Essays on groundwater management strategies in water-scarce agriculture: case studies from South India
thesisposted on 29.03.2022, 02:05 by Deepa Pradhan
Groundwater resources, all across the globe, are being depleted at a rapid rate in order to meet the increasing demand for water, particularly for irrigation purposes. Managing the factors that affect the supply as well as demand for groundwater is crucial towards ensuring their sustainability. Cropping choices made by farmers determine, to a large extent, the amount of water used in agriculture. However, farmers in drought prone regions also face a trade-off between growing risky but more profitable and high water-intensive (HWI) crops on the one hand, and low risk but less profitable, low water-intensive and drought resistant (LWI/DR) crops on the other. Watershed development projects (WSD), institutional support programs and collective arrangements for groundwater management are some of the important strategies that have been introduced in the past to augment groundwater supply as well as to curtail excessive extraction. However, with persistent and increasing water scarcity over the years, it is unclear how effective such strategies have been. To understand the role and effectiveness of such physical, socio-economic and institutional interventions is an important policy concern that has not been addressed thus far. Using some relevant cases from Southern India, this thesis aims to understand the challenges associated with sustainable groundwater management in the above-mentioned context. First, using the propensity score matching (PSM) method, I look at the impact of WSD project interventions on influencing cropping patterns in Andhra Pradesh, India. Results suggest that implementation of WSD projects is positively associated with the share of HWI crops and negatively associated with the share of LWI/DR crops, thereby potentially neutralising the groundwater recharge benefits of WSD projects. However, the association of WSD projects with the share of two types of LWI/DR crop combinations is also found to be positive in some cases, thereby indicating that farmers (or some farmer types) in WSD regions also potentially display risk hedging behaviour. Using a multinomial logit model, I further find that rich farmers with tubewell ownership are more likely to grow HWI crops. Poorer farmers, such as those belonging to lower social caste, exhibit higher risk hedging behaviour as they are more likely to grow LWI/DR crop choices. Secondly, moving on to the groundwater demand management challenges, this thesis explores the existence of potential linkages between institutional support programs that have been promoted in these regions and crop choices made by farmers. In particular, the focus of this thesis has been on evaluating three types of institutional interventions in Andhra Pradesh, namely, crop water budgeting (CWB), farmer field schools (FFS) and soil-moisture conservation promotion activities. A multivariate probit analysis indicates that there is a positive and significant correlation between participation in CWB/FFS and the choice of HWI crops, thereby raising questions over the effectiveness of such programs in mitigating excessive groundwater extraction. However, there is also a positive correlation found between soil-moisture conservation efforts and the choice of LWI/DR crops. Similar to the results obtained previously, a multinomial logit model application further supports the finding that rich farmers with better access to water are positively associated with growing HWI crops. Finally, I look at the implications of farmers’ participation in bore pool sharing collective arrangements on their crop incomes and crop choices. A Probit-Two staged least squares (Probit-2SLS) model and PSM method are used to help with this analysis. Formation of bore sharing groups is encouraged with the intention of discouraging excessive (and competitive) bore well digging by providing critical and timely irrigation to rainfed plots and discouraging the cultivation of HWI crops. Based on the analysis conducted using household data obtained from Andhra Pradesh and Telangana states, the results indicate that there is a positive association between farmers’ participation in such collectives and their crop incomes. However, the results also indicate that the share of HWI crops and farmers’ participation in bore pool sharing groups are positively associated. Such associations are even more pronounced where the ratio of number of bore wells to the number of households is higher for a given bore pool sharing group. Similarly, farmers who have had multiple failed attempts at digging bore wells also have positive association with more intensive participation in such collective arrangements for extracting groundwater. From an equity perspective, the findings of this thesis suggest that the benefits of groundwater augmentation projects and programs get largely captured by richer farmers thereby further exacerbating the socio-economic inequality.