-08-04T21:26:33Z | |
| dc.date.available | 2026-08-04T21:26:33Z | |
| dc.date.issued | 2026-05 | |
| dc.description.abstract | The performance of small-scale irrigation schemes is necessary for increasing agricultural productivity and ensuring sustainable water resources management. This study assessed the hydraulic, agronomic, and structural performance of the Karfe Small-Scale Irrigation Scheme (65 ha), which diverts water from the Mojo River using a broad-crested weir and serves 162 households through right (2,250 m) and left (1,503 m) main canals. The evaluation was conducted during the main wheat cropping season (07 January–30 April 2026), considering spatial variability across head, middle, and tail sections of the command area. A mixed-methods approach was applied, combining field measurements, laboratory soil analysis, and farmer interviews. Soil were analysed for texture, bulk density, and soil moisture characteristics using standard laboratory equipment, while irrigation performance parameters were measured using bucket–stopwatch flow measurement techniques and canal observations. Performance indicators were computed based on FAO, IWMI, Bos et al. Khosla, and Terzaghi standards. The results show that the soils are dominantly clay (average 55.39%), with bulk density ranging from 1.10–1.13 g/cm³, field capacity of 0.37–0.41 m³/m³, and total available water of 130–170 mm/m. Application efficiency averaged 54.82% (moderate), while storage efficiency averaged 89.10%. Water supply indicators shown spatial imbalance, with SAR (1.08), RI (50% at tail), and DPR (0.58) confirming over-supply at the head and deficits at the tail. Conveyance efficiency averaged 76.09% (moderate), while distribution uniformity was 75%. Structural evaluation showed poor conditions with an average SCI of 2.36 and EI of 33.93%, indicating significant infrastructure deterioration. Major hydraulic failures were also observed, including misaligned weir (12.4° deviation), insufficient stilling basin length (2.19m deficit), floor length (1.55m) ,Froude number (3.93m) and FS Sliding(1.45),FS Overturning 1.88 the retaining wall instability under seismic loading and water Pressure. Based on these findings, mitigation measures including redesigned the retaining wall in two options (option1) is Masonry, option 2 reinforced concrete retaining wall) as alternative, canal rehabilitation, structural repair, improved irrigation scheduling, and strengthening of water user management are recommended to enhance overall system performance and sustainability. | |
| dc.identifier.uri | https://etd.aau.edu.et/handle/123456789/8806 | |
| dc.language.iso | en | |
| dc.publisher | Addis Ababa University | |
| dc.subject | Small-scale irrigation | |
| dc.subject | Water supply | |
| dc.subject | Conveyance efficiency | |
| dc.subject | Karfe | |
| dc.subject | IWMI | |
| dc.title | Performance Evaluation of Karfe Small-Scale Irrigation Scheme: (A case Study of Karfe Small Scale Irrigation Scheme East Shoa Bishoftu, | |
| dc.type | Thesis |