GSFLOW–GRASS v1.0.0: GIS-enabled hydrologic modeling of coupled groundwater–surface-water systems

Abstract

Abstract. The importance of water moving between the atmosphere and aquifers has led to efforts to develop and maintain coupled models of surface water and groundwater. However, developing inputs to these models is usually time-consuming and requires extensive knowledge of software engineering, often prohibiting their use by many researchers and water managers, thus reducing these models' potential to promote science-driven decision-making in an era of global change and increasing water resource stress. In response to this need, we have developed GSFLOW–GRASS, a bundled set of open-source tools that develops inputs for, executes, and graphically displays the results of GSFLOW, the U.S. Geological Survey's coupled groundwater and surface-water flow model. In order to create a robust tool that can be widely implemented over diverse hydro(geo)logic settings, we built a series of GRASS GIS extensions that automatically discretizes a topological surface-water flow network that is linked with an underlying gridded groundwater domain. As inputs, GSFLOW–GRASS requires at a minimum a digital elevation model, a precipitation and temperature record, and estimates of channel parameters and hydraulic conductivity. We demonstrate the broad applicability of the toolbox by successfully testing it in environments with varying degrees of drainage integration, landscape relief, and grid resolution, as well as the presence of irregular coastal boundaries. These examples also show how GSFLOW–GRASS can be implemented to examine the role of groundwater–surface-water interactions in a diverse range of water resource and land management applications.

Computing water flow through complex landscapes – Part 1: Incorporating depressions in flow routing using FlowFill

“…Flow-routing algorithms are applied across a broad range of fields, including hydrologic and geomorphic modelling, topographic analysis, planetary science, and palaeoclimate. They are a critical component of both hydrologic (Neal et al, 2011;Ng et al, 2018;Ray et al, 2016) and geomorphic (Adams et al, 2017;Coulthard et al, 2013) models, with the former including watershed-scale processes and flood risk. In the latter case, flow routing is often recomputed over time to simulate the feedback between evolving topography and drainage patterns (Hobley et al, 2017;Tucker et al, 2011).…”

“…In the latter case, flow routing is often recomputed over time to simulate the feedback between evolving topography and drainage patterns (Hobley et al, 2017;Tucker et al, 2011). Flow-routing calculations and drainage network construction also form the basis for topographic analysis algorithms to automatically pick channel heads (Clubb et al, 2014;Passalacqua et al, 2010;Pelletier, 2013), segment watersheds into representative hydrological units (Czuba and Foufoula-Georgiou, 2014;Ng et al, 2018;Teng et al, 2017), and link river-channel form with rates of tectonic uplift (Duvall et al, 2004;Perron and Royden, 2013;Willgoose et al, 1991) or subsidence (Paola et al, 1992;Wickert and Schildgen, 2019). These same tools have been applied to understand valley networks on Mars (Luo and Stepinski, 2009;Molloy and Stepinski, 2007), the impacts of freshwater forcing on climate during the most recent deglaciation (Ivanovic et al, 2017(Ivanovic et al, , 2018Riddick et al, 2018), and links between palaeo-drainage networks and modern economic and agri-cultural resources (Craddock et al, 2010).…”

“…Chu et al, 2013) and small catchments (e.g. Ng et al, 2018;Teng et al, 2017) to continents (e.g. Coe, 2000;Riddick et al, 2018;Wickert, 2016).…”

“…This step often results in the removal of all depressions from the original DEM (e.g. Jenson and Domingue, 1988;Garbrecht, 1998, 1999;O'Callaghan and Mark, 1984;Soille, 2004;Cordonnier et al, 2018). Removing depressions produces a topographic surface over which a flow-routing calculation will produce a fully connected hydrologic network.…”

Overview of software for analysis and visualization of hydrological data

“…Сучасні дослідження та розвиток ГІС інструментарію для розв'язання гідрологічних задач можна побачити в роботах [7][8][9][10][11][12][13][14][15][16][17].…”