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Frequent droughts, seasonal precipitation, and growing agricultural water demand in the Yakima River Basin (YRB), located in Washington State, increase the challenges of optimizing water provision for agricultural producers. Increasing water storage through managed aquifer recharge (MAR) can potentially relief water stress from single and multi-year droughts. In this study, we developed an aggregated water resources management tool using a System Dynamics (SD) framework for the YRB and evaluated the MAR implementation strategy and the effectiveness of MAR in alleviating drought impacts on irrigation reliability. The SD model allocates available water resources to meet instream target flows, hydropower demands, and irrigation demand, based on system operation rules, irrigation scheduling, water rights, and MAR adoption. Our findings suggest that the adopted infiltration area for MAR is one of the main factors that determines the amount of water withdrawn and infiltrated to the groundwater system. The implementation time frame is also critical in accumulating MAR entitlements for single-year and multi-year droughts mitigation. In addition, adoption behaviors drive a positive feedback that MAR effectiveness on drought mitigation will encourage more MAR adoptions in the long run. MAR serves as a promising option for water storage management and a long-term strategy for MAR implementation can improve system resilience to unexpected droughts. 

Identifying and treating erosion‐prone, critical source areas (CSA) presents the opportunity to effectively address erosion at a watershed scale. Social and financial drivers of conservation adoption, however have buffered implementation. An integrated systems understanding is needed to identify internal feedbacks and potential synergistic conservation policies. We simulate the physical, social, and financial incentive interactions with a high‐level system dynamics model to understand the conservation adoption and subsequent erosion behavior of the system. A Bass diffusion model integrated with physical modeling results enables the simulation of CSA, the diffusion of innovations, and payment for conservation practices. Land retirement and tillage reduction best management practices are assessed for the dryland wheat farming region in the Inland Pacific Northwest of the United States. Model utility was confirmed with quantitative land management data and qualitative local expertise. Historical, voluntary‐based efforts to reduce erosion suffer marginal returns. We conclude that: (1) All targeting of CSA reduces long‐term erosion rates; (2) The most effective use of conservation funds, however, occurs when the diffusion of innovation mechanism is reinforced by broad‐scale payments for tillage reduction; and (3) By identifying and utilizing positive feedback, our simulations suggest large gains in erosion reduction and conservation fund efficiency are possible.