ABSTRACT:

This manuscript shares data and code used in the manuscript:
Ndlovu W, S Zipper, T Foster (2025). Assessing the effectiveness of irrigator-driven groundwater conservation programs to drought: a case study of the northwestern Kansas Local Enhanced Management Areas. Agricultural Water Management.
Please cite the manuscript if you use this data/code.

Manuscript abstract:
Groundwater pumping for irrigation has led to declining groundwater levels in agricultural areas around the world, including the U.S. High Plains Aquifer. Here, we used a process-based crop model, AquaCrop, to assess the effectiveness of different irrigation management strategies during a synthetic multi-year drought. We focused on the Groundwater Management District 4 Local Enhanced Management Area (GMD-4 LEMA), a regional groundwater conservation program in the northwestern Kansas portion of the High Plains Aquifer. We first calibrated corn and sorghum AquaCrop models to simulate yield and irrigation using the Particle Swarm Optimization algorithm, and then applied a novel difference-based bias correction method to improve performance. We found that the corn models outperformed the sorghum models, likely due to limited observational sorghum data. However, both models performed satisfactorily during drought periods. We then evaluated the effectiveness of the groundwater conservation program in reducing water use during a synthetic five-year drought under three irrigation strategies. During the synthetic drought, corn irrigation requirements were roughly double those of sorghum. However, even simulated corn irrigation needs were generally less than current water allocations, supporting past work that suggests the current GMD-4 LEMA water allocations are ineffective for conserving water. Model simulations also indicated that water conservation strategies could reduce annual irrigation requirements without a substantial reduction in crop yield through improved water use efficiency, suggesting that lower allocations would be a feasible approach to reduce irrigation and slow groundwater decline rates.

ABSTRACT:

Kampoosa Bog is a 465 ha wetland complex located in Stockbridge-Lee MA that is currently being impacted by road salt pollution. In an effort to understand the impacts of road salt on the water quality and vegetation in the wetland, the Mass DOT and Department of Fish and Wildlife have collaborated with engineers at the University of Massachusetts to monitor the water quality at gauge stations (KB100, KB150, KB300) within the Kampoosa watershed. At these gauge stations water flow, water temperature and specific conductance are recorded at a 15 minute interval as of Nov 2017. Using road salt application, groundwater and surface water chemistry, and streamflow data collected between 2012 and 2019 we quantify the accumulation of road salt in the Kampoosa Bog subwatersheds.