Centre for Development Economics
Department of Economics
Delhi School of Economics
ANNOUNCE A SEMINAR
Shallow Gains, Deep Losses: The Limits of Uniform Groundwater Regulation
by
Anshuman Tiwari
( University of Chicago)
(Thursday, August 21, 2025, at 3:00 PM, IST )
Venue: Amex Room
Abstract:-
Many major aquifers across the world are depleting as extraction outpaces recharge. Where pricing is infeasible, regulators rely on uniform rules, typically critiqued for inefficiency under heterogeneity. We show a starker risk of compliance without conservation in the case of a uniform timing mandate in the Indian states of Punjab and Haryana that shifted the crop calendar toward the monsoon. The mandate aimed to raise water tables by lowering evapotranspiration from pumping and increasing rainfall’s share of irrigation, but it also reduced yields due to the sub-optimal timing. Effectiveness for water conservation turns on hydro-physical heterogeneity: where extent of recharge depends on depth to water, shallow wells may stabilize while deeper wells continue to fall. We develop a simple model of land and irrigation choices under a productivity-lowering timing mandate and show theoretically that farmers expand acreage under a binding subsidized-electricity ration when delayed cultivation increases the usability of rainfed irrigation. Using a synthetic difference-in-differences design, we find evidence consistent with this land response. But water table rises by 0.25 m only in the shallowest quartile of wells, with no aggregate increase, underscoring the role of hydro-physical heterogeneity. Finally, rice yields decline by 3.5% on average.