Location: Grassland Soil and Water Research Laboratory
Project Number: 3098-13610-009-099-A
Project Type: Cooperative Agreement
Start Date: Feb 1, 2024
End Date: Sep 30, 2025
Objective:
To parameterize a distributed groundwater flow model and salinity transport model across the conterminous U.S. The salinity model includes components for multiple salt ions in irrigation water, salt accumulation and leaching in the soil, salt transport in surface and ground water, and impact on plants. An additional objective is to test and validate the model for several watersheds across the country. The integrated model will be capable of simulating the impacts of land and water management on salt accumulation in soils and aquifers and transport in channels. The model will be available for use in developing national conservation policy as part of CEAP (Conservation Effects Assessment Project) and for business-as-usual and aspirational scenarios as part of LTAR (Long Term Agroecosystem Research).
Approach:
A new groundwater model, called GWFLOW, and a salinity model have been integrated into the SWAT+ code. Scripts will be written to develop required inputs for the GWFLOW and salinity models in SWAT+ for each of the 2,100 watersheds across the U.S. that constitute the National Agroecosystem Model. After the groundwater and salinity models have been parameterized, they will be validated for several watersheds with adequate monitored data, primarily in arid western regions. These new modules will enhance SWAT+ prediction capabilities in areas with complex surface/groundwater interactions and/or groundwater pumping for irrigation or municipal usage and will provide a new set of scenario capabilities for LTAR and CEAP.
