TITLE:
Evaluation of Water Delivery Performance of Nkhafi Irrigation Scheme in Dowa District, Malawi, Africa
AUTHORS:
Davis Sibale, Godfrey Mwenelupembe, Sylvester Chikabvumbwa, Sylvester Chisale
KEYWORDS:
Adequacy, Water Delivery Efficiency, Equity, Dependability, Irrigation Efficiency
JOURNAL NAME:
Computational Water, Energy, and Environmental Engineering,
Vol.10 No.3,
June
3,
2021
ABSTRACT: This study evaluated the water delivery performance
of Nkhafi irrigation scheme based on adequacy, water delivery efficiency,
equity, dependability and irrigation efficiency. Primary data were collected
from field measurements, scheduled interviews, group
discussions and use of a structured questionnaire. CROPWAT 8.0 computer model
was used to determine crop water requirements and irrigation requirements. The results revealed that adequacy, water
delivery efficiency, equity, dependability and overall water delivery
performance were (0.74; 0.82), (0.70; 0.80), (0.15; 0.20), (0.11; 0.21) and
(0.80; 0.80) for 2017 and 2018 seasons respectively. The scheme overall
irrigation efficiencies were 20% and 25% for 2017 and 2018 respectively. These
findings revealed that scheme users failed to deliver adequate and dependable
water in an effective manner in both growing seasons. This occurred due to
insufficient water supply, poor irrigation scheduling, lack of adequate
knowledge and skills in operating and rehabilitating hydraulic structures,
siltation and water losses through seepage in canals. Therefore, it is
recommended that major maintenance works need to be done along the whole canal
network in order to achieve good overall water delivery performance.
Furthermore, farmers need to be trained in water management, sustainable
agricultural production practices, operation and maintenance of irrigation
structures. The study has provided an insight on the status of the scheme hence
encouraging scheme users to improve water delivery performance.