An Agricultural Package for MODFLOW 6 Using the Application Programming Interface

Area of Science:

• Groundwater Hydrology
• Water Resource Management
• Computational Hydrogeology

Background:

• Accurate simulation of agricultural water use is crucial for sustainable groundwater management.
• Existing MODFLOW packages have limitations in representing complex irrigation practices.
• The MODFLOW Application Programming Interface (API) offers a flexible framework for package development.

Purpose of the Study:

• To develop and validate a new agricultural water use package for MODFLOW 6 using the API.
• To enhance the simulation of irrigation demand, including deficit and over-irrigation scenarios.
• To expand support for diverse irrigation providers and grid types within MODFLOW.

Main Methods:

• Development of the MODFLOW API Agricultural Water Use Package (API-Ag) based on prior AG Package approaches.
• Implementation of new features: deficit/over-irrigation, Multi-Aquifer Well and Lake Package support.
• Validation using three example problems demonstrating improved representation of managed systems.

Main Results:

• The API-Ag Package successfully simulates irrigation demand and delivery.
• New features provide a more realistic representation of agricultural water use.
• Simulated irrigation volumes show excellent agreement with the MODFLOW-NWT AG Package.

Conclusions:

• The API-Ag Package is a valuable advancement for MODFLOW 6, improving the simulation of agricultural water use.
• It offers enhanced capabilities for modeling highly managed groundwater systems.
• The package supports a wider range of irrigation scenarios and model configurations.