Water management challenges at Mushandike irrigation scheme in Runde catchment, Zimbabwe
Jose A. Malanco Hodson Makurira Evans Kaseke Webster Gumindoga
Abstract. Mushandike Irrigation Scheme, constructed in 1939, is located in
Masvingo District and is one of the oldest irrigation schemes in Zimbabwe.
Since 2002, the scheme has experienced severe water shortages resulting in
poor crop yields. The low crop yields have led to loss of income to the
smallholder farmers who constitute the irrigation scheme leading to water
conflicts. The water stress at the scheme has been largely attributed to
climate change and the uncontrolled expansion of the land under irrigation
which is currently about 1000 ha
against a design area of 613 ha. This study sought to determine the actual causes of water shortage
at Mushandike Irrigation Scheme. Hydro-climatic data was analysed to
establish if the Mushandike River system generates enough water to guarantee
the calculated annual yield of the dam. Irrigation demands and efficiencies
were compared against water availability and dam releases to establish if
there is any deficit. The Spearman's Rank Correlation results of 0.196 for
rainfall and 0.48 for evaporation confirmed positive but insignificant
long-term changes in hydro-climatic conditions in the catchment. Water
budgets established that the yield of the dam of
9.2 × 106 m3 year−1
is sufficient to support the expanded area of 1000 ha provided
in-field water management efficiencies are adopted. The study concludes that
water shortages currently experienced at the scheme are a result of
inefficient water management (e.g. over-abstraction from the dam beyond the
firm yield, adoption of inefficient irrigation methods and high channel
losses in the canal system) and are not related to hydro-climatic
conditions. The study also sees no value in considering inter-basin water
transfer to cushion the losses being experienced at the scheme.
CC BY 029 мая 2018
Тип материала: Статья
Тематика: WATER RESOURCES
Язык: EN
Ранее опубликовано
Copernicus GmbH
UNDERSTANDING SPATIO-TEMPORAL VARIABILITY OF WATER RESOURCES AND THE IMPLICATIONS FOR IWRM IN SEMI-ARID EASTERN AND SOUTHERN AFRICA, VOL 378