GIS-Based Python Simulation of Infiltration over a Landscape

Abstract

Accounting for variation in infiltration over space and time is essential in planning for land management. One such example is the consideration of sites for mitigation wetlands, where knowledge of the water cycle is essential to a determination of whether a site will have sufficient water to support wetland functioning. A methodology and an implementing script (GAINS) were developed using the Green–Ampt equation to calculate instantaneous and cumulative infiltration, moisture content, and excess water on the land surface. Results are available in tabular form, as well in GIS maps displaying the individual parameters at a site at any given point in time. GAINS, written in Python, was demonstrated for a site within Pershing State Park in Missouri, a location that traditionally has supported wetlands. Results showed that the Green–Ampt equation was correctly modeled. The successful demonstration is an important step toward providing a single tool to support decision-making regarding potential wetland mitigation sites.