Serious about Managing Groundwater Depletion? Shift Focus from “Water-Saving” Technologies to Motivating Irrigation Behavior
Irrigation technologies, such as drip lines, moisture probes and automated systems, are often viewed as solutions to reduce groundwater depletion. Yet, in Jordan, groundwater levels continue to drop even though the majority of land has been irrigated using such technologies for the past 20 years. It turns out that perception of water shortages in the past can affect current irrigation behavior in ways that exacerbate the groundwater problem. A recent study of 400 commercial farms in the highlands of Jordan by researchers from the International Water Management Institute (IWMI) and Texas A&M AgriLife shows that farmers who faced water shortages and agricultural losses in the past tend to irrigate more frequently than the schedule recommended for the hot and dry climate and use self-judgment in determining irrigation needs, as opposed to using a crop calendar or moisture probe. As shown previously, farmers resort to applying more irrigation to avert the risk of crop loss.
In the Near East and North African (NENA) region, rapidly depleting groundwater reserves coupled with frequent and intense droughts have significantly impacted the agricultural sector and the overall economy. If the current trends of groundwater depletion and greenhouse gas emissions are left unchecked, drought alone is projected to reduce the regional gross domestic product (GDP) by up to 6% by 2050. Governments in the region have been trying to reduce the risk of crop losses from drought and, at the same time, reduce the rate of groundwater depletion. Farmers have been encouraged to use “water-saving” irrigation technologies, such as drip irrigation, soil moisture sensors and automated systems, so as to avoid unnecessary irrigation. Most farmers have used such technologies for the last couple of decades, as governments have promoted and subsidized them. However, the rate of groundwater depletion continues at an alarming rate (~1 meter/year).
Technologies on their own may not be sufficient to manage groundwater better. Understanding farmers’ irrigation behavior and its linkages to past drought events is important because irrigation decisions are primarily driven by maximizing profit or minimizing the risk of crop loss, not by preserving groundwater resources.
The IWMI study, funded by USAID and Mercy Corps Jordan, found that about 60% of Jordanian farms reported experiencing severe water shortages (physical availability of water) in the past 10 years. The lack of water was so severe that 60% of farms that faced water shortages had to reduce cultivation area to cope with it. Among these farms, almost 84% reported the loss of agricultural production due to water shortages, and 57% reported the loss of income. While almost all farms used irrigation technologies, such as drip lines and pressure-compensating devices, more than 64% of farmers applied irrigation more frequently than the recommended schedule. For example, 25% of farmers who faced water shortages in the past reported irrigating olive trees daily to reduce the risk of crop failure. Paradoxically, irrigating olive trees every day can reduce yields.
The study found that farms that reported severe water shortages in the past were 4% more likely to apply irrigation more frequently and 19% more likely to use self-judgment in determining irrigation needs. These relationships were stronger for smaller farms (< 20 hectares), farms with sandy soil and the farms managed by owners themselves (as compared to employed managers). However, past experience of water shortages did not increase the probability of irrigation frequency or self-determined irrigation for those who sought irrigation advisory information.
Policymakers may need to shift their focus from supplying the irrigation technologies to providing quality irrigation advisory services for farmers, which has received less attention and public funding. Providing “nudges” to farmers to make them aware of the relationship between irrigation behavior and groundwater depletion and its consequences of higher pumping costs and lower incomes in the future may moderate irrigation behavior. Since similar groundwater management challenges exist in other countries in the NENA region, policymakers may want to consider designing and delivering irrigation advisory services that complement the use of irrigation technologies. Tailoring the irrigation advisory services to farmers’ past experience of water scarcity and crop losses, as well as landholding size and cropping pattern, may help reduce the rate of groundwater depletion by altering irrigation behavior.
This post is based on a research series paper published by the International Fund for Agricultural Development (IFAD), available on their website.