Approved for public release; distribution is unlimited. been used widely to assess the effects of drainage systems on wetlands. However, it can also be used to describe the hydrology of wetlands that are undrained. Model parameters include weather data, soil properties, seepage dynamics, and drainage system properties. DRAINMOD can be downloaded here: https://www.bae.ncsu.edu/agricultural-water-management/drainmod/ Hydrologic Simulation Program -Fortran (HSPF). HSPF simulates for extended

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... s of time the hydrologic, and associated water quality, processes on pervious and impervious land surfaces and in streams and well-mixed impoundments (Bicknell et al. 1997) . HSPF is capable of computing streamflow from continuous rainfall. HSPF simulates interception of soil moisture, surface runoff, interflow, baseflow, snowpack depth and water content, snowmelt, evapotranspiration, ground-water recharge, dissolved oxygen, biochemical oxygen demand, temperature, pesticides, conservatives, fecal coliforms, sediment detachment and transport, sediment routing by particle size, channel routing, reservoir routing, constituent routing, pH, ammonia, nitrite-nitrate, organic nitrogen, orthophosphate, organic phosphorus, phytoplankton, and zooplankton. HSPS can be downloaded here: https://www.epa.gov/ceam/hydrological-simulation-program-fortran-hspf Modular Finite-Difference Groundwater Flow Model (MODFLOW). MODFLOW, which is the most widely used groundwater model in the world, is capable of multi-dimensional simulations (USGS Fact Sheet, FS-121-97). It is capable of modeling exchange between surface and ground water systems including rivers, ephemeral streams, and reservoirs. It has been used extensively on the effects of groundwater withdrawals on water tables. MODFLOW can be downloaded here: https: //www.usgs.gov/software/modflow-6-usgs-modular-hydrologic-model Gridded Surface Subsurface Hydrologic Analysis (GSSHA). The principal purpose of the GSSHA is to model important watershed processes. GSSHA can be used as an episodic or continuous model where soil surface moisture, groundwater levels, stream interactions, and constituent fate are continuously simulated. The fully coupled groundwater-to-surface water interaction allows GSSHA to model basins in both arid and humid environments. The model is capable of computing flows, stream depths, and soil moisture and can account for hillslope processes (e.g., subsurface interflow and return flow). GSSHA is highly useable on Department of Defense installations to predict impacts of training operations. GSSHA 2.0 includes a new capability to model wetlands using two parts: conceptual and physical components. GSSHA can be downloaded here: https://www.gsshawiki.com/GSSHA_Download CONCLUSIONS: In general, the kinetics of wetlands act to slow down the flow of water whether surface or subsurface flow, which supports a full suite of wetland functions including temporary