Investing in irrigation is often considered to be a viable approach to not only raising crop yields and farm incomes, but also mitigating the adverse effects of climate variability. This is particularly true in Malawi, where most of the economy depends on agriculture, and where frequent and severe droughts exacerbate poverty and food insecurity. Despite potential benefits, there are concerns raised about irrigation’s apparent low profitability and its possible displacement of higher return investments.
On Friday, 10th February, IFPRI-Lilongwe held a brownbag seminar led by Dr. James Thurlow, IFPRI Senior Research Fellow, on evaluating irrigation investment in Malawi. Dr. Thurlow presented on a recent study conducted by researchers at IFPRI and Ms. Franziska Schuenemann from the Kiel Institute for the World Economy. The study evaluates the economy-wide impacts of undertaking irrigation investments in Malawi at the scale envisaged by the Irrigation Master Plan. The study estimates irrigation returns based not only on increased crop yields, but also on reducing the adverse effects of climate variability, and allowing for a larger second or winter season crop, in addition to enhancing the effectiveness of other investments, such as fertilizer.
Using an approach that combines crop and economic models to account for farm investments and weather variability, the study evaluates the returns to irrigation arising through both economic and biophysical impact channels. In his presentation, Dr. Thurlow showed how farm investments in irrigation and fertilizer affect crop yields. Crop model results show how irrigation not only increases rain-fed maize yields, but how it enhances the gains from using fertilizer and reduces the yield variability caused by weather fluctuations. Irrigation offers synergies with the Farm Input Subsidy Program (FISP) while also strengthening the resilience of the agricultural system.
The study estimates the economy-wide returns of four different irrigation investment scenarios:
- Straight yield gain: where there is an expansion of 300,000 hectares of land under irrigation during summer cropping.
- Second season: expand winter cropping land by either 100,000 or 300,000 hectares
- Reduced variability: allow for randomly drawn weather realizations and compare outcomes with and without irrigation
- Fertilizer interaction: incorporate the synergies of using both fertilizer and irrigation together
Thurlow concluded that, while concerns over irrigation’s profitability are warranted, broader non-monetary benefits, such as greater food security, lower poverty, and reduced exposure to climate variability, may justify including irrigation within a national agricultural investment plan. Specifically, investing in irrigation can benefit the agricultural sector and broader economy: 62% of maximum benefits come from enabling a second season ($80 mil.), 19% come from yield gains on summer crops ($24 mil.), 10% are from interactions between fertilizer and irrigation ($13 mil.) and 9% come from reducing the effects of climate variability ($11 mil.). Ensuring that irrigation can and is used for winter cropping will be essential for any new investment plan.
The full seminar presentation is available below.
