Many regions worldwide have replaced quotas, as a means to controlling irrigation-water usage, with a hybrid policy that integrates private quotas and uniform prices. This paper characterizes the political equilibrium in a game in which farmers lobby for lower prices and larger quotas. We show that combining the two instruments reinforces the robustness of each against political distortion; consequently, a hybrid policy that follows a quotas-only regime reduces water usage. However, the social welfare rank of the hybrid policy versus the quotas-only and price-only counterparts is an empirical question. We use the equilibrium conditions to derive a structural discrete/continuous choice model that enables estimating the agricultural sector’s lobbying power and the level of political organization used to reduce prices. We employ the model to data from Israel during the 1980s; during that period, quotas were set at a village-specific level and prices were set at a region-specific level, thereby generating the variability required to estimate the model’s parameters. We obtain empirical support for the reinforcement hypothesis and evidence of strong political influence, but also evidence of considerable free-riding regarding price reduction. Simulations of political equilibria under the quotas-only, price-only and hybrid regimes indicate a domination of the latter in terms of social welfare.