> For the complete documentation index, see [llms.txt](https://swatplus.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://swatplus.gitbook.io/docs/master.md).

# About SWAT+

Over the past 20 years, the [Soil and Water Assessment Tool (SWAT)](https://swat.tamu.edu/) has become widely used across the globe. The large numbers of applications across the globe have also revealed limitations and identified model development needs. Numerous additions and modifications of the model and its individual components have made the code increasingly difficult to manage and maintain. In order to face present and future challenges in water resources modeling SWAT code has undergone major modifications over the past few years, resulting in SWAT+, a completely revised version of the model.

Even though the basic algorithms used to calculate the processes in the model have not changed, the structure and organization of both the code (object based) and the input files (relational based) have undergone considerable modification. This is expected to facilitate model maintenance, future code modifications, and foster collaboration with other researchers to integrate new science into SWAT modules. SWAT+ provides a more flexible spatial representation of interactions and processes within a watershed.

{% hint style="info" %}
The Soil and Water Assessment Tool Plus (SWAT+) is a public domain model jointly developed by the USDA Agricultural Research Service (USDA-ARS) and Texas A\&M AgriLife Research, part of The Texas A\&M University System. SWAT+ is a small watershed to river basin-scale model to simulate the quality and quantity of surface and ground water and predict the environmental impact of land use, land management practices, and climate change. SWAT is widely used in assessing soil erosion prevention and control, non-point source pollution control and regional management in watersheds.
{% endhint %}


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