HYDRAULIC PERFORMANCE EVALUATION OF SMALL SCALE IRRIGATION  SCHEME; CASE STUDY OF ALLAWUHA IRRIGATION SCHEME, NORTH  WOLLO, ETHIOPIA
Creators: name: HABTAMU ABAY ESHETIE
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2017

description: Performance assessment in irrigation systems plays a vital role in identifying the gaps and 
applying mitigation measures. The water delivery performance of  the physical structures 
in Allawuha irrigation scheme was not clearly understood so far; hence the objective of 
the study was evaluating the hydraulic performance of Allawuha small scale irrigation 
scheme. This study was carried out for a single irrigation season from February to June, 
2016. Hydraulic performance of the scheme was evaluated by assessing  irrigation water 
supply  versus  demand and using 10 internal process indicators classified under water 
delivery and maintenance indicators.  
As per the results, deficit in supply was observed during April and May, which was 35.16 
and 25.53% respectively. However, supply was exceeding the demand by 60.47% during 
March. The highest spatial deficit was observed at  the last outlet point and  the lowest at 
the first outlet point. The overall water delivery performance of the canal in relation to 
adequacy, dependability, equity and efficiency were found to be 0.56, 0.47, 0.22 and 0.96 
respectively. Therefore, water delivery  performance of the  canals was poor in terms of Performance assessment in irrigation systems plays a vital role in identifying the gaps and 
applying mitigation measures. The water delivery performance of  the physical structures 
in Allawuha irrigation scheme was not clearly understood so far; hence the objective of 
the study was evaluating the hydraulic performance of Allawuha small scale irrigation 
scheme. This study was carried out for a single irrigation season from February to June, 
2016. Hydraulic performance of the scheme was evaluated by assessing  irrigation water 
supply  versus  demand and using 10 internal process indicators classified under water 
delivery and maintenance indicators.  
As per the results, deficit in supply was observed during April and May, which was 35.16 
and 25.53% respectively. However, supply was exceeding the demand by 60.47% during 
March. The highest spatial deficit was observed at  the last outlet point and  the lowest at 
the first outlet point. The overall water delivery performance of the canal in relation to 
adequacy, dependability, equity and efficiency were found to be 0.56, 0.47, 0.22 and 0.96 
respectively. Therefore, water delivery  performance of the  canals was poor in terms of adequacy and dependability;  however it was good and fair  for  efficiency and equity
respectively. Similarly, delivery performance ratio and equity ratio for head to tail were 
found to be 0.74 and 2.73 respectively. These values indicate, the existing performance of
the main canal was declined  as compared with  the intended and  also management  of
delivery  was poor  from  head  to  tail  reach of the system. Maintenance indicators  like
water surface elevations ratio, effectiveness of infrastructure and sustainability of 
irrigated area were found to be  78%,  28.13% and 97.8% respectively.  These values 
indicate that, actual water level as well as command area was reduced from initially 
designed, and a number of structures initially installed were become nonfunctional. 
Based on the results from this study non-proportionality of irrigation water demand with
supply, poor water delivery system, absence of frequent maintenance, and  the
management aspects were problems  strongly affecting  the hydraulic performance of the 
scheme. Therefore, it is suggested that, frequent maintenance, optimal crop plan, and
apply a strong water delivery plan are required to mitigate these problems.