The Worldwide Use of the SWAT Model: Technological Drivers, Networking Impacts, and Simulation Trends

Abstract

The Soil and Water Assessment Tool (SWAT) is one of the most widely used watershed-scale water quality models in the world. Nearly 600 peer-reviewed SWAT-related journal articles have been published and hundreds more have been published in conference proceedings and other formats. The SWAT model has proven to be a very flexible tool for investigating a range of hydrologic and water quality problems at different watershed scales, as well as very adaptable for applications requiring improved hydrologic and other enhanced simulation needs. We investigate here the various technological, networking, and other factors that have supported expanded use of SWAT, and also highlight current worldwide simulation trends. Examples of technological advances include easy access to web-based documentation, user-support groups, and SWAT literature, a variety of Geographic Information System (GIS) interface tools, pre- and post-processing calibration, statistical evaluation, and other software, and an open source code which has proven to be a model development catalyst for multiple user groups. Extensive networking regarding the use of SWAT has also developed, via internet-based user support groups, model training workshops, regional working groups, regional and international conferences, and targeted development workshops. The use of SWAT has expanded dramatically, not only in North America and Europe but also in Africa, Southeast Asia and countries such as China, India, and Iran. Several important trends have also emerged regarding improved hydrologic, best management practice (BMP), and pollutant transport methods, which will be further highlighted.